From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Y71xB-00055w-L1 for kexec@lists.infradead.org; Fri, 02 Jan 2015 13:07:46 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t02D7Llx030995 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Fri, 2 Jan 2015 08:07:21 -0500 Message-ID: <54A69808.4010401@redhat.com> Date: Fri, 02 Jan 2015 08:07:20 -0500 From: Prarit Bhargava MIME-Version: 1.0 Subject: Re: [PATCH] kexec, remove panic_on_warn kernel parameter from kdump situations References: <1419951471-19765-1-git-send-email-prarit@redhat.com> <20150102125423.GA18785@redhat.com> In-Reply-To: <20150102125423.GA18785@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Vivek Goyal Cc: Dave Young , kexec@lists.infradead.org, WANG Chao On 01/02/2015 07:54 AM, Vivek Goyal wrote: > On Tue, Dec 30, 2014 at 09:57:51AM -0500, Prarit Bhargava wrote: >> panic_on_warn kernel parameter will cause the kernel to panic when a >> WARN() is hit in the kernel. This is not a good situation for the kdump >> kernel because then it would be possible for the kdump kernel to panic in >> a non-fatal WARN(). >> >> This patch removes panic_on_warn as a kernel parameter for the kdump >> kernel. >> > > I think modifying kexec-tools is not best place for this. It probably is better to take care of this in distribution specific scripts. > > In the past we have learnt that it is best that kexec-tools does least > amount of manipulation with command line. Well .. here's the question to think about: what does adding panic_on_warn to the kdump kernel get you? AFAICT, nothing. If panic_on_warn is specified, the only thing that will happen is that kdump will fail (which is always bad IMO). There is no real difference in the stack trace between the WARN() and panic situations so there is no information loss. So I disagree -- we should never specify panic_on_warn on kdump kernel. P. > > Thanks > Vivek > >> Signed-off-by: Prarit Bhargava >> Cc: Dave Young >> Cc: Vivek Goyal >> Cc: WANG Chao >> --- >> kexec/kexec.c | 4 +++- >> 1 file changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/kexec/kexec.c b/kexec/kexec.c >> index b088916..323cafb 100644 >> --- a/kexec/kexec.c >> +++ b/kexec/kexec.c >> @@ -1048,8 +1048,10 @@ char *get_command_line(void) >> line[strlen(line) - 1] = '\0'; >> >> remove_parameter(line, "BOOT_IMAGE"); >> - if (kexec_flags & KEXEC_ON_CRASH) >> + if (kexec_flags & KEXEC_ON_CRASH) { >> remove_parameter(line, "crashkernel"); >> + remove_parameter(line, "panic_on_warn"); >> + } >> >> return line; >> } >> -- >> 1.7.9.3 _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec