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@a1d3s a1d3s commented Jun 5, 2015

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@jwrdegoede jwrdegoede force-pushed the sunxi-wip branch 7 times, most recently from b3679ff to ee140d3 Compare June 10, 2015 14:44
@a1d3s a1d3s closed this Jun 11, 2015
jwrdegoede pushed a commit that referenced this pull request Jul 28, 2015
	Normally opening a file, unlinking it and then closing will have
the inode freed upon close() (provided that it's not otherwise busy and
has no remaining links, of course).  However, there's one case where that
does *not* happen.  Namely, if you open it by fhandle with cold dcache,
then unlink() and close().

	In normal case you get d_delete() in unlink(2) notice that dentry
is busy and unhash it; on the final dput() it will be forcibly evicted from
dcache, triggering iput() and inode removal.  In this case, though, we end
up with *two* dentries - disconnected (created by open-by-fhandle) and
regular one (used by unlink()).  The latter will have its reference to inode
dropped just fine, but the former will not - it's considered hashed (it
is on the ->s_anon list), so it will stay around until the memory pressure
will finally do it in.  As the result, we have the final iput() delayed
indefinitely.  It's trivial to reproduce -

void flush_dcache(void)
{
        system("mount -o remount,rw /");
}

static char buf[20 * 1024 * 1024];

main()
{
        int fd;
        union {
                struct file_handle f;
                char buf[MAX_HANDLE_SZ];
        } x;
        int m;

        x.f.handle_bytes = sizeof(x);
        chdir("/root");
        mkdir("foo", 0700);
        fd = open("foo/bar", O_CREAT | O_RDWR, 0600);
        close(fd);
        name_to_handle_at(AT_FDCWD, "foo/bar", &x.f, &m, 0);
        flush_dcache();
        fd = open_by_handle_at(AT_FDCWD, &x.f, O_RDWR);
        unlink("foo/bar");
        write(fd, buf, sizeof(buf));
        system("df .");			/* 20Mb eaten */
        close(fd);
        system("df .");			/* should've freed those 20Mb */
        flush_dcache();
        system("df .");			/* should be the same as #2 */
}

will spit out something like
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 303843      1131 100% /
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 303843      1131 100% /
Filesystem     1K-blocks   Used Available Use% Mounted on
/dev/root         322023 283282     21692  93% /
- inode gets freed only when dentry is finally evicted (here we trigger
than by remount; normally it would've happened in response to memory
pressure hell knows when).

Cc: [email protected] # v2.6.38+; earlier ones need s/kill_it/unhash_it/
Acked-by: J. Bruce Fields <[email protected]>
Signed-off-by: Al Viro <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 31, 2015
[   68.196974] WARNING: CPU: 1 PID: 2140 at arch/x86/kvm/x86.c:3161 kvm_arch_vcpu_ioctl+0xe88/0x1340 [kvm]()
[   68.196975] Modules linked in: snd_hda_codec_hdmi i915 rfcomm bnep bluetooth i2c_algo_bit rfkill nfsd drm_kms_helper nfs_acl nfs drm lockd grace sunrpc fscache snd_hda_codec_realtek snd_hda_codec_generic snd_hda_intel snd_hda_codec snd_hda_core snd_hwdep snd_pcm snd_seq_dummy snd_seq_oss x86_pkg_temp_thermal snd_seq_midi kvm_intel snd_seq_midi_event snd_rawmidi kvm snd_seq ghash_clmulni_intel fuse snd_timer aesni_intel parport_pc ablk_helper snd_seq_device cryptd ppdev snd lp parport lrw dcdbas gf128mul i2c_core glue_helper lpc_ich video shpchp mfd_core soundcore serio_raw acpi_cpufreq ext4 mbcache jbd2 sd_mod crc32c_intel ahci libahci libata e1000e ptp pps_core
[   68.197005] CPU: 1 PID: 2140 Comm: qemu-system-x86 Not tainted 4.2.0-rc1+ #2
[   68.197006] Hardware name: Dell Inc. OptiPlex 7020/0F5C5X, BIOS A03 01/08/2015
[   68.197007]  ffffffffa03b0657 ffff8800d984bca8 ffffffff815915a2 0000000000000000
[   68.197009]  0000000000000000 ffff8800d984bce8 ffffffff81057c0a 00007ff6d0001000
[   68.197010]  0000000000000002 ffff880211c1a000 0000000000000004 ffff8800ce0288c0
[   68.197012] Call Trace:
[   68.197017]  [<ffffffff815915a2>] dump_stack+0x45/0x57
[   68.197020]  [<ffffffff81057c0a>] warn_slowpath_common+0x8a/0xc0
[   68.197022]  [<ffffffff81057cfa>] warn_slowpath_null+0x1a/0x20
[   68.197029]  [<ffffffffa037bed8>] kvm_arch_vcpu_ioctl+0xe88/0x1340 [kvm]
[   68.197035]  [<ffffffffa037aede>] ? kvm_arch_vcpu_load+0x4e/0x1c0 [kvm]
[   68.197040]  [<ffffffffa03696a6>] kvm_vcpu_ioctl+0xc6/0x5c0 [kvm]
[   68.197043]  [<ffffffff811252d2>] ? perf_pmu_enable+0x22/0x30
[   68.197044]  [<ffffffff8112663e>] ? perf_event_context_sched_in+0x7e/0xb0
[   68.197048]  [<ffffffff811a6882>] do_vfs_ioctl+0x2c2/0x4a0
[   68.197050]  [<ffffffff8107bf33>] ? finish_task_switch+0x173/0x220
[   68.197053]  [<ffffffff8123307f>] ? selinux_file_ioctl+0x4f/0xd0
[   68.197055]  [<ffffffff8122cac3>] ? security_file_ioctl+0x43/0x60
[   68.197057]  [<ffffffff811a6ad9>] SyS_ioctl+0x79/0x90
[   68.197060]  [<ffffffff81597e57>] entry_SYSCALL_64_fastpath+0x12/0x6a
[   68.197061] ---[ end trace 558a5ebf9445fc80 ]---

After commit (0c4109b 'x86/fpu/xstate: Fix up bad get_xsave_addr()
assumptions'), there is no assumption an xsave bit is present in the
hardware (pcntxt_mask) that it is always present in a given xsave buffer.
An enabled state to be present on 'pcntxt_mask', but *not* in 'xstate_bv'
could happen when the last 'xsave' did not request that this feature be
saved (unlikely) or because the "init optimization" caused it to not be
saved. This patch kill the assumption.

Signed-off-by: Wanpeng Li <[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 31, 2015
Using the clone ioctl (or extent_same ioctl, which calls the same extent
cloning function as well) we end up allowing copy an inline extent from
the source file into a non-zero offset of the destination file. This is
something not expected and that the btrfs code is not prepared to deal
with - all inline extents must be at a file offset equals to 0.

For example, the following excerpt of a test case for fstests triggers
a crash/BUG_ON() on a write operation after an inline extent is cloned
into a non-zero offset:

  _scratch_mkfs >>$seqres.full 2>&1
  _scratch_mount

  # Create our test files. File foo has the same 2K of data at offset 4K
  # as file bar has at its offset 0.
  $XFS_IO_PROG -f -s -c "pwrite -S 0xaa 0 4K" \
      -c "pwrite -S 0xbb 4k 2K" \
      -c "pwrite -S 0xcc 8K 4K" \
      $SCRATCH_MNT/foo | _filter_xfs_io

  # File bar consists of a single inline extent (2K size).
  $XFS_IO_PROG -f -s -c "pwrite -S 0xbb 0 2K" \
     $SCRATCH_MNT/bar | _filter_xfs_io

  # Now call the clone ioctl to clone the extent of file bar into file
  # foo at its offset 4K. This made file foo have an inline extent at
  # offset 4K, something which the btrfs code can not deal with in future
  # IO operations because all inline extents are supposed to start at an
  # offset of 0, resulting in all sorts of chaos.
  # So here we validate that clone ioctl returns an EOPNOTSUPP, which is
  # what it returns for other cases dealing with inlined extents.
  $CLONER_PROG -s 0 -d $((4 * 1024)) -l $((2 * 1024)) \
      $SCRATCH_MNT/bar $SCRATCH_MNT/foo

  # Because of the inline extent at offset 4K, the following write made
  # the kernel crash with a BUG_ON().
  $XFS_IO_PROG -c "pwrite -S 0xdd 6K 2K" $SCRATCH_MNT/foo | _filter_xfs_io

  status=0
  exit

The stack trace of the BUG_ON() triggered by the last write is:

  [152154.035903] ------------[ cut here ]------------
  [152154.036424] kernel BUG at mm/page-writeback.c:2286!
  [152154.036424] invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
  [152154.036424] Modules linked in: btrfs dm_flakey dm_mod crc32c_generic xor raid6_pq nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc loop fuse parport_pc acpi_cpu$
  [152154.036424] CPU: 2 PID: 17873 Comm: xfs_io Tainted: G        W       4.1.0-rc6-btrfs-next-11+ #2
  [152154.036424] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.8.1-0-g4adadbd-20150316_085822-nilsson.home.kraxel.org 04/01/2014
  [152154.036424] task: ffff880429f70990 ti: ffff880429efc000 task.ti: ffff880429efc000
  [152154.036424] RIP: 0010:[<ffffffff8111a9d5>]  [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
  [152154.036424] RSP: 0018:ffff880429effc68  EFLAGS: 00010246
  [152154.036424] RAX: 0200000000000806 RBX: ffffea0006a6d8f0 RCX: 0000000000000001
  [152154.036424] RDX: 0000000000000000 RSI: ffffffff81155d1b RDI: ffffea0006a6d8f0
  [152154.036424] RBP: ffff880429effc78 R08: ffff8801ce389fe0 R09: 0000000000000001
  [152154.036424] R10: 0000000000002000 R11: ffffffffffffffff R12: ffff8800200dce68
  [152154.036424] R13: 0000000000000000 R14: ffff8800200dcc88 R15: ffff8803d5736d80
  [152154.036424] FS:  00007fbf119f6700(0000) GS:ffff88043d280000(0000) knlGS:0000000000000000
  [152154.036424] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [152154.036424] CR2: 0000000001bdc000 CR3: 00000003aa555000 CR4: 00000000000006e0
  [152154.036424] Stack:
  [152154.036424]  ffff8803d5736d80 0000000000000001 ffff880429effcd8 ffffffffa04e97c1
  [152154.036424]  ffff880429effd68 ffff880429effd60 0000000000000001 ffff8800200dc9c8
  [152154.036424]  0000000000000001 ffff8800200dcc88 0000000000000000 0000000000001000
  [152154.036424] Call Trace:
  [152154.036424]  [<ffffffffa04e97c1>] lock_and_cleanup_extent_if_need+0x147/0x18d [btrfs]
  [152154.036424]  [<ffffffffa04ea82c>] __btrfs_buffered_write+0x245/0x4c8 [btrfs]
  [152154.036424]  [<ffffffffa04ed14b>] ? btrfs_file_write_iter+0x150/0x3e0 [btrfs]
  [152154.036424]  [<ffffffffa04ed15a>] ? btrfs_file_write_iter+0x15f/0x3e0 [btrfs]
  [152154.036424]  [<ffffffffa04ed2c7>] btrfs_file_write_iter+0x2cc/0x3e0 [btrfs]
  [152154.036424]  [<ffffffff81165a4a>] __vfs_write+0x7c/0xa5
  [152154.036424]  [<ffffffff81165f89>] vfs_write+0xa0/0xe4
  [152154.036424]  [<ffffffff81166855>] SyS_pwrite64+0x64/0x82
  [152154.036424]  [<ffffffff81465197>] system_call_fastpath+0x12/0x6f
  [152154.036424] Code: 48 89 c7 e8 0f ff ff ff 5b 41 5c 5d c3 0f 1f 44 00 00 55 48 89 e5 41 54 53 48 89 fb e8 ae ef 00 00 49 89 c4 48 8b 03 a8 01 75 02 <0f> 0b 4d 85 e4 74 59 49 8b 3c 2$
  [152154.036424] RIP  [<ffffffff8111a9d5>] clear_page_dirty_for_io+0x1e/0x90
  [152154.036424]  RSP <ffff880429effc68>
  [152154.242621] ---[ end trace e3d3376b23a57041 ]---

Fix this by returning the error EOPNOTSUPP if an attempt to copy an
inline extent into a non-zero offset happens, just like what is done for
other scenarios that would require copying/splitting inline extents,
which were introduced by the following commits:

   00fdf13 ("Btrfs: fix a crash of clone with inline extents's split")
   3f9e3df ("btrfs: replace error code from btrfs_drop_extents")

Cc: [email protected]
Signed-off-by: Filipe Manana <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 31, 2015
__ipoib_ib_dev_flush calls itself recursively on child devices, and lockdep
complains about locking vlan_rwsem twice (see below). Use down_read_nested
instead of down_read to prevent the warning.

 =============================================
 [ INFO: possible recursive locking detected ]
 4.1.0-rc4+ linux-sunxi#36 Tainted: G           O
 ---------------------------------------------
 kworker/u20:2/261 is trying to acquire lock:
  (&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]

 but task is already holding lock:
  (&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&priv->vlan_rwsem);
   lock(&priv->vlan_rwsem);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 3 locks held by kworker/u20:2/261:
  #0:  ("%s""ipoib_flush"){.+.+..}, at: [<ffffffff810827cc>] process_one_work+0x15c/0x760
  #1:  ((&priv->flush_heavy)){+.+...}, at: [<ffffffff810827cc>] process_one_work+0x15c/0x760
  #2:  (&priv->vlan_rwsem){.+.+..}, at: [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]

 stack backtrace:
 CPU: 3 PID: 261 Comm: kworker/u20:2 Tainted: G           O    4.1.0-rc4+ linux-sunxi#36
 Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2007
 Workqueue: ipoib_flush ipoib_ib_dev_flush_heavy [ib_ipoib]
  ffff8801c6c54790 ffff8801c9927af8 ffffffff81665238 0000000000000001
  ffffffff825b5b30 ffff8801c9927bd8 ffffffff810bba51 ffff880100000000
  ffffffff00000001 ffff880100000001 ffff8801c6c55428 ffff8801c6c54790
 Call Trace:
  [<ffffffff81665238>] dump_stack+0x4f/0x6f
  [<ffffffff810bba51>] __lock_acquire+0x741/0x1820
  [<ffffffff810bcbf8>] lock_acquire+0xc8/0x240
  [<ffffffffa0791e2a>] ? __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
  [<ffffffff81669d2c>] down_read+0x4c/0x70
  [<ffffffffa0791e2a>] ? __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
  [<ffffffffa0791e2a>] __ipoib_ib_dev_flush+0x3a/0x2b0 [ib_ipoib]
  [<ffffffffa0791e4a>] __ipoib_ib_dev_flush+0x5a/0x2b0 [ib_ipoib]
  [<ffffffffa07920ba>] ipoib_ib_dev_flush_heavy+0x1a/0x20 [ib_ipoib]
  [<ffffffff81082871>] process_one_work+0x201/0x760
  [<ffffffff810827cc>] ? process_one_work+0x15c/0x760
  [<ffffffff81082ef0>] worker_thread+0x120/0x4d0
  [<ffffffff81082dd0>] ? process_one_work+0x760/0x760
  [<ffffffff81082dd0>] ? process_one_work+0x760/0x760
  [<ffffffff81088b7e>] kthread+0xfe/0x120
  [<ffffffff81088a80>] ? __init_kthread_worker+0x70/0x70
  [<ffffffff8166c6e2>] ret_from_fork+0x42/0x70
  [<ffffffff81088a80>] ? __init_kthread_worker+0x70/0x70

Signed-off-by: Haggai Eran <[email protected]>
Signed-off-by: Doug Ledford <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 31, 2015
Kirill A. Shutemov says:

This simple test-case trigers few locking asserts in kernel:

int main(int argc, char **argv)
{
        unsigned int block_size = 16 * 4096;
        struct nl_mmap_req req = {
                .nm_block_size          = block_size,
                .nm_block_nr            = 64,
                .nm_frame_size          = 16384,
                .nm_frame_nr            = 64 * block_size / 16384,
        };
        unsigned int ring_size;
	int fd;

	fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
        if (setsockopt(fd, SOL_NETLINK, NETLINK_RX_RING, &req, sizeof(req)) < 0)
                exit(1);
        if (setsockopt(fd, SOL_NETLINK, NETLINK_TX_RING, &req, sizeof(req)) < 0)
                exit(1);

	ring_size = req.nm_block_nr * req.nm_block_size;
	mmap(NULL, 2 * ring_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
	return 0;
}

+++ exited with 0 +++
BUG: sleeping function called from invalid context at /home/kas/git/public/linux-mm/kernel/locking/mutex.c:616
in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: init
3 locks held by init/1:
 #0:  (reboot_mutex){+.+...}, at: [<ffffffff81080959>] SyS_reboot+0xa9/0x220
 #1:  ((reboot_notifier_list).rwsem){.+.+..}, at: [<ffffffff8107f379>] __blocking_notifier_call_chain+0x39/0x70
 #2:  (rcu_callback){......}, at: [<ffffffff810d32e0>] rcu_do_batch.isra.49+0x160/0x10c0
Preemption disabled at:[<ffffffff8145365f>] __delay+0xf/0x20

CPU: 1 PID: 1 Comm: init Not tainted 4.1.0-00009-gbddf4c4818e0 linux-sunxi#253
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Debian-1.8.2-1 04/01/2014
 ffff88017b3d8000 ffff88027bc03c38 ffffffff81929ceb 0000000000000102
 0000000000000000 ffff88027bc03c68 ffffffff81085a9d 0000000000000002
 ffffffff81ca2a20 0000000000000268 0000000000000000 ffff88027bc03c98
Call Trace:
 <IRQ>  [<ffffffff81929ceb>] dump_stack+0x4f/0x7b
 [<ffffffff81085a9d>] ___might_sleep+0x16d/0x270
 [<ffffffff81085bed>] __might_sleep+0x4d/0x90
 [<ffffffff8192e96f>] mutex_lock_nested+0x2f/0x430
 [<ffffffff81932fed>] ? _raw_spin_unlock_irqrestore+0x5d/0x80
 [<ffffffff81464143>] ? __this_cpu_preempt_check+0x13/0x20
 [<ffffffff8182fc3d>] netlink_set_ring+0x1ed/0x350
 [<ffffffff8182e000>] ? netlink_undo_bind+0x70/0x70
 [<ffffffff8182fe20>] netlink_sock_destruct+0x80/0x150
 [<ffffffff817e484d>] __sk_free+0x1d/0x160
 [<ffffffff817e49a9>] sk_free+0x19/0x20
[..]

Cong Wang says:

We can't hold mutex lock in a rcu callback, [..]

Thomas Graf says:

The socket should be dead at this point. It might be simpler to
add a netlink_release_ring() function which doesn't require
locking at all.

Reported-by: "Kirill A. Shutemov" <[email protected]>
Diagnosed-by: Cong Wang <[email protected]>
Suggested-by: Thomas Graf <[email protected]>
Signed-off-by: Florian Westphal <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 14, 2015
The probe error path for this driver, for all intents and purposes,
is the talitos_remove() function due to the common "goto err_out".

Without this patch applied, talitos_remove() will panic under these
two conditions:

1. If the RNG device hasn't been registered via
   talitos_register_rng() prior to entry into talitos_remove(),
   then the attempt to unregister the RNG "device" will cause a panic.

2. If the priv->chan array has not been allocated prior to entry
   into talitos_remove(), then the per-channel FIFO cleanup will panic
   because of the dereference of that NULL "array".

Both of the above scenarios occur if talitos_probe_irq() fails.

This patch resolves issue #1 by introducing a boolean to mask the
hwrng_unregister() call in talitos_unregister_rng() if RNG device
registration was unsuccessful.

It resolves issue #2 by checking that priv->chan is not NULL in the
per-channel FIFO cleanup for loop.

Signed-off-by: Aaron Sierra <[email protected]>
Signed-off-by: Herbert Xu <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
In dev_queue_xmit() net_cls protected with rcu-bh.

