Add warning functionality (warning(), WARN() and WARN_ON())

arch/x86/extables.c

@@ -29,7 +29,7 @@
 void init_extables(void) {
     for (extable_entry_t *cur = __start_extables; cur < __stop_extables; ++cur) {
         if (!cur->fixup && !cur->cb)
-            panic("extable entry #%d for addr 0x%lx lacks fixup and callback!\n",
-                  cur - __start_extables, cur->fault_addr);
+            warning("extable entry #%d for addr 0x%lx lacks fixup and callback!",
+                    cur - __start_extables, cur->fault_addr);
     }
 }

arch/x86/traps.c

@@ -315,7 +315,7 @@ void do_exception(cpu_regs_t *regs) {
         x86_ex_decode_error_code(ec_str, sizeof(ec_str), regs->exc.vector, regs->exc.error_code);
 
     snprintf(panic_str, sizeof(panic_str),
-             "#%s %sat IP: 0x%02x:0x%016lx SP: 0x%02x:0x%016lx\n",
+             "#%s %sat IP: 0x%02x:0x%016lx SP: 0x%02x:0x%016lx",
              exception_names[regs->exc.vector], ec_str, regs->exc.cs, regs->exc._ASM_IP, regs->exc.ss,
              regs->exc._ASM_SP);
 

common/acpi.c

@@ -87,7 +87,8 @@ static inline bool validate_rsdp(rsdp_rev1_t *ptr) {
         size = sizeof(rsdp_rev2_t);
         break;
     default:
-        panic("Unknown ACPI revision: %u\n", ptr->rev);
+        warning("Unknown ACPI revision: %u", ptr->rev);
+        return false;
     }
 
     if (get_checksum(ptr, size) != 0x0)
@@ -141,7 +142,7 @@ static unsigned acpi_table_map_pages(paddr_t pa, size_t len) {
 
     for (unsigned i = 0; i < num_pages; i++, mfn++) {
         if (mfn_invalid(mfn)) {
-            panic("ACPI table at %p of length %lx has invalid MFN: %lx\n", _ptr(pa), len,
+            panic("ACPI table at %p of length %lx has invalid MFN: %lx", _ptr(pa), len,
                   mfn);
         }
 
@@ -366,7 +367,8 @@ static int process_madt_entries(void) {
             break;
         }
         default:
-            panic("Unknown ACPI MADT entry type: %u\n", entry->type);
+            warning("Unknown ACPI MADT entry type: %u", entry->type);
+            break;
         }
     }
 
@@ -681,7 +683,7 @@ static void madt_parser(ACPI_SUBTABLE_HEADER *entry, void *arg) {
         break;
     }
     default:
-        panic("ACPI [MADT]: Unsupported subtable entry type: %x\n", entry->Type);
+        warning("ACPI [MADT]: Unsupported subtable entry type: %x", entry->Type);
         break;
     }
 }

common/cmdline.c

@@ -130,7 +130,7 @@ void __text_init cmdline_parse(const char *cmdline) {
                     !!parse_bool(!strcmp(optval, optkey) ? "1" : optval);
                 break;
             default:
-                panic("Unkown cmdline type detected...");
+                warning("Unkown cmdline type \"%u\" for %s", param->type, param->name);
                 break;
             }
         }

common/console.c

@@ -52,7 +52,7 @@ void vprintk(const char *fmt, va_list args) {
     rc = vsnprintf(buf, sizeof(buf), fmt, args);
 
     if (rc > (int) sizeof(buf))
-        panic("vprintk() buffer overflow\n");
+        panic("vprintk() buffer overflow");
 
     for (i = 0; i < num_console_callbacks; i++) {
         void *arg = console_callbacks[i].arg;
@@ -125,15 +125,28 @@ void register_console_callback(console_callback_t cb, void *arg) {
 void __noreturn panic(const char *fmt, ...) {
     va_list args;
 
-    printk("******************************\n");
-    printk("CPU[%u] PANIC: ", smp_processor_id());
+    printk("************** PANIC **************\n");
+    printk("CPU[%u]: ", smp_processor_id());
 
     va_start(args, fmt);
     vprintk(fmt, args);
     va_end(args);
 
