patch-2_6_7-vs1_9_1_12

[linux-2.6.git] / arch / i386 / kernel / traps.c

diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index c770d87..f031de0 100644 (file)
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -94,27 +94,70 @@ asmlinkage void machine_check(void);
 
 static int kstack_depth_to_print = 24;
 
-void show_trace(struct task_struct *task, unsigned long * stack)
+static int valid_stack_ptr(struct task_struct *task, void *p)
+{
+       if (p <= (void *)task->thread_info)
+               return 0;
+       if (kstack_end(p))
+               return 0;
+       return 1;
+}
+
+#ifdef CONFIG_FRAME_POINTER
+void print_context_stack(struct task_struct *task, unsigned long *stack,
+                        unsigned long ebp)
 {
        unsigned long addr;
 
-       if (!stack)
-               stack = (unsigned long*)&stack;
+       while (valid_stack_ptr(task, (void *)ebp)) {
+               addr = *(unsigned long *)(ebp + 4);
+               printk(" [<%08lx>] ", addr);
+               print_symbol("%s", addr);
+               printk("\n");
+               ebp = *(unsigned long *)ebp;
+       }
+}
+#else
+void print_context_stack(struct task_struct *task, unsigned long *stack,
+                        unsigned long ebp)
+{
+       unsigned long addr;
 
-       printk("Call Trace:");
-#ifdef CONFIG_KALLSYMS
-       printk("\n");
+       while (!kstack_end(stack)) {
+               addr = *stack++;
+               if (kernel_text_address(addr)) {
+                       printk(" [<%08lx>] ", addr);
+                       print_symbol("%s\n", addr);
+               }
+       }
+}
 #endif
+
+void show_trace(struct task_struct *task, unsigned long * stack)
+{
+       unsigned long ebp;
+
+       if (!task)
+               task = current;
+
+       if (!valid_stack_ptr(task, stack)) {
+               printk("Stack pointer is garbage, not printing trace\n");
+               return;
+       }
+
+       if (task == current) {
+               /* Grab ebp right from our regs */
+               asm ("movl %%ebp, %0" : "=r" (ebp) : );
+       } else {
+               /* ebp is the last reg pushed by switch_to */
+               ebp = *(unsigned long *) task->thread.esp;
+       }
+
        while (1) {
                struct thread_info *context;
-               context = (struct thread_info*) ((unsigned long)stack & (~(THREAD_SIZE - 1)));
-               while (!kstack_end(stack)) {
-                       addr = *stack++;
-                       if (kernel_text_address(addr)) {
-                               printk(" [<%08lx>] ", addr);
-                               print_symbol("%s\n", addr);
-                       }
-               }
+               context = (struct thread_info *)
+                       ((unsigned long)stack & (~(THREAD_SIZE - 1)));
+               print_context_stack(task, stack, ebp);
                stack = (unsigned long*)context->previous_esp;
                if (!stack)
                        break;
@@ -143,7 +186,7 @@ void show_stack(struct task_struct *task, unsigned long *esp)
                        printk("\n       ");
                printk("%08lx ", *stack++);
        }
-       printk("\n");
+       printk("\nCall Trace:\n");
        show_trace(task, esp);
 }
 
@@ -240,7 +283,7 @@ static void handle_BUG(struct pt_regs *regs)
                file = "<bad filename>";
 
        printk("------------[ cut here ]------------\n");
-       printk("kernel BUG at %s:%d!\n", file, line);
+       printk(KERN_ALERT "kernel BUG at %s:%d!\n", file, line);
 
 no_bug:
        return;
@@ -261,7 +304,7 @@ void die(const char * str, struct pt_regs * regs, long err)
        spin_lock_irq(&die_lock);
        bust_spinlocks(1);
        handle_BUG(regs);
-       printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
+       printk(KERN_ALERT "%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
 #ifdef CONFIG_PREEMPT
        printk("PREEMPT ");
        nl = 1;