[  270.730026] ===============================
[  270.730029] [ INFO: suspicious RCU usage. ]
[  270.730033] 4.2.0-rc3+ #2 Not tainted
[  270.730036] -------------------------------
[  270.730040] include/linux/cgroup.h:353 suspicious rcu_dereference_check() usage!
[  270.730041] other info that might help us debug this:
[  270.730043] rcu_scheduler_active = 1, debug_locks = 1
[  270.730045] 2 locks held by dhclient/748:
[  270.730046]  #0:  (rcu_read_lock_bh){......}, at: [<ffffffff81682b70>] __dev_queue_xmit+0x50/0x960
[  270.730085]  #1:  (&qdisc_tx_lock){+.....}, at: [<ffffffff81682d60>] __dev_queue_xmit+0x240/0x960
[  270.730090] stack backtrace:
[  270.730096] CPU: 0 PID: 748 Comm: dhclient Not tainted 4.2.0-rc3+ #2
[  270.730098] Hardware name: OpenStack Foundation OpenStack Nova, BIOS Bochs 01/01/2011
[  270.730100]  0000000000000001 ffff8800bafeba58 ffffffff817ad487 0000000000000007
[  270.730103]  ffff880232a0a780 ffff8800bafeba88 ffffffff810ca4f2 ffff88022fb23e00
[  270.730105]  ffff880232a0a780 ffff8800bafebb68 ffff8800bafebb68 ffff8800bafebaa8
[  270.730108] Call Trace:
[  270.730121]  [<ffffffff817ad487>] dump_stack+0x4c/0x65
[  270.730148]  [<ffffffff810ca4f2>] lockdep_rcu_suspicious+0xe2/0x120
[  270.730153]  [<ffffffff816a62d2>] task_cls_state+0x92/0xa0
[  270.730158]  [<ffffffffa00b534f>] cls_cgroup_classify+0x4f/0x120 [cls_cgroup]
[  270.730164]  [<ffffffff816aac74>] tc_classify_compat+0x74/0xc0
[  270.730166]  [<ffffffff816ab573>] tc_classify+0x33/0x90
[  270.730170]  [<ffffffffa00bcb0a>] htb_enqueue+0xaa/0x4a0 [sch_htb]
[  270.730172]  [<ffffffff81682e26>] __dev_queue_xmit+0x306/0x960
[  270.730174]  [<ffffffff81682b70>] ? __dev_queue_xmit+0x50/0x960
[  270.730176]  [<ffffffff816834a3>] dev_queue_xmit_sk+0x13/0x20
[  270.730185]  [<ffffffff81787770>] dev_queue_xmit+0x10/0x20
[  270.730187]  [<ffffffff8178b91c>] packet_snd.isra.62+0x54c/0x760
[  270.730190]  [<ffffffff8178be25>] packet_sendmsg+0x2f5/0x3f0
[  270.730203]  [<ffffffff81665245>] ? sock_def_readable+0x5/0x190
[  270.730210]  [<ffffffff817b64bb>] ? _raw_spin_unlock+0x2b/0x40
[  270.730216]  [<ffffffff8173bcbc>] ? unix_dgram_sendmsg+0x5cc/0x640
[  270.730219]  [<ffffffff8165f367>] sock_sendmsg+0x47/0x50
[  270.730221]  [<ffffffff8165f42f>] sock_write_iter+0x7f/0xd0
[  270.730232]  [<ffffffff811fd4c7>] __vfs_write+0xa7/0xf0
[  270.730234]  [<ffffffff811fe5b8>] vfs_write+0xb8/0x190
[  270.730236]  [<ffffffff811fe8c2>] SyS_write+0x52/0xb0
[  270.730239]  [<ffffffff817b6bae>] entry_SYSCALL_64_fastpath+0x12/0x76

Signed-off-by: Konstantin Khlebnikov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
The cgroup attaches inode->i_wb via mark_inode_dirty and when set_page_writeback
is called, __inc_wb_stat() updates i_wb's stat.

So, we need to explicitly call set_page_dirty->__mark_inode_dirty in prior to
any writebacking pages.

This patch should resolve the following kernel panic reported by Andreas Reis.

https://bugzilla.kernel.org/show_bug.cgi?id=101801

--- Comment #2 from Andreas Reis <[email protected]> ---
BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
IP: [<ffffffff8149deea>] __percpu_counter_add+0x1a/0x90
PGD 2951ff067 PUD 2df43f067 PMD 0
Oops: 0000 [#1] PREEMPT SMP
Modules linked in:
CPU: 7 PID: 10356 Comm: gcc Tainted: G        W       4.2.0-1-cu #1
Hardware name: Gigabyte Technology Co., Ltd. G1.Sniper M5/G1.Sniper M5, BIOS
T01 02/03/2015
task: ffff880295044f80 ti: ffff880295140000 task.ti: ffff880295140000
RIP: 0010:[<ffffffff8149deea>]  [<ffffffff8149deea>]
__percpu_counter_add+0x1a/0x90
RSP: 0018:ffff880295143ac8  EFLAGS: 00010082
RAX: 0000000000000003 RBX: ffffea000a526d40 RCX: 0000000000000001
RDX: 0000000000000020 RSI: 0000000000000001 RDI: 0000000000000088
RBP: ffff880295143ae8 R08: 0000000000000000 R09: ffff88008f69bb30
R10: 00000000fffffffa R11: 0000000000000000 R12: 0000000000000088
R13: 0000000000000001 R14: ffff88041d099000 R15: ffff880084a205d0
FS:  00007f8549374700(0000) GS:ffff88042f3c0000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000000a8 CR3: 000000033e1d5000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 0000000000000000 ffffea000a526d40 ffff880084a20738 ffff880084a20750
 ffff880295143b48 ffffffff811cc91e ffff880000000000 0000000000000296
 0000000000000000 ffff880417090198 0000000000000000 ffffea000a526d40
Call Trace:
 [<ffffffff811cc91e>] __test_set_page_writeback+0xde/0x1d0
 [<ffffffff813fee87>] do_write_data_page+0xe7/0x3a0
 [<ffffffff813faeea>] gc_data_segment+0x5aa/0x640
 [<ffffffff813fb0b8>] do_garbage_collect+0x138/0x150
 [<ffffffff813fb3fe>] f2fs_gc+0x1be/0x3e0
 [<ffffffff81405541>] f2fs_balance_fs+0x81/0x90
 [<ffffffff813ee357>] f2fs_unlink+0x47/0x1d0
 [<ffffffff81239329>] vfs_unlink+0x109/0x1b0
 [<ffffffff8123e3d7>] do_unlinkat+0x287/0x2c0
 [<ffffffff8123ebc6>] SyS_unlink+0x16/0x20
 [<ffffffff81942e2e>] entry_SYSCALL_64_fastpath+0x12/0x71
Code: 41 5e 5d c3 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 89 e5 41 55 49
89 f5 41 54 49 89 fc 53 48 83 ec 08 65 ff 05 e6 d9 b6 7e <48> 8b 47 20 48 63 ca
65 8b 18 48 63 db 48 01 f3 48 39 cb 7d 0a
RIP  [<ffffffff8149deea>] __percpu_counter_add+0x1a/0x90
 RSP <ffff880295143ac8>
CR2: 00000000000000a8
---[ end trace 5132449a58ed93a3 ]---
note: gcc[10356] exited with preempt_count 2

Signed-off-by: Jaegeuk Kim <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
Hayes Wang says:

====================
r8152: issues fix

v2:
Replace patch #2 with "r8152: fix wakeup settings".

v1:
These patches are used to fix issues.
====================

Signed-off-by: David S. Miller <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
Hayes Wang says:

====================
r8152: device reset

v3:
For patch #2, remove cancel_delayed_work().

v2:
For patch #1, remove usb_autopm_get_interface(), usb_autopm_put_interface(), and
the checking of intf->condition.

For patch #2, replace the original method with usb_queue_reset_device() to reset
the device.

v1:
Although the driver works normally, we find the device may get all 0xff data when
transmitting packets on certain platforms. It would break the device and no packet
could be transmitted. The reset is necessary to recover the hw for this situation.
====================

Signed-off-by: David S. Miller <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
Nikolay has reported a hang when a memcg reclaim got stuck with the
following backtrace:

PID: 18308  TASK: ffff883d7c9b0a30  CPU: 1   COMMAND: "rsync"
  #0 __schedule at ffffffff815ab152
  #1 schedule at ffffffff815ab76e
  #2 schedule_timeout at ffffffff815ae5e5
  #3 io_schedule_timeout at ffffffff815aad6a
  #4 bit_wait_io at ffffffff815abfc6
  #5 __wait_on_bit at ffffffff815abda5
  #6 wait_on_page_bit at ffffffff8111fd4f
  #7 shrink_page_list at ffffffff81135445
  #8 shrink_inactive_list at ffffffff81135845
  #9 shrink_lruvec at ffffffff81135ead
 #10 shrink_zone at ffffffff811360c3
 #11 shrink_zones at ffffffff81136eff
 #12 do_try_to_free_pages at ffffffff8113712f
 linux-sunxi#13 try_to_free_mem_cgroup_pages at ffffffff811372be
 linux-sunxi#14 try_charge at ffffffff81189423
 linux-sunxi#15 mem_cgroup_try_charge at ffffffff8118c6f5
 linux-sunxi#16 __add_to_page_cache_locked at ffffffff8112137d
 linux-sunxi#17 add_to_page_cache_lru at ffffffff81121618
 linux-sunxi#18 pagecache_get_page at ffffffff8112170b
 linux-sunxi#19 grow_dev_page at ffffffff811c8297
 linux-sunxi#20 __getblk_slow at ffffffff811c91d6
 linux-sunxi#21 __getblk_gfp at ffffffff811c92c1
 linux-sunxi#22 ext4_ext_grow_indepth at ffffffff8124565c
 linux-sunxi#23 ext4_ext_create_new_leaf at ffffffff81246ca8
 linux-sunxi#24 ext4_ext_insert_extent at ffffffff81246f09
 linux-sunxi#25 ext4_ext_map_blocks at ffffffff8124a848
 linux-sunxi#26 ext4_map_blocks at ffffffff8121a5b7
 linux-sunxi#27 mpage_map_one_extent at ffffffff8121b1fa
 linux-sunxi#28 mpage_map_and_submit_extent at ffffffff8121f07b
 linux-sunxi#29 ext4_writepages at ffffffff8121f6d5
 linux-sunxi#30 do_writepages at ffffffff8112c490
 linux-sunxi#31 __filemap_fdatawrite_range at ffffffff81120199
 linux-sunxi#32 filemap_flush at ffffffff8112041c
 linux-sunxi#33 ext4_alloc_da_blocks at ffffffff81219da1
 linux-sunxi#34 ext4_rename at ffffffff81229b91
 linux-sunxi#35 ext4_rename2 at ffffffff81229e32
 linux-sunxi#36 vfs_rename at ffffffff811a08a5
 linux-sunxi#37 SYSC_renameat2 at ffffffff811a3ffc
 linux-sunxi#38 sys_renameat2 at ffffffff811a408e
 linux-sunxi#39 sys_rename at ffffffff8119e51e
 linux-sunxi#40 system_call_fastpath at ffffffff815afa89

Dave Chinner has properly pointed out that this is a deadlock in the
reclaim code because ext4 doesn't submit pages which are marked by
PG_writeback right away.

The heuristic was introduced by commit e62e384 ("memcg: prevent OOM
with too many dirty pages") and it was applied only when may_enter_fs
was specified.  The code has been changed by c3b94f4 ("memcg:
further prevent OOM with too many dirty pages") which has removed the
__GFP_FS restriction with a reasoning that we do not get into the fs
code.  But this is not sufficient apparently because the fs doesn't
necessarily submit pages marked PG_writeback for IO right away.

ext4_bio_write_page calls io_submit_add_bh but that doesn't necessarily
submit the bio.  Instead it tries to map more pages into the bio and
mpage_map_one_extent might trigger memcg charge which might end up
waiting on a page which is marked PG_writeback but hasn't been submitted
yet so we would end up waiting for something that never finishes.

Fix this issue by replacing __GFP_IO by may_enter_fs check (for case 2)
before we go to wait on the writeback.  The page fault path, which is
the only path that triggers memcg oom killer since 3.12, shouldn't
require GFP_NOFS and so we shouldn't reintroduce the premature OOM
killer issue which was originally addressed by the heuristic.

As per David Chinner the xfs is doing similar thing since 2.6.15 already
so ext4 is not the only affected filesystem.  Moreover he notes:

: For example: IO completion might require unwritten extent conversion
: which executes filesystem transactions and GFP_NOFS allocations. The
: writeback flag on the pages can not be cleared until unwritten
: extent conversion completes. Hence memory reclaim cannot wait on
: page writeback to complete in GFP_NOFS context because it is not
: safe to do so, memcg reclaim or otherwise.

Cc: [email protected] # 3.9+
[[email protected]: corrected the control flow]
Fixes: c3b94f4 ("memcg: further prevent OOM with too many dirty pages")
Reported-by: Nikolay Borisov <[email protected]>
Signed-off-by: Michal Hocko <[email protected]>
Signed-off-by: Hugh Dickins <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
The shm implementation internally uses shmem or hugetlbfs inodes for shm
segments.  As these inodes are never directly exposed to userspace and
only accessed through the shm operations which are already hooked by
security modules, mark the inodes with the S_PRIVATE flag so that inode
security initialization and permission checking is skipped.

This was motivated by the following lockdep warning:

  ======================================================
   [ INFO: possible circular locking dependency detected ]
   4.2.0-0.rc3.git0.1.fc24.x86_64+debug #1 Tainted: G        W
  -------------------------------------------------------
   httpd/1597 is trying to acquire lock:
   (&ids->rwsem){+++++.}, at: shm_close+0x34/0x130
   but task is already holding lock:
   (&mm->mmap_sem){++++++}, at: SyS_shmdt+0x4b/0x180
   which lock already depends on the new lock.
   the existing dependency chain (in reverse order) is:
   -> #3 (&mm->mmap_sem){++++++}:
        lock_acquire+0xc7/0x270
        __might_fault+0x7a/0xa0
        filldir+0x9e/0x130
        xfs_dir2_block_getdents.isra.12+0x198/0x1c0 [xfs]
        xfs_readdir+0x1b4/0x330 [xfs]
        xfs_file_readdir+0x2b/0x30 [xfs]
        iterate_dir+0x97/0x130
        SyS_getdents+0x91/0x120
        entry_SYSCALL_64_fastpath+0x12/0x76
   -> #2 (&xfs_dir_ilock_class){++++.+}:
        lock_acquire+0xc7/0x270
        down_read_nested+0x57/0xa0
        xfs_ilock+0x167/0x350 [xfs]
        xfs_ilock_attr_map_shared+0x38/0x50 [xfs]
        xfs_attr_get+0xbd/0x190 [xfs]
        xfs_xattr_get+0x3d/0x70 [xfs]
        generic_getxattr+0x4f/0x70
        inode_doinit_with_dentry+0x162/0x670
        sb_finish_set_opts+0xd9/0x230
        selinux_set_mnt_opts+0x35c/0x660
        superblock_doinit+0x77/0xf0
        delayed_superblock_init+0x10/0x20
        iterate_supers+0xb3/0x110
        selinux_complete_init+0x2f/0x40
        security_load_policy+0x103/0x600
        sel_write_load+0xc1/0x750
        __vfs_write+0x37/0x100
        vfs_write+0xa9/0x1a0
        SyS_write+0x58/0xd0
        entry_SYSCALL_64_fastpath+0x12/0x76
  ...

Signed-off-by: Stephen Smalley <[email protected]>
Reported-by: Morten Stevens <[email protected]>
Acked-by: Hugh Dickins <[email protected]>
Acked-by: Paul Moore <[email protected]>
Cc: Manfred Spraul <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Prarit Bhargava <[email protected]>
Cc: Eric Paris <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 23, 2015
It turns out that a PV domU also requires the "Xen PV" APIC
driver. Otherwise, the flat driver is used and we get stuck in busy
loops that never exit, such as in this stack trace:

(gdb) target remote localhost:9999
Remote debugging using localhost:9999
__xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
56              while (native_apic_mem_read(APIC_ICR) & APIC_ICR_BUSY)
(gdb) bt
 #0  __xapic_wait_icr_idle () at ./arch/x86/include/asm/ipi.h:56
 #1  __default_send_IPI_shortcut (shortcut=<optimized out>,
dest=<optimized out>, vector=<optimized out>) at
./arch/x86/include/asm/ipi.h:75
 #2  apic_send_IPI_self (vector=246) at arch/x86/kernel/apic/probe_64.c:54
 #3  0xffffffff81011336 in arch_irq_work_raise () at
arch/x86/kernel/irq_work.c:47
 #4  0xffffffff8114990c in irq_work_queue (work=0xffff88000fc0e400) at
kernel/irq_work.c:100
 #5  0xffffffff8110c29d in wake_up_klogd () at kernel/printk/printk.c:2633
 #6  0xffffffff8110ca60 in vprintk_emit (facility=0, level=<optimized
out>, dict=0x0 <irq_stack_union>, dictlen=<optimized out>,
fmt=<optimized out>, args=<optimized out>)
    at kernel/printk/printk.c:1778
 #7  0xffffffff816010c8 in printk (fmt=<optimized out>) at
kernel/printk/printk.c:1868
 #8  0xffffffffc00013ea in ?? ()
 #9  0x0000000000000000 in ?? ()

Mailing-list-thread: https://lkml.org/lkml/2015/8/4/755
Signed-off-by: Jason A. Donenfeld <[email protected]>
Cc: <[email protected]>
Signed-off-by: David Vrabel <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 29, 2015
Kernel testing triggered this warning:

| WARNING: CPU: 0 PID: 13 at kernel/sched/core.c:1156 do_set_cpus_allowed+0x7e/0x80()
| Modules linked in:
| CPU: 0 PID: 13 Comm: migration/0 Not tainted 4.2.0-rc1-00049-g25834c7 #2
| Call Trace:
|   dump_stack+0x4b/0x75
|   warn_slowpath_common+0x8b/0xc0
|   warn_slowpath_null+0x22/0x30
|   do_set_cpus_allowed+0x7e/0x80
|   cpuset_cpus_allowed_fallback+0x7c/0x170
|   select_fallback_rq+0x221/0x280
|   migration_call+0xe3/0x250
|   notifier_call_chain+0x53/0x70
|   __raw_notifier_call_chain+0x1e/0x30
|   cpu_notify+0x28/0x50
|   take_cpu_down+0x22/0x40
|   multi_cpu_stop+0xd5/0x140
|   cpu_stopper_thread+0xbc/0x170
|   smpboot_thread_fn+0x174/0x2f0
|   kthread+0xc4/0xe0
|   ret_from_kernel_thread+0x21/0x30

As Peterz pointed out:

| So the normal rules for changing task_struct::cpus_allowed are holding
| both pi_lock and rq->lock, such that holding either stabilizes the mask.
|
| This is so that wakeup can happen without rq->lock and load-balance
| without pi_lock.
|
| From this we already get the relaxation that we can omit acquiring
| rq->lock if the task is not on the rq, because in that case
| load-balancing will not apply to it.
|
| ** these are the rules currently tested in do_set_cpus_allowed() **
|
| Now, since __set_cpus_allowed_ptr() uses task_rq_lock() which
| unconditionally acquires both locks, we could get away with holding just
| rq->lock when on_rq for modification because that'd still exclude
| __set_cpus_allowed_ptr(), it would also work against
| __kthread_bind_mask() because that assumes !on_rq.
|
| That said, this is all somewhat fragile.
|
| Now, I don't think dropping rq->lock is quite as disastrous as it
| usually is because !cpu_active at this point, which means load-balance
| will not interfere, but that too is somewhat fragile.
|
| So we end up with a choice of two fragile..

This patch fixes it by following the rules for changing
task_struct::cpus_allowed with both pi_lock and rq->lock held.