-    printk("******************************\n");
+    printk("\n***********************************\n");
 
     while (1)
         halt();
 }
+
+void warning(const char *fmt, ...) {
+    va_list args;
+
+    printk("************* WARNING *************\n");
+    printk("CPU[%u]: ", smp_processor_id());
+
+    va_start(args, fmt);
+    vprintk(fmt, args);
+    va_end(args);
+
+    printk("\n***********************************\n");
+}

common/sched.c

@@ -112,7 +112,7 @@ static int prepare_task(task_t *task, const char *name, task_func_t func, void *
     if (!task)
         return -EINVAL;
 
-    BUG_ON(get_task_state(task) > TASK_STATE_READY);
+    ASSERT(get_task_state(task) <= TASK_STATE_READY);
 
     task->name = name;
     task->func = func;
@@ -179,7 +179,7 @@ int schedule_task(task_t *task, cpu_t *cpu) {
         return -EEXIST;
     }
 
-    BUG_ON(get_task_state(task) != TASK_STATE_READY);
+    ASSERT(get_task_state(task) == TASK_STATE_READY);
 
     printk("CPU[%u]: Scheduling task %s[%u] (%s)\n", cpu->id, task->name, task->id,
            task_repeat_string(task->repeat));

drivers/acpi/acpica/osl.c

@@ -85,7 +85,8 @@ ACPI_STATUS AcpiOsSignal(UINT32 Function, void *Info) {
         printk("ACPI: Received ACPI_SIGNAL_BREAKPOINT: %s", bp_msg ?: "");
     } break;
     default:
-        BUG();
+        warning("ACPI: Unsupported ACPI signal: %u", Function);
+        break;
     }
 
     return AE_OK;

drivers/fb/fb.c

@@ -93,10 +93,6 @@ void init_framebuffer(const struct multiboot2_tag_framebuffer *fb) {
     banner_size = (size_t) width * (LOGO_HEIGHT + FONT_SIZE);
 
     switch (bpp) {
-    case 0 ... 7:
-        printk("FB: Unsupported framebuffer BPP: %u\n", bpp);
-        has_fb = false;
-        return;
     case 8:
         put_pixel = put_pixel8;
         break;
@@ -117,7 +113,9 @@ void init_framebuffer(const struct multiboot2_tag_framebuffer *fb) {
         banner_size *= 4;
         break;
     default:
-        BUG();
+        warning("FB: Unsupported framebuffer BPP: %u", bpp);
+        has_fb = false;
+        return;
     }
 
     line_width = pitch * FONT_SIZE;

drivers/serial.c

@@ -51,7 +51,8 @@ static inline const char *com_name(com_idx_t com) {
     case COM4:
         return "COM4";
     default:
-        BUG();
+        warning("Invalid COM port %u\n", com);
+        return NULL;
     }
 }
 

include/console.h

@@ -52,5 +52,6 @@ extern void fb_console_write(void *arg, const char *buf, size_t len);
 extern void register_console_callback(console_callback_t func, void *arg);
 
 extern void panic(const char *fmt, ...);
+extern void warning(const char *fmt, ...);
 
 #endif /* KTF_CONSOLE_H */

include/lib.h

@@ -350,18 +350,28 @@ static inline void sysret(void) {
 
 #define BUG()                                                                            \
     do {                                                                                 \
-        panic("BUG in %s() at line %u\n", __func__, __LINE__);                           \
+        panic("BUG in %s() at line %u", __func__, __LINE__);                             \
     } while (true)
 #define BUG_ON(cond)                                                                     \
     do {                                                                                 \
         if ((cond))                                                                      \
             BUG();                                                                       \
     } while (0)
 
+#define WARN(msg)                                                                        \
+    do {                                                                                 \
+        warning("Warning in %s() at line %u: %s", __func__, __LINE__, (msg));            \
+    } while (0)
+#define WARN_ON(cond, msg)                                                               \
+    do {                                                                                 \
+        if ((cond))                                                                      \
+            WARN((msg));                                                                 \
+    } while (0)
+
 #define ASSERT(cond)                                                                     \
     do {                                                                                 \
         if (!(cond))                                                                     \
-            panic("%s: Assert at %d failed: %s\n", __func__, __LINE__, STR((cond)));     \
+            panic("%s: Assert at %d failed: %s", __func__, __LINE__, STR((cond)));       \
     } while (0)
 
