x86: add the capability to print fuzzy backtraces
For enhancing the 32 bit EBP based backtracer, I need the capability
for the backtracer to tell it's customer that an entry is either
reliable or unreliable, and the backtrace printing code then needs to
print the unreliable ones slightly different.
This patch adds the basic capability, the next patch will add a user
of this capability.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/traps_32.c b/arch/x86/kernel/traps_32.c
index acc9af2..8ef8a9d 100644
--- a/arch/x86/kernel/traps_32.c
+++ b/arch/x86/kernel/traps_32.c
@@ -126,7 +126,7 @@
addr = frame->return_address;
if (__kernel_text_address(addr))
- ops->address(data, addr);
+ ops->address(data, addr, 1);
/*
* break out of recursive entries (such as
* end_of_stack_stop_unwind_function). Also,
@@ -145,7 +145,7 @@
addr = *stack++;
if (__kernel_text_address(addr))
- ops->address(data, addr);
+ ops->address(data, addr, 1);
}
#endif
return bp;
@@ -220,9 +220,11 @@
/*
* Print one address/symbol entries per line.
*/
-static void print_trace_address(void *data, unsigned long addr)
+static void print_trace_address(void *data, unsigned long addr, int reliable)
{
printk("%s [<%08lx>] ", (char *)data, addr);
+ if (!reliable)
+ printk("? ");
print_symbol("%s\n", addr);
touch_nmi_watchdog();
}