lkml.org 
[lkml]   [2009]   [Oct]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
SubjectRE: [tip:x86/urgent] x86: fix kernel panic on 32 bits when profiling
Yes, it seems better than mine. 

BRG
Alex

-----Original Message-----
From: tip tree robot [mailto:bounces.tip@hpa.at.zytor.com] On Behalf Of tip-bot for H. Peter Anvin
Sent: 2009年10月13日 2:58
To: linux-tip-commits@vger.kernel.org
Cc: Chen, Tim C; hpa@zytor.com; mingo@redhat.com; akpm@linux-foundation.org; Shi, Alex; tglx@linutronix.de; rjw@sisk.pl
Subject: [tip:x86/urgent] x86: fix kernel panic on 32 bits when profiling

Commit-ID: d1705c558c95418378b11a0be963fe1b3e2fa381
Gitweb: http://git.kernel.org/tip/d1705c558c95418378b11a0be963fe1b3e2fa381
Author: H. Peter Anvin <hpa@zytor.com>
AuthorDate: Mon, 12 Oct 2009 11:32:31 -0700
Committer: H. Peter Anvin <hpa@zytor.com>
CommitDate: Mon, 12 Oct 2009 11:53:51 -0700

x86: fix kernel panic on 32 bits when profiling

Latest kernel has a kernel panic in booting on i386 machine when
profile=2 setting in cmdline. It is due to 'sp' being incorrect in
profile_pc().

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

This differs from the original version by Alex Shi in that we use the
kernel_stack_pointer() inline already defined in <asm/ptrace.h> for
this purpose, instead of #ifdef.

Originally-by: Alex Shi <alex.shi@intel.com>
Cc: "Chen, Tim C" <tim.c.chen@intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
---
arch/x86/kernel/time.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/arch/x86/kernel/time.c b/arch/x86/kernel/time.c
index dcb00d2..be25734 100644
--- a/arch/x86/kernel/time.c
+++ b/arch/x86/kernel/time.c
@@ -38,7 +38,8 @@ unsigned long profile_pc(struct pt_regs *regs)
#ifdef CONFIG_FRAME_POINTER
return *(unsigned long *)(regs->bp + sizeof(long));
#else
- unsigned long *sp = (unsigned long *)regs->sp;
+ unsigned long *sp =
+ (unsigned long *)kernel_stack_pointer(regs);
/*
* Return address is either directly at stack pointer
* or above a saved flags. Eflags has bits 22-31 zero,
\
 
 \ /
  Last update: 2009-10-13 07:41    [W:3.561 / U:0.544 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site