Merge pull request torvalds#262 from liuyuan10/tls

lkl: Fix lkl_sys_halt and memory leak of TIF_HOST_THREAD

Author: tavip

arch/lkl/include/asm/thread_info.h

@@ -49,6 +49,7 @@ void free_thread_stack(unsigned long *);
 
 void threads_init(void);
 void threads_cleanup(void);
+void threads_cnt_dec(void);
 
 #define TIF_SYSCALL_TRACE		0
 #define TIF_NOTIFY_RESUME		1

arch/lkl/kernel/setup.c

@@ -75,6 +75,7 @@ int __init lkl_start_kernel(struct lkl_host_operations *ops,
 	}
 
 	lkl_ops->sem_down(init_sem);
+	lkl_ops->sem_free(init_sem);
 	current_thread_info()->tid = lkl_ops->thread_self();
 	lkl_cpu_change_owner(current_thread_info()->tid);
 
@@ -112,7 +113,8 @@ void machine_restart(char *unused)
 long lkl_sys_halt(void)
 {
 	long err;
-	long params[6] = { 0, };
+	long params[6] = {LINUX_REBOOT_MAGIC1,
+		LINUX_REBOOT_MAGIC2, LINUX_REBOOT_CMD_RESTART, };
 
 	err = lkl_syscall(__NR_reboot, params);
 	if (err < 0)
@@ -158,6 +160,7 @@ static int lkl_run_init(struct linux_binprm *bprm)
 	init_pid_ns.child_reaper = 0;
 
 	syscalls_init();
+	threads_cnt_dec();
 
 	lkl_ops->sem_up(init_sem);
 	lkl_ops->thread_exit();

arch/lkl/kernel/syscalls.c

@@ -113,6 +113,13 @@ long lkl_syscall(long no, long *params)
 
 	ret = run_syscall(no, params);
 
+	if (no == __NR_reboot) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		if (!thread_set_sched_jmp())
+			schedule();
+		return ret;
+	}
+
 out:
 	lkl_cpu_put();
 

arch/lkl/kernel/threads.c

@@ -225,18 +225,23 @@ void threads_init(void)
 	ti->tid = lkl_ops->thread_self();
 }
 
+void threads_cnt_dec(void)
+{
+	__sync_fetch_and_sub(&threads_counter, 1);
+}
+
 void threads_cleanup(void)
 {
-	struct task_struct *p;
+	struct task_struct *p, *t;
 
-	for_each_process(p) {
-		struct thread_info *ti = task_thread_info(p);
+	for_each_process_thread(p, t) {
+		struct thread_info *ti = task_thread_info(t);
 
-		if (p->pid != 1)
-			WARN(!(p->flags & PF_KTHREAD),
-			     "non kernel thread task %p\n", p->comm);
-		WARN(p->state == TASK_RUNNING,
-		     "thread %s still running while halting\n", p->comm);
+		if (t->pid != 1 && !test_ti_thread_flag(ti, TIF_HOST_THREAD))
+			WARN(!(t->flags & PF_KTHREAD),
+			     "non kernel thread task %s\n", t->comm);
+		WARN(t->state == TASK_RUNNING,
+		     "thread %s still running while halting\n", t->comm);
 
 		kill_thread(ti);
 	}

tools/lkl/lib/hijack/init.c

@@ -433,6 +433,7 @@ hijack_fini(void)
 {
 	int i;
 	char *dump = getenv("LKL_HIJACK_DUMP");
+	int err;
 
 	/* The following pauses the kernel before exiting allowing one
 	 * to debug or collect stattistics/diagnosis info from it.
@@ -453,5 +454,7 @@ hijack_fini(void)
 	if (nd)
 		lkl_netdev_free(nd);
 
-	lkl_sys_halt();
+	err = lkl_sys_halt();
+	if (err)
+		fprintf(stderr, "lkl_sys_halt: %s\n", lkl_strerror(err));
 }