linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Don Zickus <dzickus@redhat.com>
To: Yinghai Lu <yinghai@kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
	linux-kernel@vger.kernel.org, mingo@redhat.com, hpa@zytor.com,
	torvalds@linux-foundation.org, kexec@lists.infradead.org,
	vgoyal@redhat.com, akpm@linux-foundation.org, tglx@linutronix.de,
	mingo@elte.hu, linux-tip-commits@vger.kernel.org
Subject: Re: [tip:x86/debug] x86/kdump: No need to disable ioapic/ lapic in crash path
Date: Thu, 16 Feb 2012 16:56:03 -0500	[thread overview]
Message-ID: <20120216215603.GH9751@redhat.com> (raw)
In-Reply-To: <CAE9FiQVhbAM9vjx-uFcuc0ndsUp0aez9_TsQHStje5G5iwYbag@mail.gmail.com>

On Thu, Feb 16, 2012 at 01:53:29PM -0800, Yinghai Lu wrote:
> On Thu, Feb 16, 2012 at 9:27 AM, Don Zickus <dzickus@redhat.com> wrote:
> 
> > So I think I figured it out.  I went through and commented out code in
> > disable_local_APIC until I narrowed it down to the piece of code that
> > needs to be disabled for it to work.
> >
> > Surprise, surprise... its LVTPC or perf! :-)  Actually it is the
> > nmi_watchdog which uses perf.  My theory is NMIs are not disabled and one
> > is generated by the local apic during decompression (just bad timing) and
> > *splat*.
> >
> > Yinghai, you can probably prove this by
> >
> > echo 0 > /proc/sys/kernel/nmi_watchdog
> >
> > then do your kdump crash test.
> 
> yes.  that will make kdump crash working.

Cool.  Thanks.

Eric,

Just let me know how you want to handle disabling NMIs in the kexec in
panic shutdown case.

Cheers,
Don

  reply	other threads:[~2012-02-16 22:10 UTC|newest]

Thread overview: 63+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <tip-d9bc9be89629445758670220787683e37c93f6c1@git.kernel.org>
2012-02-12  1:04 ` [tip:x86/debug] x86/kdump: No need to disable ioapic/ lapic in crash path Yinghai Lu
2012-02-12  3:13   ` Eric W. Biederman
2012-02-12  4:17     ` Yinghai Lu
2012-02-13 12:52       ` Eric W. Biederman
2012-02-13 16:51         ` Yinghai Lu
2012-02-13 18:16           ` Yinghai Lu
2012-02-16 17:27             ` Don Zickus
2012-02-16 21:53               ` Yinghai Lu
2012-02-16 21:56                 ` Don Zickus [this message]
2012-02-17  3:38                   ` Eric W. Biederman
2012-02-17 12:41                     ` Eric W. Biederman
2012-02-17 15:49                       ` HATAYAMA Daisuke
2012-02-17 20:18                         ` Don Zickus
2012-02-20  5:17                           ` HATAYAMA Daisuke
2012-02-20 15:24                             ` Don Zickus
2012-02-17 19:54                       ` Don Zickus
2012-02-18  3:21                         ` Eric W. Biederman
2012-02-20 15:14                           ` Don Zickus
2012-02-21  8:01                             ` Eric W. Biederman
2012-02-21 13:59                               ` Don Zickus
2012-02-29 23:19                                 ` Eric W. Biederman
2012-03-07 10:53                                   ` Fernando Luis Vázquez Cao
2012-03-07 10:54                                     ` [PATCH 1/2] boot: ignore early NMIs Fernando Luis Vázquez Cao
2012-03-07 10:56                                       ` [PATCH 2/2] boot: add early NMI counter Fernando Luis Vázquez Cao
2012-03-08  4:50                                         ` Eric W. Biederman
2012-03-08  6:00                                           ` Fernando Luis Vázquez Cao
2012-03-08  4:41                                       ` [PATCH 1/2] boot: ignore early NMIs Eric W. Biederman
2012-03-08  5:53                                         ` Fernando Luis Vázquez Cao
2012-03-08 16:35                                           ` Eric W. Biederman
2012-03-09  9:31                                             ` Fernando Luis Vázquez Cao
2012-03-09  9:51                                               ` [PATCH 1/3] boot: fortify early_idt_handlers definition Fernando Luis Vázquez Cao
2012-03-09  9:55                                                 ` [PATCH 2/3] boot: ignore early NMIs Fernando Luis Vázquez Cao
2012-03-09 10:01                                                   ` [PATCH 3/3] boot: add early NMI counter Fernando Luis Vázquez Cao
2012-03-09 20:52                                             ` [PATCH 1/2] boot: ignore early NMIs H. Peter Anvin
2012-03-12  5:43                                               ` Fernando Luis Vázquez Cao
2012-03-12  5:49                                                 ` H. Peter Anvin
2012-03-12  6:14                                                   ` Fernando Luis Vázquez Cao
2012-03-12 13:36                                                     ` Vivek Goyal
2012-03-12 19:02                                                       ` Eric W. Biederman
2012-03-12 19:58                                                         ` Vivek Goyal
2012-03-12 20:02                                                         ` H. Peter Anvin
2012-03-12 18:40                                                     ` H. Peter Anvin
2012-03-12 20:01                                                       ` Eric W. Biederman
2012-03-12 20:04                                                         ` H. Peter Anvin
2012-03-12 20:16                                                           ` H. Peter Anvin
2012-03-13  2:11                                                             ` Fernando Luis Vázquez Cao
2012-03-13 13:33                                                               ` Don Zickus
2012-03-15  0:43                                                                 ` Simon Horman
2012-03-13  1:43                                                       ` Fernando Luis Vázquez Cao
2012-03-12 14:41                                                   ` Don Zickus
2012-03-07 15:50                                     ` [tip:x86/debug] x86/kdump: No need to disable ioapic/ lapic in crash path Vivek Goyal
2012-03-07 18:27                                       ` Yinghai Lu
2012-03-08  1:29                                         ` Fernando Luis Vázquez Cao
2012-03-09  0:59                                     ` HATAYAMA Daisuke
2012-03-09  2:48                                       ` Eric W. Biederman
2012-02-12 11:12   ` Ingo Molnar
2012-02-13 15:28   ` Don Zickus
2012-02-13 16:52     ` Yinghai Lu
2012-02-13 22:12       ` Don Zickus
2012-02-13 22:51         ` Don Zickus
2012-02-16  2:53       ` Don Zickus
2012-02-16 18:43         ` Yinghai Lu
2012-02-16 21:41           ` Don Zickus

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20120216215603.GH9751@redhat.com \
    --to=dzickus@redhat.com \
    --cc=akpm@linux-foundation.org \
    --cc=ebiederm@xmission.com \
    --cc=hpa@zytor.com \
    --cc=kexec@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tip-commits@vger.kernel.org \
    --cc=mingo@elte.hu \
    --cc=mingo@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=torvalds@linux-foundation.org \
    --cc=vgoyal@redhat.com \
    --cc=yinghai@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).