Re: [Xen-devel] [PATCH v4 08/15] pvh/acpi: Handle ACPI accesses for PVH guests

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 06.12.16 at 17:37, <boris.ostrovsky@xxxxxxxxxx> wrote:
> On 12/06/2016 09:34 AM, Jan Beulich wrote:
>>>>> On 29.11.16 at 16:33, <boris.ostrovsky@xxxxxxxxxx> wrote:
>>> --- a/xen/common/domctl.c
>>> +++ b/xen/common/domctl.c
>>> @@ -651,6 +651,11 @@ long do_domctl(XEN_GUEST_HANDLE_PARAM(xen_domctl_t) 
>>> u_domctl)
>>>                  goto maxvcpu_out;
>>>          }
>>>  
>>> +        d->avail_vcpus = xzalloc_array(unsigned long,
>>> +                                       BITS_TO_LONGS(d->max_vcpus));
>>> +        if ( !d->avail_vcpus )
>>> +            goto maxvcpu_out;
>> Considering this isn't being touched outside of
>> acpi_access_common(), how come you get away without setting
>> the bits for the vCPU-s online when the guest starts?
> 
> The AML code, which is the only reader of the map, is only executed
> after the map has been updated (i.e. the SCI has been sent). But I
> probably should have the toolstack initialize it when building the guest.

Thanks - that'll prevent this becoming a latent bug should some
other consumer of the map appear.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel