lkml.org 
[lkml]   [2009]   [Mar]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[patch 4/7] xtensa: use correct stack pointer for stack traces
Right now, the xtensa stacktrace code reads the _current_ kernel stack
pointer if nothing is supplied. With debugging facilities like sysrq
this means that the backtrace of the sysrq-handler is printed instead
of a trace of the given task's stack.

When no stack pointer is specified in show_trace() and show_stack(),
use the stack pointer that comes with the handed in task descriptor to
make stack traces more useful.

Signed-off-by: Johannes Weiner <jw@emlix.com>
---
arch/xtensa/kernel/traps.c | 14 ++++++--------
1 file changed, 6 insertions(+), 8 deletions(-)

--- a/arch/xtensa/kernel/traps.c
+++ b/arch/xtensa/kernel/traps.c
@@ -372,11 +372,10 @@ void show_trace(struct task_struct *task
unsigned long a0, a1, pc;
unsigned long sp_start, sp_end;

- a1 = (unsigned long)sp;
-
- if (a1 == 0)
- __asm__ __volatile__ ("mov %0, a1\n" : "=a"(a1));
-
+ if (sp)
+ a1 = (unsigned long)sp;
+ else
+ a1 = task->thread.sp;

sp_start = a1 & ~(THREAD_SIZE-1);
sp_end = sp_start + THREAD_SIZE;
@@ -418,9 +417,8 @@ void show_stack(struct task_struct *task
int i = 0;
unsigned long *stack;

- if (sp == 0)
- __asm__ __volatile__ ("mov %0, a1\n" : "=a"(sp));
-
+ if (!sp)
+ sp = (unsigned long *)task->thread.sp;
stack = sp;

printk("\nStack: ");
--



\
 
 \ /
  Last update: 2009-03-02 18:01    [W:0.024 / U:0.672 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site