 /* I/O Ports handling */

mm/pmm.c

@@ -83,7 +83,7 @@ static frames_array_t *new_frames_array(void) {
         array = get_free_page(GFP_KERNEL);
 
     if (!array)
-        panic("PMM: Unable to allocate new page for frame array\n");
+        panic("PMM: Unable to allocate new page for frame array");
 
     dprintk("%s: allocated new frames array: %p\n", __func__, array);
 
@@ -109,15 +109,11 @@ static bool is_frames_array_free(const frames_array_t *array) {
     if (array->meta.free_count < ARRAY_SIZE(array->frames))
         return false;
     else if (array->meta.free_count > ARRAY_SIZE(array->frames))
-        panic("PMM: incorrect number of free slots: %d in array: %p\n",
+        panic("PMM: incorrect number of free slots: %d in array: %p",
               array->meta.free_count, array);
 
-    for (unsigned i = 0; i < ARRAY_SIZE(array->frames); i++) {
-        const frame_t *frame = &array->frames[i];
-
-        if (!is_frame_free(frame))
-            panic("PMM: found occupied slot in an empty array: %p\n", array);
-    }
+    for (unsigned i = 0; i < ARRAY_SIZE(array->frames); i++)
+        ASSERT(is_frame_free(&array->frames[i]));
 
     return true;
 }
@@ -171,7 +167,7 @@ static inline frame_t *take_frame(frame_t *frame, frames_array_t *array) {
 }
 
 static inline frame_t *put_frames_array_entry(frame_t *frame, frames_array_t *array) {
-    BUG_ON(is_frame_free(frame));
+    ASSERT(!is_frame_free(frame));
 
     if (!array)
         array = find_frames_array(frame);
@@ -190,7 +186,7 @@ static inline frame_t *get_frames_array_entry(void) {
     frames_array_t *array = get_frames_array();
 
     if (!array)
-        panic("PMM: Unable to get a free array of frames' metadata\n");
+        panic("PMM: Unable to get a free array of frames' metadata");
 
     for (unsigned i = 0; i < ARRAY_SIZE(array->frames); i++) {
         frame_t *frame = &array->frames[i];
@@ -203,7 +199,7 @@ static inline frame_t *get_frames_array_entry(void) {
 }
 
 static inline void destroy_frame(frame_t *frame) {
-    BUG_ON(is_frame_used(frame));
+    ASSERT(!is_frame_used(frame));
 
     if (frame) {
         list_unlink(&frame->list);
@@ -260,7 +256,7 @@ static unsigned find_first_avail_region(void) {
         return i;
     }
 
-    panic("PMM: Cannot obtain first available physical memory address range\n");
+    panic("PMM: Cannot obtain first available physical memory address range");
     UNREACHABLE();
 }
 
@@ -313,8 +309,8 @@ static size_t process_memory_range(unsigned index, unsigned first_avail_region)
     }
 
     if (cur != end) {
-        panic(
-            "PMM range processing failed: start=0x%016lx end=0x%016lx current=0x%016lx\n",
+        warning(
+            "PMM range processing failed: start=0x%016lx end=0x%016lx current=0x%016lx",
             start, end, cur);
     }
 
