On 10.06.2024 11:10, Petr Beneš wrote:
> On Mon, Jun 10, 2024 at 9:30 AM Jan Beulich <jbeul...@suse.com> wrote:
>>
>> On 09.06.2024 01:06, Petr Beneš wrote:
>>> On Thu, Jun 6, 2024 at 9:24 AM Jan Beulich <jbeul...@suse.com> wrote:
>>>>> @@ -122,7 +131,12 @@ int p2m_init_altp2m(struct domain *d)
>>>>> struct p2m_domain *hostp2m = p2m_get_hostp2m(d);
>>>>>
>>>>> mm_lock_init(&d->arch.altp2m_list_lock);
>>>>> - for ( i = 0; i < MAX_ALTP2M; i++ )
>>>>> + d->arch.altp2m_p2m = xzalloc_array(struct p2m_domain *,
>>>>> d->nr_altp2m);
>>>>> +
>>>>> + if ( !d->arch.altp2m_p2m )
>>>>> + return -ENOMEM;
>>>>
>>>> This isn't really needed, is it? Both ...
>>>>
>>>>> + for ( i = 0; i < d->nr_altp2m; i++ )
>>>>
>>>> ... this and ...
>>>>
>>>>> {
>>>>> d->arch.altp2m_p2m[i] = p2m = p2m_init_one(d);
>>>>> if ( p2m == NULL )
>>>>> @@ -143,7 +157,10 @@ void p2m_teardown_altp2m(struct domain *d)
>>>>> unsigned int i;
>>>>> struct p2m_domain *p2m;
>>>>>
>>>>> - for ( i = 0; i < MAX_ALTP2M; i++ )
>>>>> + if ( !d->arch.altp2m_p2m )
>>>>> + return;
>>
>> I'm sorry, the question was meant to be on this if() instead.
>>
>>>>> + for ( i = 0; i < d->nr_altp2m; i++ )
>>>>> {
>>>>> if ( !d->arch.altp2m_p2m[i] )
>>>>> continue;
>>>>> @@ -151,6 +168,8 @@ void p2m_teardown_altp2m(struct domain *d)
>>>>> d->arch.altp2m_p2m[i] = NULL;
>>>>> p2m_free_one(p2m);
>>>>> }
>>>>> +
>>>>> + XFREE(d->arch.altp2m_p2m);
>>>>> }
>>>>
>>>> ... this ought to be fine without?
>>>
>>> Could you, please, elaborate? I honestly don't know what you mean here
>>> (by "this isn't needed").
>>
>> I hope the above correction is enough?
>
> I'm sorry, but not really? I feel like I'm blind but I can't see
> anything I could remove without causing (or risking) crash.
The loop is going to do nothing when d->nr_altp2m == 0, and the XFREE() is
going to do nothing when d->arch.altp2m_p2m == NULL. Hence what does the
if() guard against? IOW what possible crashes are you seeing that I don't
see?
Jan
