x86: use the stack frames to get exact stack-traces for CONFIG_FRAMEPOINTER on x86-64

[linux-2.6-omap-h63xx.git] / arch / x86 / kernel / traps_64.c

diff --git a/arch/x86/kernel/traps_64.c b/arch/x86/kernel/traps_64.c
index b8303ed950571c758784bf27cdd2007f84b66021..304ca6b4a1caeceae1b42100b1675867983f11a3 100644 (file)
--- a/arch/x86/kernel/traps_64.c
+++ b/arch/x86/kernel/traps_64.c
@@ -225,31 +225,34 @@ static inline int valid_stack_ptr(struct thread_info *tinfo,
        return p > t && p < t + THREAD_SIZE - size;
 }
 
+/* The form of the top of the frame on the stack */
+struct stack_frame {
+       struct stack_frame *next_frame;
+       unsigned long return_address;
+};
+
+
 static inline unsigned long print_context_stack(struct thread_info *tinfo,
                                unsigned long *stack, unsigned long bp,
                                const struct stacktrace_ops *ops, void *data,
                                unsigned long *end)
 {
-       /*
-        * Print function call entries within a stack. 'cond' is the
-        * "end of stackframe" condition, that the 'stack++'
-        * iteration will eventually trigger.
-        */
-       while (valid_stack_ptr(tinfo, stack, 3, end)) {
-               unsigned long addr = *stack++;
-               /* Use unlocked access here because except for NMIs
-                  we should be already protected against module unloads */
+       struct stack_frame *frame = (struct stack_frame *)bp;
+
+       while (valid_stack_ptr(tinfo, stack, sizeof(*stack), end)) {
+               unsigned long addr;
+
+               addr = *stack;
                if (__kernel_text_address(addr)) {
-                       /*
-                        * If the address is either in the text segment of the
-                        * kernel, or in the region which contains vmalloc'ed
-                        * memory, it *may* be the address of a calling
-                        * routine; if so, print it so that someone tracing
-                        * down the cause of the crash will be able to figure
-                        * out the call path that was taken.
-                        */
-                       ops->address(data, addr, 1);
+                       if ((unsigned long) stack == bp + 8) {
+                               ops->address(data, addr, 1);
+                               frame = frame->next_frame;
+                               bp = (unsigned long) frame;
+                       } else {
+                               ops->address(data, addr, bp == 0);
+                       }
                }
+               stack++;
        }
        return bp;
 }
@@ -274,6 +277,19 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
                        stack = (unsigned long *)tsk->thread.sp;
        }
 
+#ifdef CONFIG_FRAME_POINTER
+       if (!bp) {
+               if (tsk == current) {
+                       /* Grab bp right from our regs */
+                       asm("movq %%rbp, %0" : "=r" (bp):);
+               } else {
+                       /* bp is the last reg pushed by switch_to */
+                       bp = *(unsigned long *) tsk->thread.sp;
+               }
+       }
+#endif
+
+
 
        /*
         * Print function call entries in all stacks, starting at the
@@ -290,8 +306,8 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
                        if (ops->stack(data, id) < 0)
                                break;
 
-                       print_context_stack(tinfo, stack, 0, ops,
-                                               data, estack_end);
+                       bp = print_context_stack(tinfo, stack, bp, ops,
+                                                       data, estack_end);
                        ops->stack(data, "<EOE>");
                        /*
                         * We link to the next stack via the
@@ -309,8 +325,8 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
                        if (stack >= irqstack && stack < irqstack_end) {
                                if (ops->stack(data, "IRQ") < 0)
                                        break;
-                               print_context_stack(tinfo, stack, 0, ops,
-                                                        data, irqstack_end);
+                               bp = print_context_stack(tinfo, stack, bp,
+                                               ops, data, irqstack_end);
                                /*
                                 * We link to the next stack (which would be
                                 * the process stack normally) the last
@@ -328,7 +344,7 @@ void dump_trace(struct task_struct *tsk, struct pt_regs *regs,
        /*
         * This handles the process stack:
         */
-       print_context_stack(tinfo, stack, 0, ops, data, NULL);
+       bp = print_context_stack(tinfo, stack, bp, ops, data, NULL);
        put_cpu();
 }
 EXPORT_SYMBOL(dump_trace);
@@ -425,6 +441,11 @@ void dump_stack(void)
        unsigned long dummy;
        unsigned long bp = 0;
 
+#ifdef CONFIG_FRAME_POINTER
+       if (!bp)
+               asm("movq %%rbp, %0" : "=r" (bp):);
+#endif
+
        printk("Pid: %d, comm: %.20s %s %s %.*s\n",
                current->pid, current->comm, print_tainted(),
                init_utsname()->release,