Re: [Qemu-ppc] [PATCH 4/4] Enable kvm emulated watchdog

[Bhushan Bharat-R65777]

> -----Original Message-----
> From: Wood Scott-B07421
> Sent: Friday, August 03, 2012 2:02 AM
> To: Bhushan Bharat-R65777
> Cc: Wood Scott-B07421; Alexander Graf; address@hidden List; kvm-
> address@hidden; qemu-devel qemu-devel; KVM list
> Subject: Re: [PATCH 4/4] Enable kvm emulated watchdog
> 
> On 08/02/2012 10:56 AM, Bhushan Bharat-R65777 wrote:
> >
> >
> >> -----Original Message-----
> >> From: Wood Scott-B07421
> >> Sent: Wednesday, August 01, 2012 11:31 PM
> >> To: Bhushan Bharat-R65777
> >> Cc: Alexander Graf; address@hidden List;
> >> address@hidden; qemu- devel qemu-devel; KVM list
> >> Subject: Re: [PATCH 4/4] Enable kvm emulated watchdog
> >>
> >> On 08/01/2012 12:27 PM, Bhushan Bharat-R65777 wrote:
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: Alexander Graf [mailto:address@hidden
> >>>> Sent: Wednesday, August 01, 2012 7:57 AM
> >>>> To: Bhushan Bharat-R65777
> >>>> Cc: address@hidden List; address@hidden; Bhushan
> >>>> Bharat-R65777; qemu-devel qemu-devel; KVM list
> >>>> Subject: Re: [PATCH 4/4] Enable kvm emulated watchdog
> >>>>
> >>>>
> >>>> On 20.07.2012, at 07:23, Bharat Bhushan wrote:
> >>>>> @@ -384,6 +437,15 @@ int kvm_arch_init_vcpu(CPUPPCState *cenv)
> >>>>>         return ret;
> >>>>>     }
> >>>>>
> >>>>> +    if (enable_watchdog_support) {
> >>>>> +        ret = kvm_watchdog_enable(cenv);
> >>>>
> >>>> Do you think this is a good idea? Why would real hardware not
> >>>> implement a watchdog just because the user didn't select an action?
> >>>
> >>> If there is no watchdog action then why we want to run watchdog timer?
> >>
> >> On real hardware, if software sets WRC to a non-zero value, the
> >> watchdog action is a system reset.  The user doesn't have to do anything
> special.
> >
> > Scott, maybe I misunderstood you comment, did not you commented to
> > enable kvm watchdog if there is watchdog action provided by use.
> 
> I changed my mind. :-)
> 
> The main difference between the user specifically asking for an action of 
> system
> reset, and the user not asking for anything, is that only in the former case
> should we error out if watchdog functionality isn't available -- but if it's a
> pain to distinguish, don't error out in either case.

:-) ..  ok 

-Bharat

> 
> -Scott