Re: [PATCH RFC] hvm: Allow triple fault to imply crash rather than reboot

[Andrew Cooper <andrew.cooper3@citrix.com>]

On 04/02/13 14:46, Jan Beulich wrote:
>>>> On 04.02.13 at 15:25, Andrew Cooper <andrew.cooper3@citrix.com> wrote:
>> While the triple fault action on native hardware will result in a system
>> reset, any modern operating system can and will make use of less violent
>> reboot methods.  As a result, the most likely cause of a triple fault is a
>> fatal software bug.
>>
>> This patch allows the toolstack to indicate that a triple fault should mean 
>> a
>> crash rather than a reboot.  The default of reboot still remains the same.
> Makes sense to me; minor nits below (no need to resend just
> because of that, but would be nice to be addressed if you had
> to rev the patch anyway).
>
>> --- a/xen/arch/x86/hvm/hvm.c
>> +++ b/xen/arch/x86/hvm/hvm.c
>> @@ -1233,9 +1233,14 @@ void hvm_hlt(unsigned long rflags)
>>  void hvm_triple_fault(void)
>>  {
>>      struct vcpu *v = current;
>> +    struct domain * d = v->domain;
> Stray blank.

Space between * and d ?

>
>> +    u8 reason = d->arch.hvm_domain.params[HVM_PARAM_TRIPLE_FAULT_CRASH]
>> +        ? SHUTDOWN_crash : SHUTDOWN_reboot;
>> +
>>      gdprintk(XENLOG_INFO, "Triple fault on VCPU%d - "
>> -             "invoking HVM system reset.\n", v->vcpu_id);
>> -    domain_shutdown(v->domain, SHUTDOWN_reboot);
>> +             "invoking HVM system %s.\n", v->vcpu_id,
>> +             reason == SHUTDOWN_crash ? "crash" : "reboot");
>> +    domain_shutdown(v->domain, reason);
> So you have d cached in a local variable now, yet you still use
> v->domain here?

Doh - missed that.

>
> Also, I'd prefer for the message to continue to say "reset".
>
> Jan
>
Ok - I will respin and send as non-rfc.