Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753964AbbBTIbk (ORCPT ); Fri, 20 Feb 2015 03:31:40 -0500 Received: from mgwkm03.jp.fujitsu.com ([202.219.69.170]:47188 "EHLO mgwkm03.jp.fujitsu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753186AbbBTIbj (ORCPT ); Fri, 20 Feb 2015 03:31:39 -0500 X-SecurityPolicyCheck: OK by SHieldMailChecker v2.2.3 X-SHieldMailCheckerPolicyVersion: FJ-ISEC-20140219-2 Message-ID: <54E6F0D9.2000607@jp.fujitsu.com> Date: Fri, 20 Feb 2015 17:31:21 +0900 From: "HATAYAMA, Daisuke" User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: ebiederm@xmission.com, vgoyal@redhat.com CC: masami.hiramatsu.pt@hitachi.com, linux-kernel@vger.kernel.org, kexec@lists.infradead.org Subject: Re: [PATCH] kernel/panic/kexec: fix "crash_kexec_post_notifiers" option issue in oops path References: <20150205.175943.381586636.d.hatayama@jp.fujitsu.com> In-Reply-To: <20150205.175943.381586636.d.hatayama@jp.fujitsu.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2479 Lines: 75 Hello Eric, Vivek, Do you have any comment to this patch? On 2015/02/05 17:59, HATAYAMA Daisuke wrote: > The commit f06e5153f4ae2e2f3b0300f0e260e40cb7fefd45 introduced > "crash_kexec_post_notifiers" kernel boot option, which toggles > wheather panic() calls crash_kexec() before or after panic_notifiers > and dump kmsg. > > The problem is that the commit overlooks panic_on_oops kernel boot > option. If it is enabled, crash_kexec() is called directly without > going through panic() in oops path. > > To fix this issue, this patch adds a check to > "crash_kexec_post_notifiers" in the condition of kexec_should_crash(). > > Signed-off-by: HATAYAMA Daisuke > --- > include/linux/kernel.h | 3 +++ > kernel/kexec.c | 2 ++ > kernel/panic.c | 2 +- > 3 files changed, 6 insertions(+), 1 deletion(-) > > diff --git a/include/linux/kernel.h b/include/linux/kernel.h > index 64ce58b..f47379f 100644 > --- a/include/linux/kernel.h > +++ b/include/linux/kernel.h > @@ -426,6 +426,9 @@ extern int panic_on_unrecovered_nmi; > extern int panic_on_io_nmi; > extern int panic_on_warn; > extern int sysctl_panic_on_stackoverflow; > + > +extern bool crash_kexec_post_notifiers; > + > /* > * Only to be used by arch init code. If the user over-wrote the default > * CONFIG_PANIC_TIMEOUT, honor it. > diff --git a/kernel/kexec.c b/kernel/kexec.c > index 9a8a01a..0ecf252 100644 > --- a/kernel/kexec.c > +++ b/kernel/kexec.c > @@ -84,6 +84,8 @@ struct resource crashk_low_res = { > > int kexec_should_crash(struct task_struct *p) > { > + if (crash_kexec_post_notifiers) > + return 0; > if (in_interrupt() || !p->pid || is_global_init(p) || panic_on_oops) > return 1; > return 0; > diff --git a/kernel/panic.c b/kernel/panic.c > index 4d8d6f9..6582546 100644 > --- a/kernel/panic.c > +++ b/kernel/panic.c > @@ -32,7 +32,7 @@ static unsigned long tainted_mask; > static int pause_on_oops; > static int pause_on_oops_flag; > static DEFINE_SPINLOCK(pause_on_oops_lock); > -static bool crash_kexec_post_notifiers; > +bool crash_kexec_post_notifiers; > int panic_on_warn __read_mostly; > > int panic_timeout = CONFIG_PANIC_TIMEOUT; > -- Thanks. HATAYAMA, Daisuke -- 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/