Reported-by: kernel test robot <[email protected]>
Reported-by: Sasha Levin <[email protected]>
Signed-off-by: Wanpeng Li <[email protected]>
[ Modified changelog and patch. ]
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 29, 2015
The renesas-irqc interrupt controller is cascaded to the GIC. Hence when
propagating wake-up settings to its parent interrupt controller, the
following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-ape6evm-10725-g50fcd7643c034198 linux-sunxi#280 Not tainted
    ---------------------------------------------
    s2ram/1072 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    6 locks held by s2ram/1072:
    #0:  (sb_writers#7){.+.+.+}, at: [<c012eb14>] __sb_start_write+0xa0/0xa8
    #1:  (&of->mutex){+.+.+.}, at: [<c019396c>] kernfs_fop_write+0x4c/0x1bc
    #2:  (s_active#24){.+.+.+}, at: [<c0193974>] kernfs_fop_write+0x54/0x1bc
    #3:  (pm_mutex){+.+.+.}, at: [<c008213c>] pm_suspend+0x10c/0x510
    #4:  (&dev->mutex){......}, at: [<c02af3c4>] __device_suspend+0xdc/0x2cc
    #5:  (&irq_desc_lock_class){-.-...}, at: [<c008d3fc>] __irq_get_desc_lock+0x58/0x98

    stack backtrace:
    CPU: 0 PID: 1072 Comm: s2ram Not tainted 4.2.0-ape6evm-10725-g50fcd7643c034198 linux-sunxi#280
    Hardware name: Generic R8A73A4 (Flattened Device Tree)
    [<c0018078>] (unwind_backtrace) from [<c00144f0>] (show_stack+0x10/0x14)
    [<c00144f0>] (show_stack) from [<c0451f14>] (dump_stack+0x88/0x98)
    [<c0451f14>] (dump_stack) from [<c007b29c>] (__lock_acquire+0x15cc/0x20e4)
    [<c007b29c>] (__lock_acquire) from [<c007c6e0>] (lock_acquire+0xac/0x12c)
    [<c007c6e0>] (lock_acquire) from [<c0457c00>] (_raw_spin_lock_irqsave+0x40/0x54)
    [<c0457c00>] (_raw_spin_lock_irqsave) from [<c008d3fc>] (__irq_get_desc_lock+0x58/0x98)
    [<c008d3fc>] (__irq_get_desc_lock) from [<c008ebbc>] (irq_set_irq_wake+0x20/0xf8)
    [<c008ebbc>] (irq_set_irq_wake) from [<c0260770>] (irqc_irq_set_wake+0x20/0x4c)
    [<c0260770>] (irqc_irq_set_wake) from [<c008ec28>] (irq_set_irq_wake+0x8c/0xf8)
    [<c008ec28>] (irq_set_irq_wake) from [<c02cb8c0>] (gpio_keys_suspend+0x74/0xc0)
    [<c02cb8c0>] (gpio_keys_suspend) from [<c02ae8cc>] (dpm_run_callback+0x54/0x124)

Avoid this false positive by using a separate lockdep class for IRQC
interrupts.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Cc: Grygorii Strashko <[email protected]>
Cc: Magnus Damm <[email protected]>
Cc: Jason Cooper <[email protected]>
Link: http://lkml.kernel.org/r/1441798974-25716-2-git-send-email-geert%[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 29, 2015
The renesas-intc-irqpin interrupt controller is cascaded to the GIC.
Hence when propagating wake-up settings to its parent interrupt
controller, the following lockdep warning is printed:

    =============================================
    [ INFO: possible recursive locking detected ]
    4.2.0-armadillo-10725-g50fcd7643c034198 torvalds#781 Not tainted
    ---------------------------------------------
    s2ram/1179 is trying to acquire lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    but task is already holding lock:
    (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    other info that might help us debug this:
    Possible unsafe locking scenario:

	  CPU0
	  ----
     lock(&irq_desc_lock_class);
     lock(&irq_desc_lock_class);

    *** DEADLOCK ***

    May be due to missing lock nesting notation

    7 locks held by s2ram/1179:
    #0:  (sb_writers#7){.+.+.+}, at: [<c00c9708>] __sb_start_write+0x64/0xb8
    #1:  (&of->mutex){+.+.+.}, at: [<c0125a00>] kernfs_fop_write+0x78/0x1a0
    #2:  (s_active#23){.+.+.+}, at: [<c0125a08>] kernfs_fop_write+0x80/0x1a0
    #3:  (autosleep_lock){+.+.+.}, at: [<c0058244>] pm_autosleep_lock+0x18/0x20
    #4:  (pm_mutex){+.+.+.}, at: [<c0057e50>] pm_suspend+0x54/0x248
    #5:  (&dev->mutex){......}, at: [<c0243a20>] __device_suspend+0xdc/0x240
    #6:  (&irq_desc_lock_class){-.-...}, at: [<c005bb54>] __irq_get_desc_lock+0x78/0x94

    stack backtrace:
    CPU: 0 PID: 1179 Comm: s2ram Not tainted 4.2.0-armadillo-10725-g50fcd7643c034198

    Hardware name: Generic R8A7740 (Flattened Device Tree)
    [<c00129f4>] (dump_backtrace) from [<c0012bec>] (show_stack+0x18/0x1c)
    [<c0012bd4>] (show_stack) from [<c03f5d94>] (dump_stack+0x20/0x28)
    [<c03f5d74>] (dump_stack) from [<c00514d4>] (__lock_acquire+0x67c/0x1b88)
    [<c0050e58>] (__lock_acquire) from [<c0052df8>] (lock_acquire+0x9c/0xbc)
    [<c0052d5c>] (lock_acquire) from [<c03fb068>] (_raw_spin_lock_irqsave+0x44/0x58)
    [<c03fb024>] (_raw_spin_lock_irqsave) from [<c005bb54>] (__irq_get_desc_lock+0x78/0x94
    [<c005badc>] (__irq_get_desc_lock) from [<c005c3d8>] (irq_set_irq_wake+0x28/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c01e50d0>] (intc_irqpin_irq_set_wake+0x24/0x4c)
    [<c01e50ac>] (intc_irqpin_irq_set_wake) from [<c005c17c>] (set_irq_wake_real+0x3c/0x50
    [<c005c140>] (set_irq_wake_real) from [<c005c414>] (irq_set_irq_wake+0x64/0x100)
    [<c005c3b0>] (irq_set_irq_wake) from [<c02a19b4>] (gpio_keys_suspend+0x60/0xa0)
    [<c02a1954>] (gpio_keys_suspend) from [<c023b750>] (platform_pm_suspend+0x3c/0x5c)

Avoid this false positive by using a separate lockdep class for INTC
External IRQ Pin interrupts.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Cc: Grygorii Strashko <[email protected]>
Cc: Magnus Damm <[email protected]>
Cc: Jason Cooper <[email protected]>
Link: http://lkml.kernel.org/r/1441798974-25716-3-git-send-email-geert%[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 29, 2015
The OPP list needs to be protected against concurrent accesses. Using
simple RCU read locks does the trick and gets rid of the following
lockdep warning:

	===============================
	[ INFO: suspicious RCU usage. ]
	4.2.0-next-20150908 #1 Not tainted
	-------------------------------
	drivers/base/power/opp.c:460 Missing rcu_read_lock() or dev_opp_list_lock protection!

	other info that might help us debug this:

	rcu_scheduler_active = 1, debug_locks = 0
	4 locks held by kworker/u8:0/6:
	 #0:  ("%s""deferwq"){++++.+}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 #1:  (deferred_probe_work){+.+.+.}, at: [<c0040d8c>] process_one_work+0x118/0x4bc
	 #2:  (&dev->mutex){......}, at: [<c03b8194>] __device_attach+0x20/0x118
	 #3:  (prepare_lock){+.+...}, at: [<c054bc08>] clk_prepare_lock+0x10/0xf8

	stack backtrace:
	CPU: 2 PID: 6 Comm: kworker/u8:0 Not tainted 4.2.0-next-20150908 #1
	Hardware name: NVIDIA Tegra SoC (Flattened Device Tree)
	Workqueue: deferwq deferred_probe_work_func
	[<c001802c>] (unwind_backtrace) from [<c00135a4>] (show_stack+0x10/0x14)
	[<c00135a4>] (show_stack) from [<c02a8418>] (dump_stack+0x94/0xd4)
	[<c02a8418>] (dump_stack) from [<c03c6f6c>] (dev_pm_opp_find_freq_ceil+0x108/0x114)
	[<c03c6f6c>] (dev_pm_opp_find_freq_ceil) from [<c0551a3c>] (dfll_calculate_rate_request+0xb8/0x170)
	[<c0551a3c>] (dfll_calculate_rate_request) from [<c0551b10>] (dfll_clk_round_rate+0x1c/0x2c)
	[<c0551b10>] (dfll_clk_round_rate) from [<c054de2c>] (clk_calc_new_rates+0x1b8/0x228)
	[<c054de2c>] (clk_calc_new_rates) from [<c054e44c>] (clk_core_set_rate_nolock+0x44/0xac)
	[<c054e44c>] (clk_core_set_rate_nolock) from [<c054e4d8>] (clk_set_rate+0x24/0x34)
	[<c054e4d8>] (clk_set_rate) from [<c0512460>] (tegra124_cpufreq_probe+0x120/0x230)
	[<c0512460>] (tegra124_cpufreq_probe) from [<c03b9cbc>] (platform_drv_probe+0x44/0xac)
	[<c03b9cbc>] (platform_drv_probe) from [<c03b84c8>] (driver_probe_device+0x218/0x304)
	[<c03b84c8>] (driver_probe_device) from [<c03b69b0>] (bus_for_each_drv+0x60/0x94)
	[<c03b69b0>] (bus_for_each_drv) from [<c03b8228>] (__device_attach+0xb4/0x118)
	ata1: SATA link down (SStatus 0 SControl 300)
	[<c03b8228>] (__device_attach) from [<c03b77c8>] (bus_probe_device+0x88/0x90)
	[<c03b77c8>] (bus_probe_device) from [<c03b7be8>] (deferred_probe_work_func+0x58/0x8c)
	[<c03b7be8>] (deferred_probe_work_func) from [<c0040dfc>] (process_one_work+0x188/0x4bc)
	[<c0040dfc>] (process_one_work) from [<c004117c>] (worker_thread+0x4c/0x4f4)
	[<c004117c>] (worker_thread) from [<c0047230>] (kthread+0xe4/0xf8)
	[<c0047230>] (kthread) from [<c000f7d0>] (ret_from_fork+0x14/0x24)

Signed-off-by: Thierry Reding <[email protected]>
Fixes: c4fe70a ("clk: tegra: Add closed loop support for the DFLL")
[[email protected]: Unlock rcu on error path]
Signed-off-by: Vince Hsu <[email protected]>
[[email protected]: Dropped second hunk that nested the rcu
read lock unnecessarily]
Signed-off-by: Stephen Boyd <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 13, 2015
…t initialized.

In case something goes wrong with power well initialization we were calling
intel_prepare_ddi during boot while encoder list isnt't initilized.

[    9.618747] i915 0000:00:02.0: Invalid ROM contents
[    9.631446] [drm] failed to find VBIOS tables
[    9.720036] BUG: unable to handle kernel NULL pointer dereference at 00000000
00000058
[    9.721986] IP: [<ffffffffa014eb72>] ddi_get_encoder_port+0x82/0x190 [i915]
[    9.723736] PGD 0
[    9.724286] Oops: 0000 [#1] PREEMPT SMP
[    9.725386] Modules linked in: intel_powerclamp snd_hda_intel(+) coretemp crc
32c_intel snd_hda_codec snd_hda_core serio_raw snd_pcm snd_timer i915(+) parport
_pc parport pinctrl_sunrisepoint pinctrl_intel nfsd nfs_acl
[    9.730635] CPU: 0 PID: 497 Comm: systemd-udevd Not tainted 4.3.0-rc2-eywa-10
967-g72de2cfd-dirty #2
[    9.732785] Hardware name: Intel Corporation Cannonlake Client platform/Skyla
ke DT DDR4 RVP8, BIOS CNLSE2R1.R00.X021.B00.1508040310 08/04/2015
[    9.735785] task: ffff88008a704700 ti: ffff88016a1ac000 task.ti: ffff88016a1a
c000
[    9.737584] RIP: 0010:[<ffffffffa014eb72>]  [<ffffffffa014eb72>] ddi_get_enco
der_port+0x82/0x190 [i915]
[    9.739934] RSP: 0000:ffff88016a1af710  EFLAGS: 00010296
[    9.741184] RAX: 000000000000004e RBX: ffff88008a9edc98 RCX: 0000000000000001
[    9.742934] RDX: 000000000000004e RSI: ffffffff81fc1e82 RDI: 00000000ffffffff
[    9.744634] RBP: ffff88016a1af730 R08: 0000000000000000 R09: 0000000000000578
[    9.746333] R10: 0000000000001065 R11: 0000000000000578 R12: fffffffffffffff8
[    9.748033] R13: ffff88016a1af7a8 R14: ffff88016a1af794 R15: 0000000000000000
[    9.749733] FS:  00007eff2e1e07c0(0000) GS:ffff88016fc00000(0000) knlGS:00000
00000000000
[    9.751683] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    9.753083] CR2: 0000000000000058 CR3: 000000016922b000 CR4: 00000000003406f0
[    9.754782] Stack:
[    9.755332]  ffff88008a9edc98 ffff88008a9ed800 ffffffffa01d07b0 00000000fffb9
09e
[    9.757232]  ffff88016a1af7d8 ffffffffa0154ea7 0000000000000246 ffff88016a370
080
[    9.759182]  ffff88016a370080 ffff88008a9ed800 0000000000000246 ffff88008a9ed
c98
[    9.761132] Call Trace:
[    9.761782]  [<ffffffffa0154ea7>] intel_prepare_ddi+0x67/0x860 [i915]
[    9.763332]  [<ffffffff81a56996>] ? _raw_spin_unlock_irqrestore+0x26/0x40
[    9.765031]  [<ffffffffa00fad01>] ? gen9_read32+0x141/0x360 [i915]
[    9.766531]  [<ffffffffa00b43e1>] skl_set_power_well+0x431/0xa80 [i915]
[    9.768181]  [<ffffffffa00b4a63>] skl_power_well_enable+0x13/0x20 [i915]
[    9.769781]  [<ffffffffa00b2188>] intel_power_well_enable+0x28/0x50 [i915]
[    9.771481]  [<ffffffffa00b4d52>] intel_display_power_get+0x92/0xc0 [i915]
[    9.773180]  [<ffffffffa00b4fcb>] intel_display_set_init_power+0x3b/0x40 [i91
5]
[    9.774980]  [<ffffffffa00b5170>] intel_power_domains_init_hw+0x120/0x520 [i9
15]
[    9.776780]  [<ffffffffa0194c61>] i915_driver_load+0xb21/0xf40 [i915]

So let's protect this case.

My first attempt was to remove the intel_prepare_ddi, but Daniel had pointed out
this is really needed to restore those registers values. And Imre pointed out
that this case was without the flag protection and this was actually where things
were going bad. So I've just checked and this indeed solves my issue.

The regressing intel_prepare_ddi call was added in

commit 1d2b952
Author: Damien Lespiau <[email protected]>
Date:   Fri Mar 6 18:50:53 2015 +0000

    drm/i915/skl: Restore the DDI translation tables when enabling PW1

Cc: Imre Deak <[email protected]>
Cc: Daniel Vetter <[email protected]>
Signed-off-by: Rodrigo Vivi <[email protected]>
Reviewed-by: Imre Deak <[email protected]>
[Jani: regression reference]
Signed-off-by: Jani Nikula <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 13, 2015
Dmitry Vyukov reported the following using trinity and the memory
error detector AddressSanitizer
(https://code.google.com/p/address-sanitizer/wiki/AddressSanitizerForKernel).

[ 124.575597] ERROR: AddressSanitizer: heap-buffer-overflow on
address ffff88002e280000
[ 124.576801] ffff88002e280000 is located 131938492886538 bytes to
the left of 28857600-byte region [ffffffff81282e0a, ffffffff82e0830a)
[ 124.578633] Accessed by thread T10915:
[ 124.579295] inlined in describe_heap_address
./arch/x86/mm/asan/report.c:164
[ 124.579295] #0 ffffffff810dd277 in asan_report_error
./arch/x86/mm/asan/report.c:278
[ 124.580137] #1 ffffffff810dc6a0 in asan_check_region
./arch/x86/mm/asan/asan.c:37
[ 124.581050] #2 ffffffff810dd423 in __tsan_read8 ??:0
[ 124.581893] #3 ffffffff8107c093 in get_wchan
./arch/x86/kernel/process_64.c:444

The address checks in the 64bit implementation of get_wchan() are
wrong in several ways:

 - The lower bound of the stack is not the start of the stack
   page. It's the start of the stack page plus sizeof (struct
   thread_info)

 - The upper bound must be:

       top_of_stack - TOP_OF_KERNEL_STACK_PADDING - 2 * sizeof(unsigned long).

   The 2 * sizeof(unsigned long) is required because the stack pointer
   points at the frame pointer. The layout on the stack is: ... IP FP
   ... IP FP. So we need to make sure that both IP and FP are in the
   bounds.

Fix the bound checks and get rid of the mix of numeric constants, u64
and unsigned long. Making all unsigned long allows us to use the same
function for 32bit as well.

Use READ_ONCE() when accessing the stack. This does not prevent a
concurrent wakeup of the task and the stack changing, but at least it
avoids TOCTOU.

Also check task state at the end of the loop. Again that does not
prevent concurrent changes, but it avoids walking for nothing.

Add proper comments while at it.

Reported-by: Dmitry Vyukov <[email protected]>
Reported-by: Sasha Levin <[email protected]>
Based-on-patch-from: Wolfram Gloger <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Reviewed-by: Borislav Petkov <[email protected]>
Reviewed-by: Dmitry Vyukov <[email protected]>
Cc: Andrey Ryabinin <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Andrey Konovalov <[email protected]>
Cc: Kostya Serebryany <[email protected]>
Cc: Alexander Potapenko <[email protected]>
Cc: kasan-dev <[email protected]>
Cc: Denys Vlasenko <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Wolfram Gloger <[email protected]>
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Thomas Gleixner <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 13, 2015
Commit 1a3d595 ("MIPS: Tidy up FPU context switching") removed FP
context saving from the asm-written resume function in favour of reusing
existing code to perform the same task. However it only removed the FP
context saving code from the r4k_switch.S implementation of resume.
Octeon uses its own implementation in octeon_switch.S, so remove FP
context saving there too in order to prevent attempting to save context
twice. That formerly led to an exception from the second save as follows
because the FPU had already been disabled by the first save:

    do_cpu invoked from kernel context![#1]:
    CPU: 0 PID: 2 Comm: kthreadd Not tainted 4.3.0-rc2-dirty #2
    task: 800000041f84a008 ti: 800000041f864000 task.ti: 800000041f864000
    $ 0   : 0000000000000000 0000000010008ce1 0000000000100000 ffffffffbfffffff
    $ 4   : 800000041f84a008 800000041f84ac08 800000041f84c000 0000000000000004
    $ 8   : 0000000000000001 0000000000000000 0000000000000000 0000000000000001
    $12   : 0000000010008ce3 0000000000119c60 0000000000000036 800000041f864000
    $16   : 800000041f84ac08 800000000792ce80 800000041f84a008 ffffffff81758b00
    $20   : 0000000000000000 ffffffff8175ae50 0000000000000000 ffffffff8176c740
    $24   : 0000000000000006 ffffffff81170300
    $28   : 800000041f864000 800000041f867d90 0000000000000000 ffffffff815f3fa0
    Hi    : 0000000000fa8257
    Lo    : ffffffffe15cfc00
    epc   : ffffffff8112821c resume+0x9c/0x200
    ra    : ffffffff815f3fa0 __schedule+0x3f0/0x7d8
    Status: 10008ce2        KX SX UX KERNEL EXL
    Cause : 1080002c (ExcCode 0b)
    PrId  : 000d0601 (Cavium Octeon+)
    Modules linked in:
    Process kthreadd (pid: 2, threadinfo=800000041f864000, task=800000041f84a008, tls=0000000000000000)
    Stack : ffffffff81604218 ffffffff815f7e08 800000041f84a008 ffffffff811681b0
              800000041f84a008 ffffffff817e9878 0000000000000000 ffffffff81770000
              ffffffff81768340 ffffffff81161398 0000000000000001 0000000000000000
              0000000000000000 ffffffff815f4424 0000000000000000 ffffffff81161d68
              ffffffff81161be8 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 ffffffff8111e16c
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              0000000000000000 0000000000000000 0000000000000000 0000000000000000
              ...
    Call Trace:
    [<ffffffff8112821c>] resume+0x9c/0x200
    [<ffffffff815f3fa0>] __schedule+0x3f0/0x7d8
    [<ffffffff815f4424>] schedule+0x34/0x98
    [<ffffffff81161d68>] kthreadd+0x180/0x198
    [<ffffffff8111e16c>] ret_from_kernel_thread+0x14/0x1c

Tested using cavium_octeon_defconfig on an EdgeRouter Lite.

