Re: [PATCH] watchdog: add a parameter for stop wdt before register

[Dave Young <dyoung@redhat.com>]

On 01/15/14 at 11:55am, Vivek Goyal wrote:
> On Wed, Jan 15, 2014 at 12:15:56PM +0000, One Thousand Gnomes wrote:
> > > watchdog and crash dump really conflicts to some degree, from the watchdog
> > > point of view it can reboot system whhen kdump kernel hangs. But from kdump
> > > point of view it want ensure saving the vmcore for later debugging.
> > > 
> > > Maybe we can only select only one in this case.
> > 
> > You want to be able to make a decision at runtime which to use.
> > 
> > > > - if it can be stopped, you can open and stop it
> > > 
> > > For the last one since crashing happens we have no chance to open and stop.
> > 
> > When you decide you need to set up to catch a core rather than just
> > crash you can open and stop the watchdog (if supported), and you can then
> > set up for a kdump and then at some point later if it crashes capture the
> > dump.
> 
> Disabling watchdog if kdump serice starts will not make many happy. If
> kernel hangs, we don't have a functionality to reboot it.
> 
> What about other idea of keeping watchdog interval long enough that new
> kernel can boot, driver can load and then new driver/user space can
> continue to kick the watchdog. And if second kernel hangs, watchdog will
> reboot the system.

I would agree this way.

Thanks
Dave