Re: [PATCH 1/2] KVM: provide irq_unsafe kvm_guest_{enter|exit}

[Christian Borntraeger <borntraeger@de.ibm.com>]

Am 30.04.2015 um 14:02 schrieb Christian Borntraeger:
> Am 30.04.2015 um 14:01 schrieb Christian Borntraeger:
>> Am 30.04.2015 um 13:50 schrieb Paolo Bonzini:
>>>
>>>
>>> On 30/04/2015 13:43, Christian Borntraeger wrote:
>>>> +/* must be called with irqs disabled */
>>>> +static inline void __kvm_guest_enter(void)
>>>>  {
>>>> -	unsigned long flags;
>>>> -
>>>> -	BUG_ON(preemptible());
>>>
>>> Please keep the BUG_ON() in kvm_guest_enter.  Otherwise looks good, thanks!
> 
> Ah, you mean have the BUG_ON in the non underscore version? Yes, makes sense.

Hmmm, too quick.
the BUG_ON was there to make sure that rcu_virt_note_context_switch is safe.
The reworked code pulls the rcu_virt_note_context_switch within the irq_save
section so we no longer need this BUG_ON, no?

Christian