Fixes: 1a3d595 ("MIPS: Tidy up FPU context switching")
Reported-by: Aaro Koskinen <[email protected]>
Signed-off-by: Paul Burton <[email protected]>
Cc: [email protected]
Cc: Aleksey Makarov <[email protected]>
Cc: [email protected]
Cc: Chandrakala Chavva <[email protected]>
Cc: David Daney <[email protected]>
Cc: Leonid Rosenboim <[email protected]>
Patchwork: https://patchwork.linux-mips.org/patch/11166/
Signed-off-by: Ralf Baechle <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 13, 2015
My colleague ran into a program stall on a x86_64 server, where
n_tty_read() was waiting for data even if there was data in the buffer
in the pty.  kernel stack for the stuck process looks like below.
 #0 [ffff88303d107b58] __schedule at ffffffff815c4b20
 #1 [ffff88303d107bd0] schedule at ffffffff815c513e
 #2 [ffff88303d107bf0] schedule_timeout at ffffffff815c7818
 #3 [ffff88303d107ca0] wait_woken at ffffffff81096bd2
 #4 [ffff88303d107ce0] n_tty_read at ffffffff8136fa23
 #5 [ffff88303d107dd0] tty_read at ffffffff81368013
 #6 [ffff88303d107e20] __vfs_read at ffffffff811a3704
 #7 [ffff88303d107ec0] vfs_read at ffffffff811a3a57
 #8 [ffff88303d107f00] sys_read at ffffffff811a4306
 #9 [ffff88303d107f50] entry_SYSCALL_64_fastpath at ffffffff815c86d7

There seems to be two problems causing this issue.

First, in drivers/tty/n_tty.c, __receive_buf() stores the data and
updates ldata->commit_head using smp_store_release() and then checks
the wait queue using waitqueue_active().  However, since there is no
memory barrier, __receive_buf() could return without calling
wake_up_interactive_poll(), and at the same time, n_tty_read() could
start to wait in wait_woken() as in the following chart.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
if (waitqueue_active(&tty->read_wait))
/* Memory operations issued after the
   RELEASE may be completed before the
   RELEASE operation has completed */
                                        add_wait_queue(&tty->read_wait, &wait);
                                        ...
                                        if (!input_available_p(tty, 0)) {
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

The second problem is that n_tty_read() also lacks a memory barrier
call and could also cause __receive_buf() to return without calling
wake_up_interactive_poll(), and n_tty_read() to wait in wait_woken()
as in the chart below.

        __receive_buf()                         n_tty_read()
------------------------------------------------------------------------
                                        spin_lock_irqsave(&q->lock, flags);
                                        /* from add_wait_queue() */
                                        ...
                                        if (!input_available_p(tty, 0)) {
                                        /* Memory operations issued after the
                                           RELEASE may be completed before the
                                           RELEASE operation has completed */
smp_store_release(&ldata->commit_head,
                  ldata->read_head);
if (waitqueue_active(&tty->read_wait))
                                        __add_wait_queue(q, wait);
                                        spin_unlock_irqrestore(&q->lock,flags);
                                        /* from add_wait_queue() */
                                        ...
                                        timeout = wait_woken(&wait,
                                          TASK_INTERRUPTIBLE, timeout);
------------------------------------------------------------------------

There are also other places in drivers/tty/n_tty.c which have similar
calls to waitqueue_active(), so instead of adding many memory barrier
calls, this patch simply removes the call to waitqueue_active(),
leaving just wake_up*() behind.

This fixes both problems because, even though the memory access before
or after the spinlocks in both wake_up*() and add_wait_queue() can
sneak into the critical section, it cannot go past it and the critical
section assures that they will be serialized (please see "INTER-CPU
ACQUIRING BARRIER EFFECTS" in Documentation/memory-barriers.txt for a
better explanation).  Moreover, the resulting code is much simpler.

Latency measurement using a ping-pong test over a pty doesn't show any
visible performance drop.

Signed-off-by: Kosuke Tatsukawa <[email protected]>
Cc: [email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 13, 2015
When running kprobe test on arm64 rt kernel, it reports the below warning:

root@qemu7:~# modprobe kprobe_example
BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:917
in_atomic(): 0, irqs_disabled(): 128, pid: 484, name: modprobe
CPU: 0 PID: 484 Comm: modprobe Not tainted 4.1.6-rt5 #2
Hardware name: linux,dummy-virt (DT)
Call trace:
[<ffffffc0000891b8>] dump_backtrace+0x0/0x128
[<ffffffc000089300>] show_stack+0x20/0x30
[<ffffffc00061dae8>] dump_stack+0x1c/0x28
[<ffffffc0000bbad0>] ___might_sleep+0x120/0x198
[<ffffffc0006223e8>] rt_spin_lock+0x28/0x40
[<ffffffc000622b30>] __aarch64_insn_write+0x28/0x78
[<ffffffc000622e48>] aarch64_insn_patch_text_nosync+0x18/0x48
[<ffffffc000622ee8>] aarch64_insn_patch_text_cb+0x70/0xa0
[<ffffffc000622f40>] aarch64_insn_patch_text_sync+0x28/0x48
[<ffffffc0006236e0>] arch_arm_kprobe+0x38/0x48
[<ffffffc00010e6f4>] arm_kprobe+0x34/0x50
[<ffffffc000110374>] register_kprobe+0x4cc/0x5b8
[<ffffffbffc002038>] kprobe_init+0x38/0x7c [kprobe_example]
[<ffffffc000084240>] do_one_initcall+0x90/0x1b0
[<ffffffc00061c498>] do_init_module+0x6c/0x1cc
[<ffffffc0000fd0c0>] load_module+0x17f8/0x1db0
[<ffffffc0000fd8cc>] SyS_finit_module+0xb4/0xc8

Convert patch_lock to raw loc kto avoid this issue.

Although the problem is found on rt kernel, the fix should be applicable to
mainline kernel too.

Acked-by: Steven Rostedt <[email protected]>
Signed-off-by: Yang Shi <[email protected]>
Signed-off-by: Will Deacon <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 3, 2025
Fix cifs_signal_cifsd_for_reconnect() to take the correct lock order
and prevent the following deadlock from happening

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc3-build2+ torvalds#1301 Tainted: G S      W
------------------------------------------------------
cifsd/6055 is trying to acquire lock:
ffff88810ad56038 (&tcp_ses->srv_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x134/0x200

but task is already holding lock:
ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (&ret_buf->chan_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_setup_session+0x81/0x4b0
       cifs_get_smb_ses+0x771/0x900
       cifs_mount_get_session+0x7e/0x170
       cifs_mount+0x92/0x2d0
       cifs_smb3_do_mount+0x161/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #1 (&ret_buf->ses_lock){+.+.}-{3:3}:
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_match_super+0x101/0x320
       sget+0xab/0x270
       cifs_smb3_do_mount+0x1e0/0x460
       smb3_get_tree+0x55/0x90
       vfs_get_tree+0x46/0x180
       do_new_mount+0x1b0/0x2e0
       path_mount+0x6ee/0x740
       do_mount+0x98/0xe0
       __do_sys_mount+0x148/0x180
       do_syscall_64+0xa4/0x260
       entry_SYSCALL_64_after_hwframe+0x76/0x7e

-> #0 (&tcp_ses->srv_lock){+.+.}-{3:3}:
       check_noncircular+0x95/0xc0
       check_prev_add+0x115/0x2f0
       validate_chain+0x1cf/0x270
       __lock_acquire+0x60e/0x780
       lock_acquire.part.0+0xb4/0x1f0
       _raw_spin_lock+0x2f/0x40
       cifs_signal_cifsd_for_reconnect+0x134/0x200
       __cifs_reconnect+0x8f/0x500
       cifs_handle_standard+0x112/0x280
       cifs_demultiplex_thread+0x64d/0xbc0
       kthread+0x2f7/0x310
       ret_from_fork+0x2a/0x230
       ret_from_fork_asm+0x1a/0x30

other info that might help us debug this:

Chain exists of:
  &tcp_ses->srv_lock --> &ret_buf->ses_lock --> &ret_buf->chan_lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ret_buf->chan_lock);
                               lock(&ret_buf->ses_lock);
                               lock(&ret_buf->chan_lock);
  lock(&tcp_ses->srv_lock);

 *** DEADLOCK ***

3 locks held by cifsd/6055:
 #0: ffffffff857de398 (&cifs_tcp_ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x7b/0x200
 #1: ffff888119c64060 (&ret_buf->ses_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0x9c/0x200
 #2: ffff888119c64330 (&ret_buf->chan_lock){+.+.}-{3:3}, at: cifs_signal_cifsd_for_reconnect+0xcf/0x200

Cc: [email protected]
Reported-by: David Howells <[email protected]>
Fixes: d7d7a66 ("cifs: avoid use of global locks for high contention data")
Reviewed-by: David Howells <[email protected]>
Tested-by: David Howells <[email protected]>
Signed-off-by: Paulo Alcantara (Red Hat) <[email protected]>
Signed-off-by: David Howells <[email protected]>
Signed-off-by: Steve French <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 6, 2025
When I run the NVME over TCP test in virtme-ng, I get the following
"suspicious RCU usage" warning in nvme_mpath_add_sysfs_link():

'''
[    5.024557][   T44] nvmet: Created nvm controller 1 for subsystem nqn.2025-06.org.nvmexpress.mptcp for NQN nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77.
[    5.027401][  T183] nvme nvme0: creating 2 I/O queues.
[    5.029017][  T183] nvme nvme0: mapped 2/0/0 default/read/poll queues.
[    5.032587][  T183] nvme nvme0: new ctrl: NQN "nqn.2025-06.org.nvmexpress.mptcp", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77
[    5.042214][   T25]
[    5.042440][   T25] =============================
[    5.042579][   T25] WARNING: suspicious RCU usage
[    5.042705][   T25] 6.16.0-rc3+ linux-sunxi#23 Not tainted
[    5.042812][   T25] -----------------------------
[    5.042934][   T25] drivers/nvme/host/multipath.c:1203 RCU-list traversed in non-reader section!!
[    5.043111][   T25]
[    5.043111][   T25] other info that might help us debug this:
[    5.043111][   T25]
[    5.043341][   T25]
[    5.043341][   T25] rcu_scheduler_active = 2, debug_locks = 1
[    5.043502][   T25] 3 locks held by kworker/u9:0/25:
[    5.043615][   T25]  #0: ffff888008730948 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x7ed/0x1350
[    5.043830][   T25]  #1: ffffc900001afd40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0xcf3/0x1350
[    5.044084][   T25]  #2: ffff888013ee0020 (&head->srcu){.+.+}-{0:0}, at: nvme_mpath_add_sysfs_link.part.0+0xb4/0x3a0
[    5.044300][   T25]
[    5.044300][   T25] stack backtrace:
[    5.044439][   T25] CPU: 0 UID: 0 PID: 25 Comm: kworker/u9:0 Not tainted 6.16.0-rc3+ linux-sunxi#23 PREEMPT(full)
[    5.044441][   T25] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    5.044442][   T25] Workqueue: async async_run_entry_fn
[    5.044445][   T25] Call Trace:
[    5.044446][   T25]  <TASK>
[    5.044449][   T25]  dump_stack_lvl+0x6f/0xb0
[    5.044453][   T25]  lockdep_rcu_suspicious.cold+0x4f/0xb1
[    5.044457][   T25]  nvme_mpath_add_sysfs_link.part.0+0x2fb/0x3a0
[    5.044459][   T25]  ? queue_work_on+0x90/0xf0
[    5.044461][   T25]  ? lockdep_hardirqs_on+0x78/0x110
[    5.044466][   T25]  nvme_mpath_set_live+0x1e9/0x4f0
[    5.044470][   T25]  nvme_mpath_add_disk+0x240/0x2f0
[    5.044472][   T25]  ? __pfx_nvme_mpath_add_disk+0x10/0x10
[    5.044475][   T25]  ? add_disk_fwnode+0x361/0x580
[    5.044480][   T25]  nvme_alloc_ns+0x81c/0x17c0
[    5.044483][   T25]  ? kasan_quarantine_put+0x104/0x240
[    5.044487][   T25]  ? __pfx_nvme_alloc_ns+0x10/0x10
[    5.044495][   T25]  ? __pfx_nvme_find_get_ns+0x10/0x10
[    5.044496][   T25]  ? rcu_read_lock_any_held+0x45/0xa0
[    5.044498][   T25]  ? validate_chain+0x232/0x4f0
[    5.044503][   T25]  nvme_scan_ns+0x4c8/0x810
[    5.044506][   T25]  ? __pfx_nvme_scan_ns+0x10/0x10
[    5.044508][   T25]  ? find_held_lock+0x2b/0x80
[    5.044512][   T25]  ? ktime_get+0x16d/0x220
[    5.044517][   T25]  ? kvm_clock_get_cycles+0x18/0x30
[    5.044520][   T25]  ? __pfx_nvme_scan_ns_async+0x10/0x10
[    5.044522][   T25]  async_run_entry_fn+0x97/0x560
[    5.044523][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044526][   T25]  process_one_work+0xd3c/0x1350
[    5.044532][   T25]  ? __pfx_process_one_work+0x10/0x10
[    5.044536][   T25]  ? assign_work+0x16c/0x240
[    5.044539][   T25]  worker_thread+0x4da/0xd50
[    5.044545][   T25]  ? __pfx_worker_thread+0x10/0x10
[    5.044546][   T25]  kthread+0x356/0x5c0
[    5.044548][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044549][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044552][   T25]  ? __lock_release.isra.0+0x5d/0x180
[    5.044553][   T25]  ? ret_from_fork+0x1b/0x2e0
[    5.044555][   T25]  ? rcu_is_watching+0x12/0xc0
[    5.044557][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044559][   T25]  ret_from_fork+0x218/0x2e0
[    5.044561][   T25]  ? __pfx_kthread+0x10/0x10
[    5.044562][   T25]  ret_from_fork_asm+0x1a/0x30
[    5.044570][   T25]  </TASK>
'''

This patch uses sleepable RCU version of helper list_for_each_entry_srcu()
instead of list_for_each_entry_rcu() to fix it.

Fixes: 4dbd2b2 ("nvme-multipath: Add visibility for round-robin io-policy")
Signed-off-by: Geliang Tang <[email protected]>
Reviewed-by: Keith Busch <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Nilay Shroff <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Jul 6, 2025
With VIRTCHNL2_CAP_MACFILTER enabled, the following warning is generated
on module load:

[  324.701677] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:578
[  324.701684] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1582, name: NetworkManager
[  324.701689] preempt_count: 201, expected: 0
[  324.701693] RCU nest depth: 0, expected: 0
[  324.701697] 2 locks held by NetworkManager/1582:
[  324.701702]  #0: ffffffff9f7be770 (rtnl_mutex){....}-{3:3}, at: rtnl_newlink+0x791/0x21e0
[  324.701730]  #1: ff1100216c380368 (_xmit_ETHER){....}-{2:2}, at: __dev_open+0x3f0/0x870
[  324.701749] Preemption disabled at:
[  324.701752] [<ffffffff9cd23b9d>] __dev_open+0x3dd/0x870
[  324.701765] CPU: 30 UID: 0 PID: 1582 Comm: NetworkManager Not tainted 6.15.0-rc5+ #2 PREEMPT(voluntary)
[  324.701771] Hardware name: Intel Corporation M50FCP2SBSTD/M50FCP2SBSTD, BIOS SE5C741.86B.01.01.0001.2211140926 11/14/2022
[  324.701774] Call Trace:
[  324.701777]  <TASK>
[  324.701779]  dump_stack_lvl+0x5d/0x80
[  324.701788]  ? __dev_open+0x3dd/0x870
[  324.701793]  __might_resched.cold+0x1ef/0x23d
<..>
[  324.701818]  __mutex_lock+0x113/0x1b80
<..>
[  324.701917]  idpf_ctlq_clean_sq+0xad/0x4b0 [idpf]
[  324.701935]  ? kasan_save_track+0x14/0x30
[  324.701941]  idpf_mb_clean+0x143/0x380 [idpf]
<..>
[  324.701991]  idpf_send_mb_msg+0x111/0x720 [idpf]
[  324.702009]  idpf_vc_xn_exec+0x4cc/0x990 [idpf]
[  324.702021]  ? rcu_is_watching+0x12/0xc0
[  324.702035]  idpf_add_del_mac_filters+0x3ed/0xb50 [idpf]
<..>
[  324.702122]  __hw_addr_sync_dev+0x1cf/0x300
[  324.702126]  ? find_held_lock+0x32/0x90
[  324.702134]  idpf_set_rx_mode+0x317/0x390 [idpf]
[  324.702152]  __dev_open+0x3f8/0x870
[  324.702159]  ? __pfx___dev_open+0x10/0x10
[  324.702174]  __dev_change_flags+0x443/0x650
<..>
[  324.702208]  netif_change_flags+0x80/0x160
[  324.702218]  do_setlink.isra.0+0x16a0/0x3960
<..>
[  324.702349]  rtnl_newlink+0x12fd/0x21e0

The sequence is as follows:
	rtnl_newlink()->
	__dev_change_flags()->
	__dev_open()->
	dev_set_rx_mode() - >  # disables BH and grabs "dev->addr_list_lock"
	idpf_set_rx_mode() ->  # proceed only if VIRTCHNL2_CAP_MACFILTER is ON
	__dev_uc_sync() ->
	idpf_add_mac_filter ->
	idpf_add_del_mac_filters ->
	idpf_send_mb_msg() ->
	idpf_mb_clean() ->
	idpf_ctlq_clean_sq()   # mutex_lock(cq_lock)

Fix by converting cq_lock to a spinlock. All operations under the new
lock are safe except freeing the DMA memory, which may use vunmap(). Fix
by requesting a contiguous physical memory for the DMA mapping.

Fixes: a251eee ("idpf: add SRIOV support and other ndo_ops")
Reviewed-by: Aleksandr Loktionov <[email protected]>
Signed-off-by: Ahmed Zaki <[email protected]>
Reviewed-by: Simon Horman <[email protected]>
Tested-by: Samuel Salin <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 4, 2025
If the PHY driver uses another PHY internally (e.g. in case of eUSB2,
repeaters are represented as PHYs), then it would trigger the following
lockdep splat because all PHYs use a single static lockdep key and thus
lockdep can not identify whether there is a dependency or not and
reports a false positive.

Make PHY subsystem use dynamic lockdep keys, assigning each driver a
separate key. This way lockdep can correctly identify dependency graph
between mutexes.

