x86: pull bp calculation earlier into the backtrace path

[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / traps_32.c

diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index 959d40edecd51a021f0d3f548fd88cc18a6f0104..6f3bb287c7026064246617df58baed21a340fe86 100644 (file)
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -120,15 +120,6 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
 {
        struct stack_frame *frame = (struct stack_frame *)bp;
 
-       /*
-        * if EBP is "deeper" into the stack than the actual stack pointer,
-        * we need to rewind the stack pointer a little to start at the
-        * first stack frame, but only if EBP is in this stack frame.
-        */
-       if (stack > (unsigned long *) bp
-                       && valid_stack_ptr(tinfo, frame, sizeof(*frame)))
-               stack = (unsigned long *) bp;
-
        while (valid_stack_ptr(tinfo, stack, sizeof(*stack))) {
                unsigned long addr;
 
@@ -139,7 +130,7 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
                                frame = frame->next_frame;
                                bp = (unsigned long) frame;
                        } else {
-                               ops->address(data, addr, 0);
+                               ops->address(data, addr, bp == 0);
                        }
                }
                stack++;
@@ -150,11 +141,9 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
 #define MSG(msg) ops->warning(data, msg)
 
 void dump_trace(struct task_struct *task, struct pt_regs *regs,
-               unsigned long *stack,
+               unsigned long *stack, unsigned long bp,
                const struct stacktrace_ops *ops, void *data)
 {
-       unsigned long bp = 0;
-
        if (!task)
                task = current;
 
@@ -234,20 +223,20 @@ static const struct stacktrace_ops print_trace_ops = {
 
 static void
 show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
-                  unsigned long * stack, char *log_lvl)
+               unsigned long *stack, unsigned long bp, char *log_lvl)
 {
-       dump_trace(task, regs, stack, &print_trace_ops, log_lvl);
+       dump_trace(task, regs, stack, bp, &print_trace_ops, log_lvl);
        printk("%s =======================\n", log_lvl);
 }
 
 void show_trace(struct task_struct *task, struct pt_regs *regs,
-               unsigned long * stack)
+               unsigned long *stack, unsigned long bp)
 {
-       show_trace_log_lvl(task, regs, stack, "");
+       show_trace_log_lvl(task, regs, stack, bp, "");
 }
 
 static void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
-                              unsigned long *sp, char *log_lvl)
+                      unsigned long *sp, unsigned long bp, char *log_lvl)
 {
        unsigned long *stack;
        int i;
@@ -268,13 +257,13 @@ static void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
                printk("%08lx ", *stack++);
        }
        printk("\n%sCall Trace:\n", log_lvl);
-       show_trace_log_lvl(task, regs, sp, log_lvl);
+       show_trace_log_lvl(task, regs, sp, bp, log_lvl);
 }
 
 void show_stack(struct task_struct *task, unsigned long *sp)
 {
        printk("       ");
-       show_stack_log_lvl(task, NULL, sp, "");
+       show_stack_log_lvl(task, NULL, sp, 0, "");
 }
 
 /*
@@ -283,13 +272,19 @@ void show_stack(struct task_struct *task, unsigned long *sp)
 void dump_stack(void)
 {
        unsigned long stack;
+       unsigned long bp = 0;
+
+#ifdef CONFIG_FRAME_POINTER
+       if (!bp)
+               asm("movl %%ebp, %0" : "=r" (bp):);
+#endif
 
        printk("Pid: %d, comm: %.20s %s %s %.*s\n",
                current->pid, current->comm, print_tainted(),
                init_utsname()->release,
                (int)strcspn(init_utsname()->version, " "),
                init_utsname()->version);
-       show_trace(current, NULL, &stack);
+       show_trace(current, NULL, &stack, bp);
 }
 
 EXPORT_SYMBOL(dump_stack);
@@ -314,7 +309,7 @@ void show_registers(struct pt_regs *regs)
                unsigned char c;
 
                printk("\n" KERN_EMERG "Stack: ");
-               show_stack_log_lvl(NULL, regs, &regs->sp, KERN_EMERG);
+               show_stack_log_lvl(NULL, regs, &regs->sp, 0, KERN_EMERG);
 
                printk(KERN_EMERG "Code: ");