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

Guenter Roeck linux at roeck-us.net
Wed Apr 24 11:21:42 EDT 2013


On Wed, Apr 24, 2013 at 10:42:26AM -0400, Don Zickus wrote:
> On Thu, Apr 18, 2013 at 07:54:13AM -0700, Guenter Roeck wrote:
> > > No, that will probably work.  It is my misunderstanding.  Is there a
> > > common way to check the timeout length and the ping frequency?
> > > 
> > Usually it is configured in /etc/watchdog.conf if the watchdog package
> > is installed. The standard ping interval is "interval", the timeout is
> > "watchdog-timeout". See "man watchdog.conf" for details.
> > 
> > Minimum and maximum values for a given watchdog driver are not exported
> > to user space, so you would have to look into the driver sources to find
> > out what they are.
> 
> Hi Guenter,
> 
> Is there an easy way to determine which driver is loaded for each
> /dev/watchdogN device (from a script perspective).
> 
> Basically, I wanted to determine the module that needs to be included in
> the kdump initrd image.
> 
Sometimes. For example, the iTCO_wdt driver has an entry in /sys/devices, and
/sys/class/watchdog/watchdogX/device points to it. That is not always the case,
howewver. In my system, for example, the MEI watchdog is active, but there is
nothing I can find that would give me an indication that /dev/watchdog0 actually
points to the MEI watchdog driver.

Of course I might be missing something, and there might be some other means
to identify the driver from userspace. Would be great, actually, as I am having
the same problem.

Guenter



More information about the kexec mailing list