 ============================================
 WARNING: possible recursive locking detected
 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 Not tainted
 --------------------------------------------
 kworker/u51:0/78 is trying to acquire lock:
 ffff0008116554f0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 but task is already holding lock:
 ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&phy->mutex);
   lock(&phy->mutex);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 4 locks held by kworker/u51:0/78:
  #0: ffff000800010948 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x18c/0x5ec
  #1: ffff80008036bdb0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x1b4/0x5ec
  #2: ffff0008094ac8f8 (&dev->mutex){....}-{4:4}, at: __device_attach+0x38/0x188
  #3: ffff000813c10cf0 (&phy->mutex){+.+.}-{4:4}, at: phy_init+0x4c/0x12c

 stack backtrace:
 CPU: 0 UID: 0 PID: 78 Comm: kworker/u51:0 Not tainted 6.15.0-rc7-next-20250522-12896-g3932f283970c #3455 PREEMPT
 Hardware name: Qualcomm CRD, BIOS 6.0.240904.BOOT.MXF.2.4-00528.1-HAMOA-1 09/ 4/2024
 Workqueue: events_unbound deferred_probe_work_func
 Call trace:
  show_stack+0x18/0x24 (C)
  dump_stack_lvl+0x90/0xd0
  dump_stack+0x18/0x24
  print_deadlock_bug+0x258/0x348
  __lock_acquire+0x10fc/0x1f84
  lock_acquire+0x1c8/0x338
  __mutex_lock+0xb8/0x59c
  mutex_lock_nested+0x24/0x30
  phy_init+0x4c/0x12c
  snps_eusb2_hsphy_init+0x54/0x1a0
  phy_init+0xe0/0x12c
  dwc3_core_init+0x450/0x10b4
  dwc3_core_probe+0xce4/0x15fc
  dwc3_probe+0x64/0xb0
  platform_probe+0x68/0xc4
  really_probe+0xbc/0x298
  __driver_probe_device+0x78/0x12c
  driver_probe_device+0x3c/0x160
  __device_attach_driver+0xb8/0x138
  bus_for_each_drv+0x84/0xe0
  __device_attach+0x9c/0x188
  device_initial_probe+0x14/0x20
  bus_probe_device+0xac/0xb0
  deferred_probe_work_func+0x8c/0xc8
  process_one_work+0x208/0x5ec
  worker_thread+0x1c0/0x368
  kthread+0x14c/0x20c
  ret_from_fork+0x10/0x20

Fixes: 3584f63 ("phy: qcom: phy-qcom-snps-eusb2: Add support for eUSB2 repeater")
Fixes: e246355 ("phy: amlogic: Add Amlogic AXG PCIE PHY Driver")
Reviewed-by: Neil Armstrong <[email protected]>
Reviewed-by: Abel Vesa <[email protected]>
Reported-by: Johan Hovold <[email protected]>
Link: https://lore.kernel.org/lkml/[email protected]/
Reviewed-by: Johan Hovold <[email protected]>
Tested-by: Johan Hovold <[email protected]>
Signed-off-by: Dmitry Baryshkov <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 4, 2025
…-flight

Reject migration of SEV{-ES} state if either the source or destination VM
is actively creating a vCPU, i.e. if kvm_vm_ioctl_create_vcpu() is in the
section between incrementing created_vcpus and online_vcpus.  The bulk of
vCPU creation runs _outside_ of kvm->lock to allow creating multiple vCPUs
in parallel, and so sev_info.es_active can get toggled from false=>true in
the destination VM after (or during) svm_vcpu_create(), resulting in an
SEV{-ES} VM effectively having a non-SEV{-ES} vCPU.

The issue manifests most visibly as a crash when trying to free a vCPU's
NULL VMSA page in an SEV-ES VM, but any number of things can go wrong.

  BUG: unable to handle page fault for address: ffffebde00000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 0 P4D 0
  Oops: Oops: 0000 [#1] SMP KASAN NOPTI
  CPU: 227 UID: 0 PID: 64063 Comm: syz.5.60023 Tainted: G     U     O        6.15.0-smp-DEV #2 NONE
  Tainted: [U]=USER, [O]=OOT_MODULE
  Hardware name: Google, Inc. Arcadia_IT_80/Arcadia_IT_80, BIOS 12.52.0-0 10/28/2024
  RIP: 0010:constant_test_bit arch/x86/include/asm/bitops.h:206 [inline]
  RIP: 0010:arch_test_bit arch/x86/include/asm/bitops.h:238 [inline]
  RIP: 0010:_test_bit include/asm-generic/bitops/instrumented-non-atomic.h:142 [inline]
  RIP: 0010:PageHead include/linux/page-flags.h:866 [inline]
  RIP: 0010:___free_pages+0x3e/0x120 mm/page_alloc.c:5067
  Code: <49> f7 06 40 00 00 00 75 05 45 31 ff eb 0c 66 90 4c 89 f0 4c 39 f0
  RSP: 0018:ffff8984551978d0 EFLAGS: 00010246
  RAX: 0000777f80000001 RBX: 0000000000000000 RCX: ffffffff918aeb98
  RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffebde00000000
  RBP: 0000000000000000 R08: ffffebde00000007 R09: 1ffffd7bc0000000
  R10: dffffc0000000000 R11: fffff97bc0000001 R12: dffffc0000000000
  R13: ffff8983e19751a8 R14: ffffebde00000000 R15: 1ffffd7bc0000000
  FS:  0000000000000000(0000) GS:ffff89ee661d3000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffebde00000000 CR3: 000000793ceaa000 CR4: 0000000000350ef0
  DR0: 0000000000000000 DR1: 0000000000000b5f DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
  Call Trace:
   <TASK>
   sev_free_vcpu+0x413/0x630 arch/x86/kvm/svm/sev.c:3169
   svm_vcpu_free+0x13a/0x2a0 arch/x86/kvm/svm/svm.c:1515
   kvm_arch_vcpu_destroy+0x6a/0x1d0 arch/x86/kvm/x86.c:12396
   kvm_vcpu_destroy virt/kvm/kvm_main.c:470 [inline]
   kvm_destroy_vcpus+0xd1/0x300 virt/kvm/kvm_main.c:490
   kvm_arch_destroy_vm+0x636/0x820 arch/x86/kvm/x86.c:12895
   kvm_put_kvm+0xb8e/0xfb0 virt/kvm/kvm_main.c:1310
   kvm_vm_release+0x48/0x60 virt/kvm/kvm_main.c:1369
   __fput+0x3e4/0x9e0 fs/file_table.c:465
   task_work_run+0x1a9/0x220 kernel/task_work.c:227
   exit_task_work include/linux/task_work.h:40 [inline]
   do_exit+0x7f0/0x25b0 kernel/exit.c:953
   do_group_exit+0x203/0x2d0 kernel/exit.c:1102
   get_signal+0x1357/0x1480 kernel/signal.c:3034
   arch_do_signal_or_restart+0x40/0x690 arch/x86/kernel/signal.c:337
   exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
   exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
   __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
   syscall_exit_to_user_mode+0x67/0xb0 kernel/entry/common.c:218
   do_syscall_64+0x7c/0x150 arch/x86/entry/syscall_64.c:100
   entry_SYSCALL_64_after_hwframe+0x76/0x7e
  RIP: 0033:0x7f87a898e969
   </TASK>
  Modules linked in: gq(O)
  gsmi: Log Shutdown Reason 0x03
  CR2: ffffebde00000000
  ---[ end trace 0000000000000000 ]---

Deliberately don't check for a NULL VMSA when freeing the vCPU, as crashing
the host is likely desirable due to the VMSA being consumed by hardware.
E.g. if KVM manages to allow VMRUN on the vCPU, hardware may read/write a
bogus VMSA page.  Accessing PFN 0 is "fine"-ish now that it's sequestered
away thanks to L1TF, but panicking in this scenario is preferable to
potentially running with corrupted state.

Reported-by: Alexander Potapenko <[email protected]>
Tested-by: Alexander Potapenko <[email protected]>
Fixes: 0b020f5 ("KVM: SEV: Add support for SEV-ES intra host migration")
Fixes: b566393 ("KVM: SEV: Add support for SEV intra host migration")
Cc: [email protected]
Cc: James Houghton <[email protected]>
Cc: Peter Gonda <[email protected]>
Reviewed-by: Liam Merwick <[email protected]>
Tested-by: Liam Merwick <[email protected]>
Reviewed-by: James Houghton <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 4, 2025
If "try_verify_in_tasklet" is set for dm-verity, DM_BUFIO_CLIENT_NO_SLEEP
is enabled for dm-bufio. However, when bufio tries to evict buffers, there
is a chance to trigger scheduling in spin_lock_bh, the following warning
is hit:

BUG: sleeping function called from invalid context at drivers/md/dm-bufio.c:2745
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 123, name: kworker/2:2
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
4 locks held by kworker/2:2/123:
 #0: ffff88800a2d1548 ((wq_completion)dm_bufio_cache){....}-{0:0}, at: process_one_work+0xe46/0x1970
 #1: ffffc90000d97d20 ((work_completion)(&dm_bufio_replacement_work)){....}-{0:0}, at: process_one_work+0x763/0x1970
 #2: ffffffff8555b528 (dm_bufio_clients_lock){....}-{3:3}, at: do_global_cleanup+0x1ce/0x710
 #3: ffff88801d5820b8 (&c->spinlock){....}-{2:2}, at: do_global_cleanup+0x2a5/0x710
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 2 UID: 0 PID: 123 Comm: kworker/2:2 Not tainted 6.16.0-rc3-g90548c634bd0 linux-sunxi#305 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.3-0-ga6ed6b701f0a-prebuilt.qemu.org 04/01/2014
Workqueue: dm_bufio_cache do_global_cleanup
Call Trace:
 <TASK>
 dump_stack_lvl+0x53/0x70
 __might_resched+0x360/0x4e0
 do_global_cleanup+0x2f5/0x710
 process_one_work+0x7db/0x1970
 worker_thread+0x518/0xea0
 kthread+0x359/0x690
 ret_from_fork+0xf3/0x1b0
 ret_from_fork_asm+0x1a/0x30
 </TASK>

That can be reproduced by:

  veritysetup format --data-block-size=4096 --hash-block-size=4096 /dev/vda /dev/vdb
  SIZE=$(blockdev --getsz /dev/vda)
  dmsetup create myverity -r --table "0 $SIZE verity 1 /dev/vda /dev/vdb 4096 4096 <data_blocks> 1 sha256 <root_hash> <salt> 1 try_verify_in_tasklet"
  mount /dev/dm-0 /mnt -o ro
  echo 102400 > /sys/module/dm_bufio/parameters/max_cache_size_bytes
  [read files in /mnt]

Cc: [email protected]	# v6.4+
Fixes: 450e8de ("dm bufio: improve concurrent IO performance")
Signed-off-by: Wang Shuai <[email protected]>
Signed-off-by: Sheng Yong <[email protected]>
Signed-off-by: Mikulas Patocka <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 4, 2025
This reverts commit 7796c97.

This patch broke Dragonboard 845c (sdm845). I see:

    Unexpected kernel BRK exception at EL1
    Internal error: BRK handler: 00000000f20003e8 [#1]  SMP
    pc : qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom]
    lr : snd_soc_dai_set_channel_map+0x34/0x78
    Call trace:
     qcom_swrm_set_channel_map+0x7c/0x80 [soundwire_qcom] (P)
     sdm845_dai_init+0x18c/0x2e0 [snd_soc_sdm845]
     snd_soc_link_init+0x28/0x6c
     snd_soc_bind_card+0x5f4/0xb0c
     snd_soc_register_card+0x148/0x1a4
     devm_snd_soc_register_card+0x50/0xb0
     sdm845_snd_platform_probe+0x124/0x148 [snd_soc_sdm845]
     platform_probe+0x6c/0xd0
     really_probe+0xc0/0x2a4
     __driver_probe_device+0x7c/0x130
     driver_probe_device+0x40/0x118
     __device_attach_driver+0xc4/0x108
     bus_for_each_drv+0x8c/0xf0
     __device_attach+0xa4/0x198
     device_initial_probe+0x18/0x28
     bus_probe_device+0xb8/0xbc
     deferred_probe_work_func+0xac/0xfc
     process_one_work+0x244/0x658
     worker_thread+0x1b4/0x360
     kthread+0x148/0x228
     ret_from_fork+0x10/0x20
    Kernel panic - not syncing: BRK handler: Fatal exception

Dan has also reported following issues with the original patch
https://lore.kernel.org/all/[email protected]/

Bug #1:
The zeroeth element of ctrl->pconfig[] is supposed to be unused.  We
start counting at 1.  However this code sets ctrl->pconfig[0].ch_mask = 128.

Bug #2:
There are SLIM_MAX_TX_PORTS (16) elements in tx_ch[] array but only
QCOM_SDW_MAX_PORTS + 1 (15) in the ctrl->pconfig[] array so it corrupts
memory like Yongqin Liu pointed out.

Bug 3:
Like Jie Gan pointed out, it erases all the tx information with the rx
information.

Cc: [email protected] # v6.15+
Signed-off-by: Amit Pundir <[email protected]>
Acked-by: Srinivas Kandagatla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Vinod Koul <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 4, 2025
 into HEAD

KVM/riscv fixes for 6.16, take #2

- Disable vstimecmp before exiting to user-space
- Move HGEI[E|P] CSR access to IMSIC virtualization
jwrdegoede pushed a commit that referenced this pull request Aug 31, 2025
These iterations require the read lock, otherwise RCU
lockdep will splat:

=============================
WARNING: suspicious RCU usage
6.17.0-rc3-00014-g31419c045d64 #6 Tainted: G           O
-----------------------------
drivers/base/power/main.c:1333 RCU-list traversed in non-reader section!!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
5 locks held by rtcwake/547:
 #0: 00000000643ab418 (sb_writers#6){.+.+}-{0:0}, at: file_start_write+0x2b/0x3a
 #1: 0000000067a0ca88 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x181/0x24b
 #2: 00000000631eac40 (kn->active#3){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x191/0x24b
 #3: 00000000609a1308 (system_transition_mutex){+.+.}-{4:4}, at: pm_suspend+0xaf/0x30b
 #4: 0000000060c0fdb0 (device_links_srcu){.+.+}-{0:0}, at: device_links_read_lock+0x75/0x98

stack backtrace:
CPU: 0 UID: 0 PID: 547 Comm: rtcwake Tainted: G           O        6.17.0-rc3-00014-g31419c045d64 #6 VOLUNTARY
Tainted: [O]=OOT_MODULE
Stack:
 223721b3a80 6089eac6 00000001 00000001
 ffffff00 6089eac6 00000535 6086e528
 721b3ac0 6003c294 00000000 60031fc0
Call Trace:
 [<600407ed>] show_stack+0x10e/0x127
 [<6003c294>] dump_stack_lvl+0x77/0xc6
 [<6003c2fd>] dump_stack+0x1a/0x20
 [<600bc2f8>] lockdep_rcu_suspicious+0x116/0x13e
 [<603d8ea1>] dpm_async_suspend_superior+0x117/0x17e
 [<603d980f>] device_suspend+0x528/0x541
 [<603da24b>] dpm_suspend+0x1a2/0x267
 [<603da837>] dpm_suspend_start+0x5d/0x72
 [<600ca0c9>] suspend_devices_and_enter+0xab/0x736
 [...]

Add the fourth argument to the iteration to annotate
this and avoid the splat.

Fixes: 0679963 ("PM: sleep: Make async suspend handle suppliers like parents")
Fixes: ed18738 ("PM: sleep: Make async resume handle consumers like children")
Signed-off-by: Johannes Berg <[email protected]>
Link: https://patch.msgid.link/20250826134348.aba79f6e6299.I9ecf55da46ccf33778f2c018a82e1819d815b348@changeid
Signed-off-by: Rafael J. Wysocki <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 31, 2025
With CONFIG_DEBUG_OBJECTS_TIMERS unloading hfcpci module leads
to the following splat:

[  250.215892] ODEBUG: assert_init not available (active state 0) object: ffffffffc01a3dc0 object type: timer_list hint: 0x0
[  250.217520] WARNING: CPU: 0 PID: 233 at lib/debugobjects.c:612 debug_print_object+0x1b6/0x2c0
[  250.218775] Modules linked in: hfcpci(-) mISDN_core
[  250.219537] CPU: 0 UID: 0 PID: 233 Comm: rmmod Not tainted 6.17.0-rc2-g6f713187ac98 #2 PREEMPT(voluntary)
[  250.220940] Hardware name: QEMU Ubuntu 24.04 PC (i440FX + PIIX, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[  250.222377] RIP: 0010:debug_print_object+0x1b6/0x2c0
[  250.223131] Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 41 56 48 8b 14 dd a0 4e 01 9f 48 89 ee 48 c7 c7 20 46 01 9f e8 cb 84d
[  250.225805] RSP: 0018:ffff888015ea7c08 EFLAGS: 00010286
[  250.226608] RAX: 0000000000000000 RBX: 0000000000000005 RCX: ffffffff9be93a95
[  250.227708] RDX: 1ffff1100d945138 RSI: 0000000000000008 RDI: ffff88806ca289c0
[  250.228993] RBP: ffffffff9f014a00 R08: 0000000000000001 R09: ffffed1002bd4f39
[  250.230043] R10: ffff888015ea79cf R11: 0000000000000001 R12: 0000000000000001
[  250.231185] R13: ffffffff9eea0520 R14: 0000000000000000 R15: ffff888015ea7cc8
[  250.232454] FS:  00007f3208f01540(0000) GS:ffff8880caf5a000(0000) knlGS:0000000000000000
[  250.233851] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  250.234856] CR2: 00007f32090a7421 CR3: 0000000004d63000 CR4: 00000000000006f0
[  250.236117] Call Trace:
[  250.236599]  <TASK>
[  250.236967]  ? trace_irq_enable.constprop.0+0xd4/0x130
[  250.237920]  debug_object_assert_init+0x1f6/0x310
[  250.238762]  ? __pfx_debug_object_assert_init+0x10/0x10
[  250.239658]  ? __lock_acquire+0xdea/0x1c70
[  250.240369]  __try_to_del_timer_sync+0x69/0x140
[  250.241172]  ? __pfx___try_to_del_timer_sync+0x10/0x10
[  250.242058]  ? __timer_delete_sync+0xc6/0x120
[  250.242842]  ? lock_acquire+0x30/0x80
[  250.243474]  ? __timer_delete_sync+0xc6/0x120
[  250.244262]  __timer_delete_sync+0x98/0x120
[  250.245015]  HFC_cleanup+0x10/0x20 [hfcpci]
[  250.245704]  __do_sys_delete_module+0x348/0x510
[  250.246461]  ? __pfx___do_sys_delete_module+0x10/0x10
[  250.247338]  do_syscall_64+0xc1/0x360
[  250.247924]  entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fix this by initializing hfc_tl timer with DEFINE_TIMER macro.
Also, use mod_timer instead of manual timeout update.

Fixes: 87c5fa1 ("mISDN: Add different different timer settings for hfc-pci")
Fixes: 175302f ("mISDN: hfcpci: Fix use-after-free bug in hfcpci_softirq")
Signed-off-by: Vladimir Riabchun <[email protected]>
Link: https://patch.msgid.link/aKiy2D_LiWpQ5kXq@vova-pc
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 31, 2025
If preparing a write bio fails then blk_zone_wplug_bio_work() calls
bio_endio() with zwplug->lock held. If a device mapper driver is stacked
on top of the zoned block device then this results in nested locking of
zwplug->lock. The resulting lockdep complaint is a false positive
because this is nested locking and not recursive locking. Suppress this
false positive by calling blk_zone_wplug_bio_io_error() without holding
zwplug->lock. This is safe because no code in
blk_zone_wplug_bio_io_error() depends on zwplug->lock being held. This
patch suppresses the following lockdep complaint:

WARNING: possible recursive locking detected
--------------------------------------------
kworker/3:0H/46 is trying to acquire lock:
ffffff882968b830 (&zwplug->lock){-...}-{2:2}, at: blk_zone_write_plug_bio_endio+0x64/0x1f0

but task is already holding lock:
ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&zwplug->lock);
  lock(&zwplug->lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by kworker/3:0H/46:
 #0: ffffff8809486758 ((wq_completion)sdd_zwplugs){+.+.}-{0:0}, at: process_one_work+0x1bc/0x65c
 #1: ffffffc085de3d70 ((work_completion)(&zwplug->bio_work)){+.+.}-{0:0}, at: process_one_work+0x1e4/0x65c
 #2: ffffff88315bc230 (&zwplug->lock){-...}-{2:2}, at: blk_zone_wplug_bio_work+0x8c/0x48c

stack backtrace:
CPU: 3 UID: 0 PID: 46 Comm: kworker/3:0H Tainted: G        W  OE      6.12.38-android16-5-maybe-dirty-4k #1 8b362b6f76e3645a58cd27d86982bce10d150025
Tainted: [W]=WARN, [O]=OOT_MODULE, [E]=UNSIGNED_MODULE
Hardware name: Spacecraft board based on MALIBU (DT)
Workqueue: sdd_zwplugs blk_zone_wplug_bio_work
Call trace:
 dump_backtrace+0xfc/0x17c
 show_stack+0x18/0x28
 dump_stack_lvl+0x40/0xa0
 dump_stack+0x18/0x24
 print_deadlock_bug+0x38c/0x398
 __lock_acquire+0x13e8/0x2e1c
 lock_acquire+0x134/0x2b4
 _raw_spin_lock_irqsave+0x5c/0x80
 blk_zone_write_plug_bio_endio+0x64/0x1f0
 bio_endio+0x9c/0x240
 __dm_io_complete+0x214/0x260
 clone_endio+0xe8/0x214
 bio_endio+0x218/0x240
 blk_zone_wplug_bio_work+0x204/0x48c
 process_one_work+0x26c/0x65c
 worker_thread+0x33c/0x498
 kthread+0x110/0x134
 ret_from_fork+0x10/0x20

Cc: [email protected]
Cc: Damien Le Moal <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Fixes: dd291d7 ("block: Introduce zone write plugging")
Signed-off-by: Bart Van Assche <[email protected]>
Reviewed-by: Damien Le Moal <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jens Axboe <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Aug 31, 2025
…ux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 changes for 6.17, take #2

 - Correctly handle 'invariant' system registers for protected VMs

 - Improved handling of VNCR data aborts, including external aborts

 - Fixes for handling of FEAT_RAS for NV guests, providing a sane
   fault context during SEA injection and preventing the use of
   RASv1p1 fault injection hardware

 - Ensure that page table destruction when a VM is destroyed gives an
   opportunity to reschedule

 - Large fix to KVM's infrastructure for managing guest context loaded
   on the CPU, addressing issues where the output of AT emulation
   doesn't get reflected to the guest

 - Fix AT S12 emulation to actually perform stage-2 translation when
   necessary

 - Avoid attempting vLPI irqbypass when GICv4 has been explicitly
   disabled for a VM

 - Minor KVM + selftest fixes
jwrdegoede pushed a commit that referenced this pull request Sep 10, 2025
In gicv5_irs_of_init_affinity() a WARN_ON() is triggered if:

 1) a phandle in the "cpus" property does not correspond to a valid OF
    node
 2  a CPU logical id does not exist for a given OF cpu_node

#1 is a firmware bug and should be reported as such but does not warrant a
   WARN_ON() backtrace.

