Re: [PATCH 1/3] xen/domain: Reorder trivial initialisation in early domain_create()

[Jan Beulich <jbeulich@xxxxxxxx>]

On 22.12.2020 11:24, Andrew Cooper wrote:
> On 22/12/2020 10:10, Jan Beulich wrote:
>> On 21.12.2020 19:14, Andrew Cooper wrote:
>>> --- a/xen/common/domain.c
>>> +++ b/xen/common/domain.c
>>> @@ -391,25 +391,7 @@ struct domain *domain_create(domid_t domid,
>>>  
>>>      TRACE_1D(TRC_DOM0_DOM_ADD, d->domain_id);
>>>  
>>> -    /*
>>> -     * Allocate d->vcpu[] and set ->max_vcpus up early.  Various per-domain
>>> -     * resources want to be sized based on max_vcpus.
>>> -     */
>>> -    if ( !is_system_domain(d) )
>>> -    {
>>> -        err = -ENOMEM;
>>> -        d->vcpu = xzalloc_array(struct vcpu *, config->max_vcpus);
>>> -        if ( !d->vcpu )
>>> -            goto fail;
>>> -
>>> -        d->max_vcpus = config->max_vcpus;
>>> -    }
>>> -
>>> -    lock_profile_register_struct(LOCKPROF_TYPE_PERDOM, d, domid);
>> Wouldn't this also count as "trivial initialization", and hence while
>> moving want to at least be placed ...
>>
>>> -    if ( (err = xsm_alloc_security_domain(d)) != 0 )
>>> -        goto fail;
>>> -
>>> +    /* Trivial initialisation. */
>>>      atomic_set(&d->refcnt, 1);
>>>      RCU_READ_LOCK_INIT(&d->rcu_lock);
>>>      spin_lock_init_prof(d, domain_lock);
>>> @@ -434,6 +416,27 @@ struct domain *domain_create(domid_t domid,
>>>      INIT_LIST_HEAD(&d->pdev_list);
>>>  #endif
>>>  
>>> +    /* All error paths can depend on the above setup. */
>> ... ahead of this comment?
> 
> Can do.

At which point

Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>

Jan