From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galois.linutronix.de ([2001:470:1f0b:db:abcd:42:0:1]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1ZmGSJ-0004mA-D7 for kexec@lists.infradead.org; Wed, 14 Oct 2015 07:26:36 +0000 Date: Wed, 14 Oct 2015 09:25:18 +0200 (CEST) From: Thomas Gleixner Subject: RE: [V4 PATCH 4/4] x86/apic: Introduce noextnmi boot option In-Reply-To: <04EAB7311EE43145B2D3536183D1A844549BAEA9@GSjpTKYDCembx31.service.hitachi.net> Message-ID: References: <20150925112803.4258.94241.stgit@softrs> <20150925112811.4258.54494.stgit@softrs> <04EAB7311EE43145B2D3536183D1A844549BAEA9@GSjpTKYDCembx31.service.hitachi.net> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="8323329-1300212950-1444807519=:25029" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "kexec" Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: =?ISO-2022-JP?Q?=1B$B2O9g1Q9=28=1B=28J_=2F_KAWAI=1B$B!$=1B=28JHIDEHIRO?= Cc: "x86@kernel.org" , Jonathan Corbet , Peter Zijlstra , "linux-doc@vger.kernel.org" , "kexec@lists.infradead.org" , "linux-kernel@vger.kernel.org" , Michal Hocko , Ingo Molnar , "Eric W. Biederman" , "H. Peter Anvin" , =?ISO-2022-JP?Q?=1B$BJ=3F=3E=3E2mL&=1B=28J_=2F_HIRAMATU=1B$B!$=1B=28JMASAMI?= , Andrew Morton , Ingo Molnar , Vivek Goyal This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --8323329-1300212950-1444807519=:25029 Content-Type: TEXT/PLAIN; charset="utf-8" Content-Transfer-Encoding: 8bit On Wed, 14 Oct 2015, 河合英宏 / KAWAI，HIDEHIRO wrote: > > On Fri, 25 Sep 2015, Hidehiro Kawai wrote: > > > > > This patch introduces new boot option "noextnmi" which disables > > > external NMI. This option is useful for the dump capture kernel > > > so that an HA application or administrator wouldn't mistakenly > > > shoot down the kernel by NMI. > > > > > > Currently, only x86 supports this option. > > > > You might add that is can be used for debugging purposes as > > well. External NMIs can be their own source of trouble. :) > > Thanks for your comments! I'll do that. > > By the way, I have a pending patch which expands this option like > this: > > apic_extnmi={ bsp | all | none } > > If apic_extnmi=all is specified, external NMIs are broadcast to > all CPUs. This raises the successful rate of kernel panic in the case > where an external NMI to CPU 0 is swallowed by other NMI handlers or > blocked due to hang-up in NMI context. The patch works without any > problems, but I'm going to drop the feature if it will cause long > discussion. I'd like to settle this patch set down once. At least, > I'm going to change this option to apic_extnmi={bsp|none} style for > the future expansion. > > How do you think about this? Do it right away with all three variants. They make a lot of sense to me. Thanks, tglx --8323329-1300212950-1444807519=:25029 Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec --8323329-1300212950-1444807519=:25029--