#2 is not necessarily an error condition (eg a kernel can be booted with
   nr_cpus=X limiting the number of cores artificially) and therefore there
   is no reason to clutter the kernel log with WARN_ON() output when the
   condition is hit.

Rework the IRS affinity parsing code to remove undue WARN_ON()s thus
making it less noisy.

Signed-off-by: Lorenzo Pieralisi <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/[email protected]
jwrdegoede pushed a commit that referenced this pull request Sep 10, 2025
When the "proxy" option is enabled on a VXLAN device, the device will
suppress ARP requests and IPv6 Neighbor Solicitation messages if it is
able to reply on behalf of the remote host. That is, if a matching and
valid neighbor entry is configured on the VXLAN device whose MAC address
is not behind the "any" remote (0.0.0.0 / ::).

The code currently assumes that the FDB entry for the neighbor's MAC
address points to a valid remote destination, but this is incorrect if
the entry is associated with an FDB nexthop group. This can result in a
NPD [1][3] which can be reproduced using [2][4].

Fix by checking that the remote destination exists before dereferencing
it.

[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
CPU: 4 UID: 0 PID: 365 Comm: arping Not tainted 6.17.0-rc2-virtme-g2a89cb21162c #2 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.17.0-4.fc41 04/01/2014
RIP: 0010:vxlan_xmit+0xb58/0x15f0
[...]
Call Trace:
 <TASK>
 dev_hard_start_xmit+0x5d/0x1c0
 __dev_queue_xmit+0x246/0xfd0
 packet_sendmsg+0x113a/0x1850
 __sock_sendmsg+0x38/0x70
 __sys_sendto+0x126/0x180
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0xa4/0x260
 entry_SYSCALL_64_after_hwframe+0x4b/0x53

[2]
 #!/bin/bash

 ip address add 192.0.2.1/32 dev lo

 ip nexthop add id 1 via 192.0.2.2 fdb
 ip nexthop add id 10 group 1 fdb

 ip link add name vx0 up type vxlan id 10010 local 192.0.2.1 dstport 4789 proxy

 ip neigh add 192.0.2.3 lladdr 00:11:22:33:44:55 nud perm dev vx0

 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10

 arping -b -c 1 -s 192.0.2.1 -I vx0 192.0.2.3

[3]
BUG: kernel NULL pointer dereference, address: 0000000000000000
[...]
CPU: 13 UID: 0 PID: 372 Comm: ndisc6 Not tainted 6.17.0-rc2-virtmne-g6ee90cb26014 #3 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1v996), BIOS 1.17.0-4.fc41 04/01/2x014
RIP: 0010:vxlan_xmit+0x803/0x1600
[...]
Call Trace:
 <TASK>
 dev_hard_start_xmit+0x5d/0x1c0
 __dev_queue_xmit+0x246/0xfd0
 ip6_finish_output2+0x210/0x6c0
 ip6_finish_output+0x1af/0x2b0
 ip6_mr_output+0x92/0x3e0
 ip6_send_skb+0x30/0x90
 rawv6_sendmsg+0xe6e/0x12e0
 __sock_sendmsg+0x38/0x70
 __sys_sendto+0x126/0x180
 __x64_sys_sendto+0x24/0x30
 do_syscall_64+0xa4/0x260
 entry_SYSCALL_64_after_hwframe+0x4b/0x53
RIP: 0033:0x7f383422ec77

[4]
 #!/bin/bash

 ip address add 2001:db8:1::1/128 dev lo

 ip nexthop add id 1 via 2001:db8:1::1 fdb
 ip nexthop add id 10 group 1 fdb

 ip link add name vx0 up type vxlan id 10010 local 2001:db8:1::1 dstport 4789 proxy

 ip neigh add 2001:db8:1::3 lladdr 00:11:22:33:44:55 nud perm dev vx0

 bridge fdb add 00:11:22:33:44:55 dev vx0 self static nhid 10

 ndisc6 -r 1 -s 2001:db8:1::1 -w 1 2001:db8:1::3 vx0

Fixes: 1274e1c ("vxlan: ecmp support for mac fdb entries")
Reviewed-by: Petr Machata <[email protected]>
Signed-off-by: Ido Schimmel <[email protected]>
Reviewed-by: Nikolay Aleksandrov <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 10, 2025
Ido Schimmel says:

====================
vxlan: Fix NPDs when using nexthop objects

With FDB nexthop groups, VXLAN FDB entries do not necessarily point to
a remote destination but rather to an FDB nexthop group. This means that
first_remote_{rcu,rtnl}() can return NULL and a few places in the driver
were not ready for that, resulting in NULL pointer dereferences.
Patches #1-#2 fix these NPDs.

Note that vxlan_fdb_find_uc() still dereferences the remote returned by
first_remote_rcu() without checking that it is not NULL, but this
function is only invoked by a single driver which vetoes the creation of
FDB nexthop groups. I will patch this in net-next to make the code less
fragile.

Patch #3 adds a selftests which exercises these code paths and tests
basic Tx functionality with FDB nexthop groups. I verified that the test
crashes the kernel without the first two patches.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 10, 2025
When transmitting a PTP frame which is timestamp using 2 step, the
following warning appears if CONFIG_PROVE_LOCKING is enabled:
=============================
[ BUG: Invalid wait context ]
6.17.0-rc1-00326-ge6160462704e torvalds#427 Not tainted
-----------------------------
ptp4l/119 is trying to lock:
c2a44ed4 (&vsc8531->ts_lock){+.+.}-{3:3}, at: vsc85xx_txtstamp+0x50/0xac
other info that might help us debug this:
context-{4:4}
4 locks held by ptp4l/119:
 #0: c145f068 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x58/0x1440
 #1: c29df974 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x5c4/0x1440
 #2: c2aaaad0 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x108/0x350
 #3: c2aac170 (&lan966x->tx_lock){+.-.}-{2:2}, at: lan966x_port_xmit+0xd0/0x350
stack backtrace:
CPU: 0 UID: 0 PID: 119 Comm: ptp4l Not tainted 6.17.0-rc1-00326-ge6160462704e torvalds#427 NONE
Hardware name: Generic DT based system
Call trace:
 unwind_backtrace from show_stack+0x10/0x14
 show_stack from dump_stack_lvl+0x7c/0xac
 dump_stack_lvl from __lock_acquire+0x8e8/0x29dc
 __lock_acquire from lock_acquire+0x108/0x38c
 lock_acquire from __mutex_lock+0xb0/0xe78
 __mutex_lock from mutex_lock_nested+0x1c/0x24
 mutex_lock_nested from vsc85xx_txtstamp+0x50/0xac
 vsc85xx_txtstamp from lan966x_fdma_xmit+0xd8/0x3a8
 lan966x_fdma_xmit from lan966x_port_xmit+0x1bc/0x350
 lan966x_port_xmit from dev_hard_start_xmit+0xc8/0x2c0
 dev_hard_start_xmit from sch_direct_xmit+0x8c/0x350
 sch_direct_xmit from __dev_queue_xmit+0x680/0x1440
 __dev_queue_xmit from packet_sendmsg+0xfa4/0x1568
 packet_sendmsg from __sys_sendto+0x110/0x19c
 __sys_sendto from sys_send+0x18/0x20
 sys_send from ret_fast_syscall+0x0/0x1c
Exception stack(0xf0b05fa8 to 0xf0b05ff0)
5fa0:                   00000001 0000000 0000000 0004b47a 0000003a 00000000
5fc0: 00000001 0000000 00000000 00000121 0004af58 00044874 00000000 00000000
5fe0: 00000001 bee9d420 00025a10 b6e75c7c

So, instead of using the ts_lock for tx_queue, use the spinlock that
skb_buff_head has.

Reviewed-by: Vadim Fedorenko <[email protected]>
Fixes: 7d272e6 ("net: phy: mscc: timestamping and PHC support")
Signed-off-by: Horatiu Vultur <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 10, 2025
The commit ced17ee ("Revert "virtio: reject shm region if length is zero"")
exposes the following DAX page fault bug (this fix the failure that getting shm
region alway returns false because of zero length):

The commit 21aa65b ("mm: remove callers of pfn_t functionality") handles
the DAX physical page address incorrectly: the removed macro 'phys_to_pfn_t()'
should be replaced with 'PHYS_PFN()'.

[    1.390321] BUG: unable to handle page fault for address: ffffd3fb40000008
[    1.390875] #PF: supervisor read access in kernel mode
[    1.391257] #PF: error_code(0x0000) - not-present page
[    1.391509] PGD 0 P4D 0
[    1.391626] Oops: Oops: 0000 [#1] SMP NOPTI
[    1.391806] CPU: 6 UID: 1000 PID: 162 Comm: weston Not tainted 6.17.0-rc3-WSL2-STABLE #2 PREEMPT(none)
[    1.392361] RIP: 0010:dax_to_folio+0x14/0x60
[    1.392653] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff
[    1.393727] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086
[    1.394003] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000
[    1.394524] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000
[    1.394967] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000
[    1.395400] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000
[    1.395806] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000
[    1.396268] FS:  000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000
[    1.396715] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.397100] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0
[    1.397518] Call Trace:
[    1.397663]  <TASK>
[    1.397900]  dax_insert_entry+0x13b/0x390
[    1.398179]  dax_fault_iter+0x2a5/0x6c0
[    1.398443]  dax_iomap_pte_fault+0x193/0x3c0
[    1.398750]  __fuse_dax_fault+0x8b/0x270
[    1.398997]  ? vm_mmap_pgoff+0x161/0x210
[    1.399175]  __do_fault+0x30/0x180
[    1.399360]  do_fault+0xc4/0x550
[    1.399547]  __handle_mm_fault+0x8e3/0xf50
[    1.399731]  ? do_syscall_64+0x72/0x1e0
[    1.399958]  handle_mm_fault+0x192/0x2f0
[    1.400204]  do_user_addr_fault+0x20e/0x700
[    1.400418]  exc_page_fault+0x66/0x150
[    1.400602]  asm_exc_page_fault+0x26/0x30
[    1.400831] RIP: 0033:0x72596d1bf703
[    1.401076] Code: 31 f6 45 31 e4 48 8d 15 b3 73 00 00 e8 06 03 00 00 8b 83 68 01 00 00 e9 8e fa ff ff 0f 1f 00 48 8b 44 24 08 4c 89 ee 48 89 df <c7> 00 21 43 34 12 e8 72 09 00 00 e9 6a fa ff ff 0f 1f 44 00 00 e8
[    1.402172] RSP: 002b:00007ffc350f6dc0 EFLAGS: 00010202
[    1.402488] RAX: 0000725970e94000 RBX: 00005b7c642c2560 RCX: 0000725970d359a7
[    1.402898] RDX: 0000000000000003 RSI: 00007ffc350f6dc0 RDI: 00005b7c642c2560
[    1.403284] RBP: 00007ffc350f6e90 R08: 000000000000000d R09: 0000000000000000
[    1.403634] R10: 00007ffc350f6dd8 R11: 0000000000000246 R12: 0000000000000001
[    1.404078] R13: 00007ffc350f6dc0 R14: 0000725970e29ce0 R15: 0000000000000003
[    1.404450]  </TASK>
[    1.404570] Modules linked in:
[    1.404821] CR2: ffffd3fb40000008
[    1.405029] ---[ end trace 0000000000000000 ]---
[    1.405323] RIP: 0010:dax_to_folio+0x14/0x60
[    1.405556] Code: 52 c9 c3 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 48 c1 ef 05 48 c1 e7 06 48 03 3d 34 b5 31 01 <48> 8b 57 08 48 89 f8 f6 c2 01 75 2b 66 90 c3 cc cc cc cc f7 c7 ff
[    1.406639] RSP: 0000:ffffaf7d04407aa8 EFLAGS: 00010086
[    1.406910] RAX: 000000a000000000 RBX: ffffaf7d04407bb0 RCX: 0000000000000000
[    1.407379] RDX: ffffd17b40000008 RSI: 0000000000000083 RDI: ffffd3fb40000000
[    1.407800] RBP: 0000000000000011 R08: 000000a000000000 R09: 0000000000000000
[    1.408246] R10: 0000000000001000 R11: ffffaf7d04407c10 R12: 0000000000000000
[    1.408666] R13: ffffa020557be9c0 R14: 0000014000000001 R15: 0000725970e94000
[    1.409170] FS:  000072596d6d2ec0(0000) GS:ffffa0222dc59000(0000) knlGS:0000000000000000
[    1.409608] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.409977] CR2: ffffd3fb40000008 CR3: 000000011579c005 CR4: 0000000000372ef0
[    1.410437] Kernel panic - not syncing: Fatal exception
[    1.410857] Kernel Offset: 0xc000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

Fixes: 21aa65b ("mm: remove callers of pfn_t functionality")
Signed-off-by: Haiyue Wang <[email protected]>
Link: https://lore.kernel.org/[email protected]
Acked-by: David Hildenbrand <[email protected]>
Reviewed-by: Miklos Szeredi <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 20, 2025
Problem description
===================

Lockdep reports a possible circular locking dependency (AB/BA) between
&pl->state_mutex and &phy->lock, as follows.

phylink_resolve() // acquires &pl->state_mutex
-> phylink_major_config()
   -> phy_config_inband() // acquires &pl->phydev->lock

whereas all the other call sites where &pl->state_mutex and
&pl->phydev->lock have the locking scheme reversed. Everywhere else,
&pl->phydev->lock is acquired at the top level, and &pl->state_mutex at
the lower level. A clear example is phylink_bringup_phy().

The outlier is the newly introduced phy_config_inband() and the existing
lock order is the correct one. To understand why it cannot be the other
way around, it is sufficient to consider phylink_phy_change(), phylink's
callback from the PHY device's phy->phy_link_change() virtual method,
invoked by the PHY state machine.

phy_link_up() and phy_link_down(), the (indirect) callers of
phylink_phy_change(), are called with &phydev->lock acquired.
Then phylink_phy_change() acquires its own &pl->state_mutex, to
serialize changes made to its pl->phy_state and pl->link_config.
So all other instances of &pl->state_mutex and &phydev->lock must be
consistent with this order.

Problem impact
==============

I think the kernel runs a serious deadlock risk if an existing
phylink_resolve() thread, which results in a phy_config_inband() call,
is concurrent with a phy_link_up() or phy_link_down() call, which will
deadlock on &pl->state_mutex in phylink_phy_change(). Practically
speaking, the impact may be limited by the slow speed of the medium
auto-negotiation protocol, which makes it unlikely for the current state
to still be unresolved when a new one is detected, but I think the
problem is there. Nonetheless, the problem was discovered using lockdep.

Proposed solution
=================

Practically speaking, the phy_config_inband() requirement of having
phydev->lock acquired must transfer to the caller (phylink is the only
caller). There, it must bubble up until immediately before
&pl->state_mutex is acquired, for the cases where that takes place.

Solution details, considerations, notes
=======================================

This is the phy_config_inband() call graph:

                          sfp_upstream_ops :: connect_phy()
                          |
                          v
                          phylink_sfp_connect_phy()
                          |
                          v
                          phylink_sfp_config_phy()
                          |
                          |   sfp_upstream_ops :: module_insert()
                          |   |
                          |   v
                          |   phylink_sfp_module_insert()
                          |   |
                          |   |   sfp_upstream_ops :: module_start()
                          |   |   |
                          |   |   v
                          |   |   phylink_sfp_module_start()
                          |   |   |
                          |   v   v
                          |   phylink_sfp_config_optical()
 phylink_start()          |   |
   |   phylink_resume()   v   v
   |   |  phylink_sfp_set_config()
   |   |  |
   v   v  v
 phylink_mac_initial_config()
   |   phylink_resolve()
   |   |  phylink_ethtool_ksettings_set()
   v   v  v
   phylink_major_config()
            |
            v
    phy_config_inband()

phylink_major_config() caller #1, phylink_mac_initial_config(), does not
acquire &pl->state_mutex nor do its callers. It must acquire
&pl->phydev->lock prior to calling phylink_major_config().

phylink_major_config() caller #2, phylink_resolve() acquires
&pl->state_mutex, thus also needs to acquire &pl->phydev->lock.

phylink_major_config() caller #3, phylink_ethtool_ksettings_set(), is
completely uninteresting, because it only calls phylink_major_config()
if pl->phydev is NULL (otherwise it calls phy_ethtool_ksettings_set()).
We need to change nothing there.

Other solutions
===============

The lock inversion between &pl->state_mutex and &pl->phydev->lock has
occurred at least once before, as seen in commit c718af2 ("net:
phylink: fix ethtool -A with attached PHYs"). The solution there was to
simply not call phy_set_asym_pause() under the &pl->state_mutex. That
cannot be extended to our case though, where the phy_config_inband()
call is much deeper inside the &pl->state_mutex section.

Fixes: 5fd0f1a ("net: phylink: add negotiation of in-band capabilities")
Signed-off-by: Vladimir Oltean <[email protected]>
Reviewed-by: Russell King (Oracle) <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 20, 2025
5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing
"ranges"") simplified code by using the for_each_of_range() iterator, but
it broke PCI enumeration on Turris Omnia (and probably other mvebu
targets).

Issue #1:

To determine range.flags, of_pci_range_parser_one() uses bus->get_flags(),
which resolves to of_bus_pci_get_flags(), which already returns an
IORESOURCE bit field, and NOT the original flags from the "ranges"
resource.

Then mvebu_get_tgt_attr() attempts the very same conversion again.  Remove
the misinterpretation of range.flags in mvebu_get_tgt_attr(), to restore
the intended behavior.

Issue #2:

The driver needs target and attributes, which are encoded in the raw
address values of the "/soc/pcie/ranges" resource. According to
of_pci_range_parser_one(), the raw values are stored in range.bus_addr and
range.parent_bus_addr, respectively. range.cpu_addr is a translated version
of range.parent_bus_addr, and not relevant here.

Use the correct range structure member, to extract target and attributes.
This restores the intended behavior.

Fixes: 5da3d94 ("PCI: mvebu: Use for_each_of_range() iterator for parsing "ranges"")
Reported-by: Jan Palus <[email protected]>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=220479
Signed-off-by: Klaus Kudielka <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Tested-by: Tony Dinh <[email protected]>
Tested-by: Jan Palus <[email protected]>
Link: https://patch.msgid.link/[email protected]
jwrdegoede pushed a commit that referenced this pull request Sep 20, 2025
syzkaller has caught us red-handed once more, this time nesting regular
spinlocks behind raw spinlocks:

  =============================
  [ BUG: Invalid wait context ]
  6.16.0-rc3-syzkaller-g7b8346bd9fce #0 Not tainted
  -----------------------------
  syz.0.29/3743 is trying to lock:
  a3ff80008e2e9e18 (&xa->xa_lock#20){....}-{3:3}, at: vgic_put_irq+0xb4/0x190 arch/arm64/kvm/vgic/vgic.c:137
  other info that might help us debug this:
  context-{5:5}
  3 locks held by syz.0.29/3743:
   #0: a3ff80008e2e90a8 (&kvm->slots_lock){+.+.}-{4:4}, at: kvm_vgic_destroy+0x50/0x624 arch/arm64/kvm/vgic/vgic-init.c:499
   #1: a3ff80008e2e9fa0 (&kvm->arch.config_lock){+.+.}-{4:4}, at: kvm_vgic_destroy+0x5c/0x624 arch/arm64/kvm/vgic/vgic-init.c:500
   #2: 58f0000021be1428 (&vgic_cpu->ap_list_lock){....}-{2:2}, at: vgic_flush_pending_lpis+0x3c/0x31c arch/arm64/kvm/vgic/vgic.c:150
  stack backtrace:
  CPU: 0 UID: 0 PID: 3743 Comm: syz.0.29 Not tainted 6.16.0-rc3-syzkaller-g7b8346bd9fce #0 PREEMPT
  Hardware name: linux,dummy-virt (DT)
  Call trace:
   show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:466 (C)
   __dump_stack+0x30/0x40 lib/dump_stack.c:94
   dump_stack_lvl+0xd8/0x12c lib/dump_stack.c:120
   dump_stack+0x1c/0x28 lib/dump_stack.c:129
   print_lock_invalid_wait_context kernel/locking/lockdep.c:4833 [inline]
   check_wait_context kernel/locking/lockdep.c:4905 [inline]
   __lock_acquire+0x978/0x299c kernel/locking/lockdep.c:5190
   lock_acquire+0x14c/0x2e0 kernel/locking/lockdep.c:5871
   __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
   _raw_spin_lock_irqsave+0x5c/0x7c kernel/locking/spinlock.c:162
   vgic_put_irq+0xb4/0x190 arch/arm64/kvm/vgic/vgic.c:137
   vgic_flush_pending_lpis+0x24c/0x31c arch/arm64/kvm/vgic/vgic.c:158
   __kvm_vgic_vcpu_destroy+0x44/0x500 arch/arm64/kvm/vgic/vgic-init.c:455
   kvm_vgic_destroy+0x100/0x624 arch/arm64/kvm/vgic/vgic-init.c:505
   kvm_arch_destroy_vm+0x80/0x138 arch/arm64/kvm/arm.c:244
   kvm_destroy_vm virt/kvm/kvm_main.c:1308 [inline]
   kvm_put_kvm+0x800/0xff8 virt/kvm/kvm_main.c:1344
   kvm_vm_release+0x58/0x78 virt/kvm/kvm_main.c:1367
   __fput+0x4ac/0x980 fs/file_table.c:465
   ____fput+0x20/0x58 fs/file_table.c:493
   task_work_run+0x1bc/0x254 kernel/task_work.c:227
   resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
   do_notify_resume+0x1b4/0x270 arch/arm64/kernel/entry-common.c:151
   exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:169 [inline]
   exit_to_user_mode arch/arm64/kernel/entry-common.c:178 [inline]
   el0_svc+0xb4/0x160 arch/arm64/kernel/entry-common.c:768
   el0t_64_sync_handler+0x78/0x108 arch/arm64/kernel/entry-common.c:786
   el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600

This is of course no good, but is at odds with how LPI refcounts are
managed. Solve the locking mess by deferring the release of unreferenced
LPIs after the ap_list_lock is released. Mark these to-be-released LPIs
specially to avoid racing with vgic_put_irq() and causing a double-free.

Since references can only be taken on LPIs with a nonzero refcount,
extending the lifetime of freed LPIs is still safe.

Reviewed-by: Marc Zyngier <[email protected]>
Reported-by: [email protected]
Closes: https://lore.kernel.org/kvmarm/[email protected]/
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Oliver Upton <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Sep 20, 2025
…ostcopy

When you run a KVM guest with vhost-net and migrate that guest to
another host, and you immediately enable postcopy after starting the
migration, there is a big chance that the network connection of the
guest won't work anymore on the destination side after the migration.

With a debug kernel v6.16.0, there is also a call trace that looks
like this:

 FAULT_FLAG_ALLOW_RETRY missing 881
 CPU: 6 UID: 0 PID: 549 Comm: kworker/6:2 Kdump: loaded Not tainted 6.16.0 linux-sunxi#56 NONE
 Hardware name: IBM 3931 LA1 400 (LPAR)
 Workqueue: events irqfd_inject [kvm]
 Call Trace:
  [<00003173cbecc634>] dump_stack_lvl+0x104/0x168
  [<00003173cca69588>] handle_userfault+0xde8/0x1310
  [<00003173cc756f0c>] handle_pte_fault+0x4fc/0x760
  [<00003173cc759212>] __handle_mm_fault+0x452/0xa00
  [<00003173cc7599ba>] handle_mm_fault+0x1fa/0x6a0
  [<00003173cc73409a>] __get_user_pages+0x4aa/0xba0
  [<00003173cc7349e8>] get_user_pages_remote+0x258/0x770
  [<000031734be6f052>] get_map_page+0xe2/0x190 [kvm]
  [<000031734be6f910>] adapter_indicators_set+0x50/0x4a0 [kvm]
  [<000031734be7f674>] set_adapter_int+0xc4/0x170 [kvm]
  [<000031734be2f268>] kvm_set_irq+0x228/0x3f0 [kvm]
  [<000031734be27000>] irqfd_inject+0xd0/0x150 [kvm]
  [<00003173cc00c9ec>] process_one_work+0x87c/0x1490
  [<00003173cc00dda6>] worker_thread+0x7a6/0x1010
  [<00003173cc02dc36>] kthread+0x3b6/0x710
  [<00003173cbed2f0c>] __ret_from_fork+0xdc/0x7f0
  [<00003173cdd737ca>] ret_from_fork+0xa/0x30
 3 locks held by kworker/6:2/549:
  #0: 00000000800bc958 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7ee/0x1490
  #1: 000030f3d527fbd0 ((work_completion)(&irqfd->inject)){+.+.}-{0:0}, at: process_one_work+0x81c/0x1490
  #2: 00000000f99862b0 (&mm->mmap_lock){++++}-{3:3}, at: get_map_page+0xa8/0x190 [kvm]

The "FAULT_FLAG_ALLOW_RETRY missing" indicates that handle_userfaultfd()
saw a page fault request without ALLOW_RETRY flag set, hence userfaultfd
cannot remotely resolve it (because the caller was asking for an immediate
resolution, aka, FAULT_FLAG_NOWAIT, while remote faults can take time).
With that, get_map_page() failed and the irq was lost.

We should not be strictly in an atomic environment here and the worker
should be sleepable (the call is done during an ioctl from userspace),
so we can allow adapter_indicators_set() to just sleep waiting for the
remote fault instead.

Link: https://issues.redhat.com/browse/RHEL-42486
Signed-off-by: Peter Xu <[email protected]>
[thuth: Assembled patch description and fixed some cosmetical issues]
Signed-off-by: Thomas Huth <[email protected]>
Reviewed-by: Claudio Imbrenda <[email protected]>
Acked-by: Janosch Frank <[email protected]>
Fixes: f654706 ("KVM: s390/interrupt: do not pin adapter interrupt pages")
[frankja: Added fixes tag]
Signed-off-by: Janosch Frank <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 8, 2025
This attemps to fix possible UAFs caused by struct mgmt_pending being
freed while still being processed like in the following trace, in order
to fix mgmt_pending_valid is introduce and use to check if the
mgmt_pending hasn't been removed from the pending list, on the complete
callbacks it is used to check and in addtion remove the cmd from the list
while holding mgmt_pending_lock to avoid TOCTOU problems since if the cmd
is left on the list it can still be accessed and freed.

BUG: KASAN: slab-use-after-free in mgmt_add_adv_patterns_monitor_sync+0x35/0x50 net/bluetooth/mgmt.c:5223
Read of size 8 at addr ffff8880709d4dc0 by task kworker/u11:0/55

CPU: 0 UID: 0 PID: 55 Comm: kworker/u11:0 Not tainted 6.16.4 #2 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 mgmt_add_adv_patterns_monitor_sync+0x35/0x50 net/bluetooth/mgmt.c:5223
 hci_cmd_sync_work+0x210/0x3a0 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x711/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 home/kwqcheii/source/fuzzing/kernel/kasan/linux-6.16.4/arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 12210:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __kmalloc_cache_noprof+0x230/0x3d0 mm/slub.c:4364
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 mgmt_pending_new+0x65/0x1e0 net/bluetooth/mgmt_util.c:269
 mgmt_pending_add+0x35/0x140 net/bluetooth/mgmt_util.c:296
 __add_adv_patterns_monitor+0x130/0x200 net/bluetooth/mgmt.c:5247
 add_adv_patterns_monitor+0x214/0x360 net/bluetooth/mgmt.c:5364
 hci_mgmt_cmd+0x9c9/0xef0 net/bluetooth/hci_sock.c:1719
 hci_sock_sendmsg+0x6ca/0xef0 net/bluetooth/hci_sock.c:1839
 sock_sendmsg_nosec net/socket.c:714 [inline]
 __sock_sendmsg+0x219/0x270 net/socket.c:729
 sock_write_iter+0x258/0x330 net/socket.c:1133
 new_sync_write fs/read_write.c:593 [inline]
 vfs_write+0x5c9/0xb30 fs/read_write.c:686
 ksys_write+0x145/0x250 fs/read_write.c:738
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 12221:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x62/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2381 [inline]
 slab_free mm/slub.c:4648 [inline]
 kfree+0x18e/0x440 mm/slub.c:4847
 mgmt_pending_free net/bluetooth/mgmt_util.c:311 [inline]
 mgmt_pending_foreach+0x30d/0x380 net/bluetooth/mgmt_util.c:257
 __mgmt_power_off+0x169/0x350 net/bluetooth/mgmt.c:9444
 hci_dev_close_sync+0x754/0x1330 net/bluetooth/hci_sync.c:5290
 hci_dev_do_close net/bluetooth/hci_core.c:501 [inline]
 hci_dev_close+0x108/0x200 net/bluetooth/hci_core.c:526
 sock_do_ioctl+0xd9/0x300 net/socket.c:1192
 sock_ioctl+0x576/0x790 net/socket.c:1313
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:893
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Fixes: cf75ad8 ("Bluetooth: hci_sync: Convert MGMT_SET_POWERED")
Fixes: 2bd1b23 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_DISCOVERABLE to use cmd_sync")
Fixes: f056a65 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_CONNECTABLE to use cmd_sync")
Fixes: 3244845 ("Bluetooth: hci_sync: Convert MGMT_OP_SSP")
Fixes: d81a494 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_LE")
Fixes: b338d91 ("Bluetooth: Implement support for Mesh")
Fixes: 6f6ff38 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_LOCAL_NAME")
Fixes: 71efbb0 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_PHY_CONFIGURATION")
Fixes: b747a83 ("Bluetooth: hci_sync: Refactor add Adv Monitor")
Fixes: abfeea4 ("Bluetooth: hci_sync: Convert MGMT_OP_START_DISCOVERY")
Fixes: 26ac4c5 ("Bluetooth: hci_sync: Convert MGMT_OP_SET_ADVERTISING")
Reported-by: cen zhang <[email protected]>
Signed-off-by: Luiz Augusto von Dentz <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 8, 2025
Ido Schimmel says:

====================
nexthop: Various fixes

Patch #1 fixes a NPD that was recently reported by syzbot.

Patch #2 fixes an issue in the existing FIB nexthop selftest.

Patch #3 extends the selftest with test cases for the bug that was fixed
in the first patch.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Oct 27, 2025
The original code causes a circular locking dependency found by lockdep.

======================================================
WARNING: possible circular locking dependency detected
6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 Tainted: G S   U
------------------------------------------------------
xe_fault_inject/5091 is trying to acquire lock:
ffff888156815688 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}, at: __flush_work+0x25d/0x660

but task is already holding lock:

ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #2 (&devcd->mutex){+.+.}-{3:3}:
       mutex_lock_nested+0x4e/0xc0
       devcd_data_write+0x27/0x90
       sysfs_kf_bin_write+0x80/0xf0
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
-> #1 (kn->active#236){++++}-{0:0}:
       kernfs_drain+0x1e2/0x200
       __kernfs_remove+0xae/0x400
       kernfs_remove_by_name_ns+0x5d/0xc0
       remove_files+0x54/0x70
       sysfs_remove_group+0x3d/0xa0
       sysfs_remove_groups+0x2e/0x60
       device_remove_attrs+0xc7/0x100
       device_del+0x15d/0x3b0
       devcd_del+0x19/0x30
       process_one_work+0x22b/0x6f0
       worker_thread+0x1e8/0x3d0
       kthread+0x11c/0x250
       ret_from_fork+0x26c/0x2e0
       ret_from_fork_asm+0x1a/0x30
-> #0 ((work_completion)(&(&devcd->del_wk)->work)){+.+.}-{0:0}:
       __lock_acquire+0x1661/0x2860
       lock_acquire+0xc4/0x2f0
       __flush_work+0x27a/0x660
       flush_delayed_work+0x5d/0xa0
       dev_coredump_put+0x63/0xa0
       xe_driver_devcoredump_fini+0x12/0x20 [xe]
       devm_action_release+0x12/0x30
       release_nodes+0x3a/0x120
       devres_release_all+0x8a/0xd0
       device_unbind_cleanup+0x12/0x80
       device_release_driver_internal+0x23a/0x280
       device_driver_detach+0x14/0x20
       unbind_store+0xaf/0xc0
       drv_attr_store+0x21/0x50
       sysfs_kf_write+0x4a/0x80
       kernfs_fop_write_iter+0x169/0x220
       vfs_write+0x293/0x560
       ksys_write+0x72/0xf0
       __x64_sys_write+0x19/0x30
       x64_sys_call+0x2bf/0x2660
       do_syscall_64+0x93/0xb60
       entry_SYSCALL_64_after_hwframe+0x76/0x7e
other info that might help us debug this:
Chain exists of: (work_completion)(&(&devcd->del_wk)->work) --> kn->active#236 --> &devcd->mutex
 Possible unsafe locking scenario:
       CPU0                    CPU1
       ----                    ----
  lock(&devcd->mutex);
                               lock(kn->active#236);
                               lock(&devcd->mutex);
  lock((work_completion)(&(&devcd->del_wk)->work));
 *** DEADLOCK ***
5 locks held by xe_fault_inject/5091:
 #0: ffff8881129f9488 (sb_writers#5){.+.+}-{0:0}, at: ksys_write+0x72/0xf0
 #1: ffff88810c755078 (&of->mutex#2){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x123/0x220
 #2: ffff8881054811a0 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0x55/0x280
 #3: ffff888156815620 (&devcd->mutex){+.+.}-{3:3}, at: dev_coredump_put+0x3f/0xa0
 #4: ffffffff8359e020 (rcu_read_lock){....}-{1:2}, at: __flush_work+0x72/0x660
stack backtrace:
CPU: 14 UID: 0 PID: 5091 Comm: xe_fault_inject Tainted: G S   U              6.16.0-rc6-lgci-xe-xe-pw-151626v3+ #1 PREEMPT_{RT,(lazy)}
Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER
Hardware name: Micro-Star International Co., Ltd. MS-7D25/PRO Z690-A DDR4(MS-7D25), BIOS 1.10 12/13/2021
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 dump_stack+0x10/0x20
 print_circular_bug+0x285/0x360
 check_noncircular+0x135/0x150
 ? register_lock_class+0x48/0x4a0
 __lock_acquire+0x1661/0x2860
 lock_acquire+0xc4/0x2f0
 ? __flush_work+0x25d/0x660
 ? mark_held_locks+0x46/0x90
 ? __flush_work+0x25d/0x660
 __flush_work+0x27a/0x660
 ? __flush_work+0x25d/0x660
 ? trace_hardirqs_on+0x1e/0xd0
 ? __pfx_wq_barrier_func+0x10/0x10
 flush_delayed_work+0x5d/0xa0
 dev_coredump_put+0x63/0xa0
 xe_driver_devcoredump_fini+0x12/0x20 [xe]
 devm_action_release+0x12/0x30
 release_nodes+0x3a/0x120
 devres_release_all+0x8a/0xd0
 device_unbind_cleanup+0x12/0x80
 device_release_driver_internal+0x23a/0x280
 ? bus_find_device+0xa8/0xe0
 device_driver_detach+0x14/0x20
 unbind_store+0xaf/0xc0
 drv_attr_store+0x21/0x50
 sysfs_kf_write+0x4a/0x80
 kernfs_fop_write_iter+0x169/0x220
 vfs_write+0x293/0x560
 ksys_write+0x72/0xf0
 __x64_sys_write+0x19/0x30
 x64_sys_call+0x2bf/0x2660
 do_syscall_64+0x93/0xb60
 ? __f_unlock_pos+0x15/0x20
 ? __x64_sys_getdents64+0x9b/0x130
 ? __pfx_filldir64+0x10/0x10
 ? do_syscall_64+0x1a2/0xb60
 ? clear_bhb_loop+0x30/0x80
 ? clear_bhb_loop+0x30/0x80
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x76e292edd574
Code: c7 00 16 00 00 00 b8 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 80 3d d5 ea 0e 00 00 74 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 c3 0f 1f 00 55 48 89 e5 48 83 ec 20 48 89
RSP: 002b:00007fffe247a828 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000076e292edd574
RDX: 000000000000000c RSI: 00006267f6306063 RDI: 000000000000000b
RBP: 000000000000000c R08: 000076e292fc4b20 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00006267f6306063
R13: 000000000000000b R14: 00006267e6859c00 R15: 000076e29322a000
 </TASK>
xe 0000:03:00.0: [drm] Xe device coredump has been deleted.

Fixes: 01daccf ("devcoredump : Serialize devcd_del work")
Cc: Mukesh Ojha <[email protected]>
Cc: Greg Kroah-Hartman <[email protected]>
Cc: Johannes Berg <[email protected]>
Cc: Rafael J. Wysocki <[email protected]>
Cc: Danilo Krummrich <[email protected]>
Cc: [email protected]
Cc: [email protected] # v6.1+
Signed-off-by: Maarten Lankhorst <[email protected]>
Cc: Matthew Brost <[email protected]>
Acked-by: Mukesh Ojha <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
Michael Chan says:

====================
bnxt_en: Bug fixes

Patches 1, 3, and 4 are bug fixes related to the FW log tracing driver
coredump feature recently added in 6.13.  Patch #1 adds the necessary
call to shutdown the FW logging DMA during PCI shutdown.  Patch #3 fixes
a possible null pointer derefernce when using early versions of the FW
with this feature.  Patch #4 adds the coredump header information
unconditionally to make it more robust.

Patch #2 fixes a possible memory leak during PTP shutdown.  Patch #5
eliminates a dmesg warning when doing devlink reload.
====================

Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
On completion of i915_vma_pin_ww(), a synchronous variant of
dma_fence_work_commit() is called.  When pinning a VMA to GGTT address
space on a Cherry View family processor, or on a Broxton generation SoC
with VTD enabled, i.e., when stop_machine() is then called from
intel_ggtt_bind_vma(), that can potentially lead to lock inversion among
reservation_ww and cpu_hotplug locks.

