Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752479Ab1BAINY (ORCPT ); Tue, 1 Feb 2011 03:13:24 -0500 Received: from mail-vw0-f46.google.com ([209.85.212.46]:36867 "EHLO mail-vw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751553Ab1BAINX (ORCPT ); Tue, 1 Feb 2011 03:13:23 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:content-transfer-encoding :in-reply-to:user-agent; b=D7bSWIIUUPpk17ImNvhxauNRLxx6dxGTs/LRdr3PYzh7o0bkxZjHonj6YgwcjwxgmN NIBs2zsgE2x8IO4hJRv3yX4Tr5At9O3er4VEptVHa/CT+Wfc9JXKP0d4WgxFyN0LcC34 mnDhS4zPVMezJmaJgHu8+YCubpyVtpp79ZVS0= Date: Tue, 1 Feb 2011 16:13:13 +0800 From: =?utf-8?Q?Am=C3=A9rico?= Wang To: =?utf-8?Q?Am=C3=A9rico?= Wang Cc: "Eric W. Biederman" , Vivek Goyal , kosaki.motohiro@jp.fujitsu.com, linux kernel mailing list , Jarod Wilson , akpm@linux-foundation.org Subject: [Patch] kexec: remove KMSG_DUMP_KEXEC (was Re: Query about kdump_msg hook into crash_kexec()) Message-ID: <20110201081313.GC21239@cr0.nay.redhat.com> References: <20110131225939.GH11974@redhat.com> <20110201071933.GA21239@cr0.nay.redhat.com> <20110201073853.GB21239@cr0.nay.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20110201073853.GB21239@cr0.nay.redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2812 Lines: 92 On Tue, Feb 01, 2011 at 03:38:53PM +0800, Américo Wang wrote: >On Mon, Jan 31, 2011 at 11:33:15PM -0800, Eric W. Biederman wrote: >>The issue is the inane call inside crash_kexec. >> >>It requires both a kexec kernel to be loaded and it requires you to be >>crashing. Given that when I audited the kmsg_dump handlers they really >>weren't safe in a crash dump scenario we should just remove it. >> > >Probably, I think we need to get rid of KMSG_DUMP_KEXEC. > Here we go. ---------> KMSG_DUMP_KEXEC is useless because we already save kernel messages inside /proc/vmcore, and it is unsafe to allow modules to do other stuffs in a crash dump scenario. Reported-by: Vivek Goyal Cc: "Eric W. Biederman" Signed-off-by: WANG Cong --- diff --git a/drivers/char/ramoops.c b/drivers/char/ramoops.c index 1a9f5f6..8653ba4 100644 --- a/drivers/char/ramoops.c +++ b/drivers/char/ramoops.c @@ -69,8 +69,7 @@ static void ramoops_do_dump(struct kmsg_dumper *dumper, struct timeval timestamp; if (reason != KMSG_DUMP_OOPS && - reason != KMSG_DUMP_PANIC && - reason != KMSG_DUMP_KEXEC) + reason != KMSG_DUMP_PANIC) return; /* Only dump oopses if dump_oops is set */ diff --git a/drivers/mtd/mtdoops.c b/drivers/mtd/mtdoops.c index e3e40f4..56eac4e 100644 --- a/drivers/mtd/mtdoops.c +++ b/drivers/mtd/mtdoops.c @@ -308,8 +308,7 @@ static void mtdoops_do_dump(struct kmsg_dumper *dumper, char *dst; if (reason != KMSG_DUMP_OOPS && - reason != KMSG_DUMP_PANIC && - reason != KMSG_DUMP_KEXEC) + reason != KMSG_DUMP_PANIC) return; /* Only dump oopses if dump_oops is set */ diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h index 2a0d7d6..05fa2a9 100644 --- a/include/linux/kmsg_dump.h +++ b/include/linux/kmsg_dump.h @@ -17,7 +17,6 @@ enum kmsg_dump_reason { KMSG_DUMP_OOPS, KMSG_DUMP_PANIC, - KMSG_DUMP_KEXEC, KMSG_DUMP_RESTART, KMSG_DUMP_HALT, KMSG_DUMP_POWEROFF, diff --git a/kernel/kexec.c b/kernel/kexec.c index ec19b92..3ac0218 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -32,7 +32,6 @@ #include #include #include -#include #include #include @@ -1078,8 +1077,6 @@ void crash_kexec(struct pt_regs *regs) if (kexec_crash_image) { struct pt_regs fixed_regs; - kmsg_dump(KMSG_DUMP_KEXEC); - crash_setup_regs(&fixed_regs, regs); crash_save_vmcoreinfo(); machine_crash_shutdown(&fixed_regs); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/