From: Don Zickus <dzickus@redhat.com>
To: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: linux-watchdog@vger.kernel.org, kexec@lists.infradead.org,
wim@iguana.be, LKML <linux-kernel@vger.kernel.org>,
vgoyal@redhat.com, dyoung@redhat.com, linux@roeck-us.net
Subject: Re: [PATCH v3] watchdog: Add hook for kicking in kdump path
Date: Thu, 18 Apr 2013 09:00:09 -0400 [thread overview]
Message-ID: <20130418130009.GH79013@redhat.com> (raw)
In-Reply-To: <87li8gaku0.fsf@xmission.com>
On Wed, Apr 17, 2013 at 02:49:59PM -0700, Eric W. Biederman wrote:
> Don Zickus <dzickus@redhat.com> writes:
>
> > A common problem with kdump is that during the boot up of the
> > second kernel, the hardware watchdog times out and reboots the
> > machine before a vmcore can be captured.
> >
> > Instead of tellling customers to disable their hardware watchdog
> > timers, I hacked up a hook to put in the kdump path that provides
> > one last kick before jumping into the second kernel.
> >
> > The assumption is the watchdog timeout is at least 10-30 seconds
> > long, enough to get the second kernel to userspace to kick the watchdog
> > again, if needed.
>
> Why not double the watchdog timeout? and/or pet the watchdog a little
> more frequently.
I am not sure if the watchdog timeouts can be doubled. I think Guenter
was saying some have a max of a couple seconds?? Petting a little more
frequently might be an option. Guenter can that be done with a softdog
option?
Cheers,
Don
next prev parent reply other threads:[~2013-04-18 13:00 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-17 21:19 [PATCH v3] watchdog: Add hook for kicking in kdump path Don Zickus
2013-04-17 21:33 ` Guenter Roeck
2013-04-17 21:49 ` Eric W. Biederman
2013-04-18 3:03 ` Guenter Roeck
2013-04-18 13:00 ` Don Zickus [this message]
2013-04-18 13:49 ` Guenter Roeck
2013-04-18 13:52 ` Don Zickus
2013-04-18 14:54 ` Guenter Roeck
2013-04-24 14:42 ` Don Zickus
2013-04-24 15:21 ` Guenter Roeck
2013-05-27 19:16 ` Wim Van Sebroeck
2013-05-28 1:10 ` Guenter Roeck
2013-05-30 20:37 ` Wim Van Sebroeck
2013-05-28 15:34 ` Guenter Roeck
2013-05-30 21:54 ` Wim Van Sebroeck
2013-04-18 16:35 ` Eric W. Biederman
2013-04-18 17:44 ` Don Zickus
2013-04-18 18:09 ` Eric W. Biederman
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