[86.861179] ======================================================
[86.861193] WARNING: possible circular locking dependency detected
[86.861209] 6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 Tainted: G     U
[86.861226] ------------------------------------------------------
[86.861238] i915_module_loa/1432 is trying to acquire lock:
[86.861252] ffffffff83489090 (cpu_hotplug_lock){++++}-{0:0}, at: stop_machine+0x1c/0x50
[86.861290]
but task is already holding lock:
[86.861303] ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.862233]
which lock already depends on the new lock.
[86.862251]
the existing dependency chain (in reverse order) is:
[86.862265]
-> #5 (reservation_ww_class_mutex){+.+.}-{3:3}:
[86.862292]        dma_resv_lockdep+0x19a/0x390
[86.862315]        do_one_initcall+0x60/0x3f0
[86.862334]        kernel_init_freeable+0x3cd/0x680
[86.862353]        kernel_init+0x1b/0x200
[86.862369]        ret_from_fork+0x47/0x70
[86.862383]        ret_from_fork_asm+0x1a/0x30
[86.862399]
-> #4 (reservation_ww_class_acquire){+.+.}-{0:0}:
[86.862425]        dma_resv_lockdep+0x178/0x390
[86.862440]        do_one_initcall+0x60/0x3f0
[86.862454]        kernel_init_freeable+0x3cd/0x680
[86.862470]        kernel_init+0x1b/0x200
[86.862482]        ret_from_fork+0x47/0x70
[86.862495]        ret_from_fork_asm+0x1a/0x30
[86.862509]
-> #3 (&mm->mmap_lock){++++}-{3:3}:
[86.862531]        down_read_killable+0x46/0x1e0
[86.862546]        lock_mm_and_find_vma+0xa2/0x280
[86.862561]        do_user_addr_fault+0x266/0x8e0
[86.862578]        exc_page_fault+0x8a/0x2f0
[86.862593]        asm_exc_page_fault+0x27/0x30
[86.862607]        filldir64+0xeb/0x180
[86.862620]        kernfs_fop_readdir+0x118/0x480
[86.862635]        iterate_dir+0xcf/0x2b0
[86.862648]        __x64_sys_getdents64+0x84/0x140
[86.862661]        x64_sys_call+0x1058/0x2660
[86.862675]        do_syscall_64+0x91/0xe90
[86.862689]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.862703]
-> #2 (&root->kernfs_rwsem){++++}-{3:3}:
[86.862725]        down_write+0x3e/0xf0
[86.862738]        kernfs_add_one+0x30/0x3c0
[86.862751]        kernfs_create_dir_ns+0x53/0xb0
[86.862765]        internal_create_group+0x134/0x4c0
[86.862779]        sysfs_create_group+0x13/0x20
[86.862792]        topology_add_dev+0x1d/0x30
[86.862806]        cpuhp_invoke_callback+0x4b5/0x850
[86.862822]        cpuhp_issue_call+0xbf/0x1f0
[86.862836]        __cpuhp_setup_state_cpuslocked+0x111/0x320
[86.862852]        __cpuhp_setup_state+0xb0/0x220
[86.862866]        topology_sysfs_init+0x30/0x50
[86.862879]        do_one_initcall+0x60/0x3f0
[86.862893]        kernel_init_freeable+0x3cd/0x680
[86.862908]        kernel_init+0x1b/0x200
[86.862921]        ret_from_fork+0x47/0x70
[86.862934]        ret_from_fork_asm+0x1a/0x30
[86.862947]
-> #1 (cpuhp_state_mutex){+.+.}-{3:3}:
[86.862969]        __mutex_lock+0xaa/0xed0
[86.862982]        mutex_lock_nested+0x1b/0x30
[86.862995]        __cpuhp_setup_state_cpuslocked+0x67/0x320
[86.863012]        __cpuhp_setup_state+0xb0/0x220
[86.863026]        page_alloc_init_cpuhp+0x2d/0x60
[86.863041]        mm_core_init+0x22/0x2d0
[86.863054]        start_kernel+0x576/0xbd0
[86.863068]        x86_64_start_reservations+0x18/0x30
[86.863084]        x86_64_start_kernel+0xbf/0x110
[86.863098]        common_startup_64+0x13e/0x141
[86.863114]
-> #0 (cpu_hotplug_lock){++++}-{0:0}:
[86.863135]        __lock_acquire+0x1635/0x2810
[86.863152]        lock_acquire+0xc4/0x2f0
[86.863166]        cpus_read_lock+0x41/0x100
[86.863180]        stop_machine+0x1c/0x50
[86.863194]        bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.863987]        intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.864735]        __vma_bind+0x55/0x70 [i915]
[86.865510]        fence_work+0x26/0xa0 [i915]
[86.866248]        fence_notify+0xa1/0x140 [i915]
[86.866983]        __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.867719]        i915_sw_fence_commit+0x39/0x60 [i915]
[86.868453]        i915_vma_pin_ww+0x462/0x1360 [i915]
[86.869228]        i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.870001]        initial_plane_vma+0x307/0x840 [i915]
[86.870774]        intel_initial_plane_config+0x33f/0x670 [i915]
[86.871546]        intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.872330]        i915_driver_probe+0x7fa/0xe80 [i915]
[86.873057]        i915_pci_probe+0xe6/0x220 [i915]
[86.873782]        local_pci_probe+0x47/0xb0
[86.873802]        pci_device_probe+0xf3/0x260
[86.873817]        really_probe+0xf1/0x3c0
[86.873833]        __driver_probe_device+0x8c/0x180
[86.873848]        driver_probe_device+0x24/0xd0
[86.873862]        __driver_attach+0x10f/0x220
[86.873876]        bus_for_each_dev+0x7f/0xe0
[86.873892]        driver_attach+0x1e/0x30
[86.873904]        bus_add_driver+0x151/0x290
[86.873917]        driver_register+0x5e/0x130
[86.873931]        __pci_register_driver+0x7d/0x90
[86.873945]        i915_pci_register_driver+0x23/0x30 [i915]
[86.874678]        i915_init+0x37/0x120 [i915]
[86.875347]        do_one_initcall+0x60/0x3f0
[86.875369]        do_init_module+0x97/0x2a0
[86.875385]        load_module+0x2c54/0x2d80
[86.875398]        init_module_from_file+0x96/0xe0
[86.875413]        idempotent_init_module+0x117/0x330
[86.875426]        __x64_sys_finit_module+0x77/0x100
[86.875440]        x64_sys_call+0x24de/0x2660
[86.875454]        do_syscall_64+0x91/0xe90
[86.875470]        entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.875486]
other info that might help us debug this:
[86.875502] Chain exists of:
  cpu_hotplug_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex
[86.875539]  Possible unsafe locking scenario:
[86.875552]        CPU0                    CPU1
[86.875563]        ----                    ----
[86.875573]   lock(reservation_ww_class_mutex);
[86.875588]                                lock(reservation_ww_class_acquire);
[86.875606]                                lock(reservation_ww_class_mutex);
[86.875624]   rlock(cpu_hotplug_lock);
[86.875637]
 *** DEADLOCK ***
[86.875650] 3 locks held by i915_module_loa/1432:
[86.875663]  #0: ffff888101f5c1b0 (&dev->mutex){....}-{3:3}, at: __driver_attach+0x104/0x220
[86.875699]  #1: ffffc90002e0b4a0 (reservation_ww_class_acquire){+.+.}-{0:0}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.876512]  #2: ffffc90002e0b4c8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: i915_vma_pin.constprop.0+0x39/0x1d0 [i915]
[86.877305]
stack backtrace:
[86.877326] CPU: 0 UID: 0 PID: 1432 Comm: i915_module_loa Tainted: G     U              6.15.0-rc5-CI_DRM_16515-gca0305cadc2d+ #1 PREEMPT(voluntary)
[86.877334] Tainted: [U]=USER
[86.877336] Hardware name:  /NUC5CPYB, BIOS PYBSWCEL.86A.0079.2020.0420.1316 04/20/2020
[86.877339] Call Trace:
[86.877344]  <TASK>
[86.877353]  dump_stack_lvl+0x91/0xf0
[86.877364]  dump_stack+0x10/0x20
[86.877369]  print_circular_bug+0x285/0x360
[86.877379]  check_noncircular+0x135/0x150
[86.877390]  __lock_acquire+0x1635/0x2810
[86.877403]  lock_acquire+0xc4/0x2f0
[86.877408]  ? stop_machine+0x1c/0x50
[86.877422]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878173]  cpus_read_lock+0x41/0x100
[86.878182]  ? stop_machine+0x1c/0x50
[86.878191]  ? __pfx_bxt_vtd_ggtt_insert_entries__cb+0x10/0x10 [i915]
[86.878916]  stop_machine+0x1c/0x50
[86.878927]  bxt_vtd_ggtt_insert_entries__BKL+0x3b/0x60 [i915]
[86.879652]  intel_ggtt_bind_vma+0x43/0x70 [i915]
[86.880375]  __vma_bind+0x55/0x70 [i915]
[86.881133]  fence_work+0x26/0xa0 [i915]
[86.881851]  fence_notify+0xa1/0x140 [i915]
[86.882566]  __i915_sw_fence_complete+0x8f/0x270 [i915]
[86.883286]  i915_sw_fence_commit+0x39/0x60 [i915]
[86.884003]  i915_vma_pin_ww+0x462/0x1360 [i915]
[86.884756]  ? i915_vma_pin.constprop.0+0x6c/0x1d0 [i915]
[86.885513]  i915_vma_pin.constprop.0+0x133/0x1d0 [i915]
[86.886281]  initial_plane_vma+0x307/0x840 [i915]
[86.887049]  intel_initial_plane_config+0x33f/0x670 [i915]
[86.887819]  intel_display_driver_probe_nogem+0x1c6/0x260 [i915]
[86.888587]  i915_driver_probe+0x7fa/0xe80 [i915]
[86.889293]  ? mutex_unlock+0x12/0x20
[86.889301]  ? drm_privacy_screen_get+0x171/0x190
[86.889308]  ? acpi_dev_found+0x66/0x80
[86.889321]  i915_pci_probe+0xe6/0x220 [i915]
[86.890038]  local_pci_probe+0x47/0xb0
[86.890049]  pci_device_probe+0xf3/0x260
[86.890058]  really_probe+0xf1/0x3c0
[86.890067]  __driver_probe_device+0x8c/0x180
[86.890072]  driver_probe_device+0x24/0xd0
[86.890078]  __driver_attach+0x10f/0x220
[86.890083]  ? __pfx___driver_attach+0x10/0x10
[86.890088]  bus_for_each_dev+0x7f/0xe0
[86.890097]  driver_attach+0x1e/0x30
[86.890101]  bus_add_driver+0x151/0x290
[86.890107]  driver_register+0x5e/0x130
[86.890113]  __pci_register_driver+0x7d/0x90
[86.890119]  i915_pci_register_driver+0x23/0x30 [i915]
[86.890833]  i915_init+0x37/0x120 [i915]
[86.891482]  ? __pfx_i915_init+0x10/0x10 [i915]
[86.892135]  do_one_initcall+0x60/0x3f0
[86.892145]  ? __kmalloc_cache_noprof+0x33f/0x470
[86.892157]  do_init_module+0x97/0x2a0
[86.892164]  load_module+0x2c54/0x2d80
[86.892168]  ? __kernel_read+0x15c/0x300
[86.892185]  ? kernel_read_file+0x2b1/0x320
[86.892195]  init_module_from_file+0x96/0xe0
[86.892199]  ? init_module_from_file+0x96/0xe0
[86.892211]  idempotent_init_module+0x117/0x330
[86.892224]  __x64_sys_finit_module+0x77/0x100
[86.892230]  x64_sys_call+0x24de/0x2660
[86.892236]  do_syscall_64+0x91/0xe90
[86.892243]  ? irqentry_exit+0x77/0xb0
[86.892249]  ? sysvec_apic_timer_interrupt+0x57/0xc0
[86.892256]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[86.892261] RIP: 0033:0x7303e1b2725d
[86.892271] Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8b bb 0d 00 f7 d8 64 89 01 48
[86.892276] RSP: 002b:00007ffddd1fdb38 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[86.892281] RAX: ffffffffffffffda RBX: 00005d771d88fd90 RCX: 00007303e1b2725d
[86.892285] RDX: 0000000000000000 RSI: 00005d771d893aa0 RDI: 000000000000000c
[86.892287] RBP: 00007ffddd1fdbf0 R08: 0000000000000040 R09: 00007ffddd1fdb80
[86.892289] R10: 00007303e1c03b20 R11: 0000000000000246 R12: 00005d771d893aa0
[86.892292] R13: 0000000000000000 R14: 00005d771d88f0d0 R15: 00005d771d895710
[86.892304]  </TASK>

Call asynchronous variant of dma_fence_work_commit() in that case.

v3: Provide more verbose in-line comment (Andi),
  - mention target environments in commit message.

Fixes: 7d1c261 ("drm/i915: Take reservation lock around i915_vma_pin.")
Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/14985
Cc: Andi Shyti <[email protected]>
Signed-off-by: Janusz Krzysztofik <[email protected]>
Reviewed-by: Sebastian Brzezinka <[email protected]>
Reviewed-by: Krzysztof Karas <[email protected]>
Acked-by: Andi Shyti <[email protected]>
Signed-off-by: Andi Shyti <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
(cherry picked from commit 648ef13)
Signed-off-by: Rodrigo Vivi <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
When a connector is connected but inactive (e.g., disabled by desktop
environments), pipe_ctx->stream_res.tg will be destroyed. Then, reading
odm_combine_segments causes kernel NULL pointer dereference.

 BUG: kernel NULL pointer dereference, address: 0000000000000000
 #PF: supervisor read access in kernel mode
 #PF: error_code(0x0000) - not-present page
 PGD 0 P4D 0
 Oops: Oops: 0000 [#1] SMP NOPTI
 CPU: 16 UID: 0 PID: 26474 Comm: cat Not tainted 6.17.0+ #2 PREEMPT(lazy)  e6a17af9ee6db7c63e9d90dbe5b28ccab67520c6
 Hardware name: LENOVO 21Q4/LNVNB161216, BIOS PXCN25WW 03/27/2025
 RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu]
 Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00>
 RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286
 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8
 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0
 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08
 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001
 FS:  00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0
 PKRU: 55555554
 Call Trace:
  <TASK>
  seq_read_iter+0x125/0x490
  ? __alloc_frozen_pages_noprof+0x18f/0x350
  seq_read+0x12c/0x170
  full_proxy_read+0x51/0x80
  vfs_read+0xbc/0x390
  ? __handle_mm_fault+0xa46/0xef0
  ? do_syscall_64+0x71/0x900
  ksys_read+0x73/0xf0
  do_syscall_64+0x71/0x900
  ? count_memcg_events+0xc2/0x190
  ? handle_mm_fault+0x1d7/0x2d0
  ? do_user_addr_fault+0x21a/0x690
  ? exc_page_fault+0x7e/0x1a0
  entry_SYSCALL_64_after_hwframe+0x6c/0x74
 RIP: 0033:0x7f44d4031687
 Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00>
 RSP: 002b:00007ffdb4b5f0b0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
 RAX: ffffffffffffffda RBX: 00007f44d3f9f740 RCX: 00007f44d4031687
 RDX: 0000000000040000 RSI: 00007f44d3f5e000 RDI: 0000000000000003
 RBP: 0000000000040000 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000202 R12: 00007f44d3f5e000
 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000040000
  </TASK>
 Modules linked in: tls tcp_diag inet_diag xt_mark ccm snd_hrtimer snd_seq_dummy snd_seq_midi snd_seq_oss snd_seq_midi_event snd_rawmidi snd_seq snd_seq_device x>
  snd_hda_codec_atihdmi snd_hda_codec_realtek_lib lenovo_wmi_helpers think_lmi snd_hda_codec_generic snd_hda_codec_hdmi snd_soc_core kvm snd_compress uvcvideo sn>
  platform_profile joydev amd_pmc mousedev mac_hid sch_fq_codel uinput i2c_dev parport_pc ppdev lp parport nvme_fabrics loop nfnetlink ip_tables x_tables dm_cryp>
 CR2: 0000000000000000
 ---[ end trace 0000000000000000 ]---
 RIP: 0010:odm_combine_segments_show+0x93/0xf0 [amdgpu]
 Code: 41 83 b8 b0 00 00 00 01 75 6e 48 98 ba a1 ff ff ff 48 c1 e0 0c 48 8d 8c 07 d8 02 00 00 48 85 c9 74 2d 48 8b bc 07 f0 08 00 00 <48> 8b 07 48 8b 80 08 02 00>
 RSP: 0018:ffffd1bf4b953c58 EFLAGS: 00010286
 RAX: 0000000000005000 RBX: ffff8e35976b02d0 RCX: ffff8e3aeed052d8
 RDX: 00000000ffffffa1 RSI: ffff8e35a3120800 RDI: 0000000000000000
 RBP: 0000000000000000 R08: ffff8e3580eb0000 R09: ffff8e35976b02d0
 R10: ffffd1bf4b953c78 R11: 0000000000000000 R12: ffffd1bf4b953d08
 R13: 0000000000040000 R14: 0000000000000001 R15: 0000000000000001
 FS:  00007f44d3f9f740(0000) GS:ffff8e3caa47f000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000000 CR3: 00000006485c2000 CR4: 0000000000f50ef0
 PKRU: 55555554

Fix this by checking pipe_ctx->stream_res.tg before dereferencing.

Fixes: 07926ba ("drm/amd/display: Add debugfs interface for ODM combine info")
Signed-off-by: Rong Zhang <[email protected]>
Reviewed-by: Mario Limoncello <[email protected]>
Signed-off-by: Mario Limonciello <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
(cherry picked from commit f19bbec)
Cc: [email protected]
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
 into HEAD

KVM/riscv fixes for 6.18, take #2

- Fix check for local interrupts on riscv32
- Read HGEIP CSR on the correct cpu when checking for IMSIC interrupts
- Remove automatic I/O mapping from kvm_arch_prepare_memory_region()
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
Add VMX exit handlers for SEAMCALL and TDCALL to inject a #UD if a non-TD
guest attempts to execute SEAMCALL or TDCALL.  Neither SEAMCALL nor TDCALL
is gated by any software enablement other than VMXON, and so will generate
a VM-Exit instead of e.g. a native #UD when executed from the guest kernel.

Note!  No unprivileged DoS of the L1 kernel is possible as TDCALL and
SEAMCALL #GP at CPL > 0, and the CPL check is performed prior to the VMX
non-root (VM-Exit) check, i.e. userspace can't crash the VM. And for a
nested guest, KVM forwards unknown exits to L1, i.e. an L2 kernel can
crash itself, but not L1.

Note #2!  The Intel® Trust Domain CPU Architectural Extensions spec's
pseudocode shows the CPL > 0 check for SEAMCALL coming _after_ the VM-Exit,
but that appears to be a documentation bug (likely because the CPL > 0
check was incorrectly bundled with other lower-priority #GP checks).
Testing on SPR and EMR shows that the CPL > 0 check is performed before
the VMX non-root check, i.e. SEAMCALL #GPs when executed in usermode.

Note #3!  The aforementioned Trust Domain spec uses confusing pseudocode
that says that SEAMCALL will #UD if executed "inSEAM", but "inSEAM"
specifically means in SEAM Root Mode, i.e. in the TDX-Module.  The long-
form description explicitly states that SEAMCALL generates an exit when
executed in "SEAM VMX non-root operation".  But that's a moot point as the
TDX-Module injects #UD if the guest attempts to execute SEAMCALL, as
documented in the "Unconditionally Blocked Instructions" section of the
TDX-Module base specification.

Cc: [email protected]
Cc: Kai Huang <[email protected]>
Cc: Xiaoyao Li <[email protected]>
Cc: Rick Edgecombe <[email protected]>
Cc: Dan Williams <[email protected]>
Cc: Binbin Wu <[email protected]>
Reviewed-by: Kai Huang <[email protected]>
Reviewed-by: Binbin Wu <[email protected]>
Reviewed-by: Xiaoyao Li <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Sean Christopherson <[email protected]>
jwrdegoede pushed a commit that referenced this pull request Nov 10, 2025
…/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm654 fixes for 6.18, take #2

* Core fixes

  - Fix trapping regression when no in-kernel irqchip is present
    ([email protected])

  - Check host-provided, untrusted ranges and offsets in pKVM
    ([email protected])
    ([email protected])

  - Fix regression restoring the ID_PFR1_EL1 register
    ([email protected]

  - Fix vgic ITS locking issues when LPIs are not directly injected
    ([email protected])

* Test fixes

  - Correct target CPU programming in vgic_lpi_stress selftest
    ([email protected])

  - Fix exposure of SCTLR2_EL2 and ZCR_EL2 in get-reg-list selftest
    (20251023-b4-kvm-arm64-get-reg-list-sctlr-el2-v1-1-088f88ff992a@kernel.org)
    (20251024-kvm-arm64-get-reg-list-zcr-el2-v1-1-0cd0ff75e22f@kernel.org)

* Misc

  - Update Oliver's email address
    ([email protected])
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