[PATCH v3] watchdog: Add hook for kicking in kdump path

Don Zickus dzickus at redhat.com
Thu Apr 18 09:00:09 EDT 2013

On Wed, Apr 17, 2013 at 02:49:59PM -0700, Eric W. Biederman wrote:
> Don Zickus <dzickus at 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


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