1 files changed, 60 insertions, 10 deletions

diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index dcc14477af1f..78464097470a 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -28,6 +28,7 @@
 #include <linux/utsname.h>
 #include <linux/kprobes.h>
 #include <linux/kexec.h>
+#include <linux/unwind.h>
 
 #ifdef CONFIG_EISA
 #include <linux/ioport.h>
@@ -47,7 +48,7 @@
 #include <asm/desc.h>
 #include <asm/i387.h>
 #include <asm/nmi.h>
-
+#include <asm/unwind.h>
 #include <asm/smp.h>
 #include <asm/arch_hooks.h>
 #include <asm/kdebug.h>
@@ -92,6 +93,7 @@ asmlinkage void spurious_interrupt_bug(void);
 asmlinkage void machine_check(void);
 
 static int kstack_depth_to_print = 24;
+static int call_trace = 1;
 ATOMIC_NOTIFIER_HEAD(i386die_chain);
 
 int register_die_notifier(struct notifier_block *nb)
@@ -170,7 +172,23 @@ static inline unsigned long print_context_stack(struct thread_info *tinfo,
         return ebp;
 }
 
-static void show_trace_log_lvl(struct task_struct *task,
+static asmlinkage int show_trace_unwind(struct unwind_frame_info *info, void *log_lvl)
+{
+        int n = 0;
+        int printed = 0; /* nr of entries already printed on current line */
+
+        while (unwind(info) == 0 && UNW_PC(info)) {
+                ++n;
+                printed = print_addr_and_symbol(UNW_PC(info), log_lvl, printed);
+                if (arch_unw_user_mode(info))
+                        break;
+        }
+        if (printed)
+                printk("\n");
+        return n;
+}
+
+static void show_trace_log_lvl(struct task_struct *task, struct pt_regs *regs,
                                unsigned long *stack, char *log_lvl)
 {
         unsigned long ebp;
@@ -178,6 +196,26 @@ static void show_trace_log_lvl(struct task_struct *task,
         if (!task)
                 task = current;
 
+        if (call_trace >= 0) {
+                int unw_ret = 0;
+                struct unwind_frame_info info;
+
+                if (regs) {
+                        if (unwind_init_frame_info(&info, task, regs) == 0)
+                                unw_ret = show_trace_unwind(&info, log_lvl);
+                } else if (task == current)
+                        unw_ret = unwind_init_running(&info, show_trace_unwind, log_lvl);
+                else {
+                        if (unwind_init_blocked(&info, task) == 0)
+                                unw_ret = show_trace_unwind(&info, log_lvl);
+                }
+                if (unw_ret > 0) {
+                        if (call_trace > 0)
+                                return;
+                        printk("%sLegacy call trace:\n", log_lvl);
+                }
+        }
+
         if (task == current) {
                 /* Grab ebp right from our regs */
                 asm ("movl %%ebp, %0" : "=r" (ebp) : );
@@ -198,13 +236,13 @@ static void show_trace_log_lvl(struct task_struct *task,
         }
 }
 
-void show_trace(struct task_struct *task, unsigned long * stack)
+void show_trace(struct task_struct *task, struct pt_regs *regs, unsigned long * stack)
 {
-        show_trace_log_lvl(task, stack, "");
+        show_trace_log_lvl(task, regs, stack, "");
 }
 
-static void show_stack_log_lvl(struct task_struct *task, unsigned long *esp,
-                               char *log_lvl)
+static void show_stack_log_lvl(struct task_struct *task, struct pt_regs *regs,
+                               unsigned long *esp, char *log_lvl)
 {
         unsigned long *stack;
         int i;
@@ -225,13 +263,13 @@ static void show_stack_log_lvl(struct task_struct *task, unsigned long *esp,
                 printk("%08lx ", *stack++);
         }
         printk("\n%sCall Trace:\n", log_lvl);
-        show_trace_log_lvl(task, esp, log_lvl);
+        show_trace_log_lvl(task, regs, esp, log_lvl);
 }
 
 void show_stack(struct task_struct *task, unsigned long *esp)
 {
         printk("       ");
-        show_stack_log_lvl(task, esp, "");
+        show_stack_log_lvl(task, NULL, esp, "");
 }
 
 /*
@@ -241,7 +279,7 @@ void dump_stack(void)
 {
         unsigned long stack;
 
-        show_trace(current, &stack);
+        show_trace(current, NULL, &stack);
 }
 
 EXPORT_SYMBOL(dump_stack);
@@ -285,7 +323,7 @@ void show_registers(struct pt_regs *regs)
                 u8 __user *eip;
 
                 printk("\n" KERN_EMERG "Stack: ");
-                show_stack_log_lvl(NULL, (unsigned long *)esp, KERN_EMERG);
+                show_stack_log_lvl(NULL, regs, (unsigned long *)esp, KERN_EMERG);
 
                 printk(KERN_EMERG "Code: ");
 
@@ -1215,3 +1253,15 @@ static int __init kstack_setup(char *s)
         return 1;
 }
 __setup("kstack=", kstack_setup);
+
+static int __init call_trace_setup(char *s)
+{
+        if (strcmp(s, "old") == 0)
+                call_trace = -1;
+        else if (strcmp(s, "both") == 0)
+                call_trace = 0;
+        else if (strcmp(s, "new") == 0)
+                call_trace = 1;
+        return 1;
+}
+__setup("call_trace=", call_trace_setup);