@@ -343,12 +339,12 @@ static inline void check_early_frames(unsigned first_avail_region) {
     addr_range_t range;
 
     if (get_avail_memory_range(first_avail_region, &range) < 0)
-        panic("PMM: Cannot obtain first available physical memory address range\n");
+        panic("PMM: Cannot obtain first available physical memory address range");
 
     early_frames_cnt =
         (MB(EARLY_VIRT_MEM) - get_region_free_start(range.start)) / PAGE_SIZE;
     if (frames_count[PAGE_ORDER_4K] < early_frames_cnt) {
-        panic("Not enough early frames: %u missing\n",
+        panic("Not enough early frames: %u missing",
               early_frames_cnt - frames_count[PAGE_ORDER_4K]);
     }
 }
@@ -395,8 +391,7 @@ static inline frame_t *reserve_frame(frame_t *frame) {
 }
 
 static inline bool return_frame(frame_t *frame) {
-    if (!is_frame_used(frame))
-        panic("PMM: trying to return unused frame: %p\n", frame);
+    ASSERT(is_frame_used(frame));
 
     if (--frame->refcount == 0) {
         list_unlink(&frame->list);
@@ -458,7 +453,7 @@ frame_t *get_free_frames_cond(free_frames_cond_t cb) {
 }
 
 static inline void relink_frame_to_order(frame_t *frame, unsigned int new_order) {
-    BUG_ON(new_order > MAX_PAGE_ORDER);
+    ASSERT(new_order <= MAX_PAGE_ORDER);
 
     list_unlink(&frame->list);
     frames_count[frame->order]--;
@@ -548,13 +543,16 @@ void put_free_frames(mfn_t mfn, unsigned int order) {
 
     spin_lock(&lock);
     frame = find_mfn_frame(busy_frames, mfn, order);
-    if (!frame)
-        panic("PMM: unable to find frame: %lx, order: %u among busy frames\n", mfn,
-              order);
+    if (!frame) {
+        warning("PMM: unable to find frame: %lx, order: %u among busy frames", mfn,
+                order);
+        goto unlock;
+    }
 
     if (return_frame(frame))
         merge_frames(frame);
 
+unlock:
     spin_unlock(&lock);
 }
 

mm/regions.c

@@ -85,7 +85,7 @@ addr_range_t get_memory_range(paddr_t pa) {
     memset(&r, 0, sizeof(r));
     if (mbi_get_memory_range(pa, &r) < 0)
         /* FIXME: e820_lower_memory_bound() */
-        panic("Unable to get memory range for: 0x%016lx\n", pa);
+        panic("Unable to get memory range for: 0x%016lx", pa);
 
     return r;
 }

mm/slab.c

@@ -320,7 +320,7 @@ static void ktf_free(void *ptr) {
         }
     }
 
-    panic("Attempted to free %p and couldn't find it\n", ptr);
+    panic("Attempted to free %p and couldn't find it", ptr);
     /* If we reached here, something terribly went wrong */
     UNREACHABLE();
 }

mm/vmm.c

@@ -36,7 +36,7 @@ void *get_free_pages(unsigned int order, gfp_flags_t flags) {
     mfn_t mfn;
 
     if (!boot_flags.virt)
-        panic("Unable to use %s() before final page tables are set\n", __func__);
+        panic("Unable to use %s() before final page tables are set", __func__);
 
     if (!frame)
         return NULL;

smp/mptables.c

@@ -110,8 +110,10 @@ static mpc_hdr_t *get_mpc_addr(const mpf_t *mpf_ptr) {
     mpc_hdr_t *mpc_ptr;
 
     mpc_ptr = paddr_to_virt_kern(mpf_ptr->mpc_base);
-    if (!validate_mpc(mpc_ptr))
-        panic("Incorrect MP Configuration Table found!\n");
+    if (!validate_mpc(mpc_ptr)) {
+        warning("Incorrect MP Configuration Table found!");
+        return NULL;
+    }
 
     return mpc_ptr;
 }
@@ -284,7 +286,8 @@ static void process_mpc_entries(mpc_hdr_t *mpc_ptr) {
             break;
         }
         default:
-            panic("Unknown MP Configuration Table entry type: %x\n", *entry_ptr);
+            warning("Unknown MP Configuration Table entry type: %x", *entry_ptr);
+            break;
         }
     }
 }
@@ -307,6 +310,9 @@ int init_mptables(void) {
     }
 
     mpc_ptr = get_mpc_addr(mpf_ptr);
+    if (!mpc_ptr)
+        return -EINVAL;
+
     if (opt_debug)
         dump_mpc_hdr(mpc_ptr);
     process_mpc_entries(mpc_ptr);