[PATCH] Fix kernel panic on i386 machine when booting with profile=2

From: Shi, Alex
Date: Wed Sep 30 2009 - 23:24:48 EST



Latest kernel has a kernel panic in booting on i386 machine when profile=2
setting in cmdline. Find it is due to 'sp' incorrect in profile_pc function.

BUG: unable to handle kernel NULL pointer dereference at 00000246
IP: [<c01288b6>] profile_pc+0x2a/0x48
*pde = 00000000
Oops: 0000 [#1] SMP

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxx>
---
arch/x86/kernel/time.c | 5 +++++
1 files changed, 5 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index dcb00d2..c4fedca 100644
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -38,7 +38,12 @@ unsigned long profile_pc(struct pt_regs *regs)
#ifdef CONFIG_FRAME_POINTER
return *(unsigned long *)(regs->bp + sizeof(long));
#else
+#ifdef CONFIG_X86_32
+ unsigned long *sp = (unsigned long *)&regs->sp;
+#else
unsigned long *sp = (unsigned long *)regs->sp;
+
+#endif
/*
* Return address is either directly at stack pointer
* or above a saved flags. Eflags has bits 22-31 zero,
--
1.5.6.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/