Re: [UNTESTED] KVM: do not call kvm_set_irq from irq disabled section

[Avi Kivity <avi@redhat.com>]

On 04/23/2010 04:02 PM, Chris Lalancette wrote:
> On 04/23/2010 07:05 AM, Avi Kivity wrote:
>    
>> On 04/22/2010 10:55 PM, Gleb Natapov wrote:
>>      
>>>
>>>        
>>>>> What about converting PIC/IOAPIC mutexes into spinlocks?
>>>>>
>>>>>            
>>>> Works for me, but on large guests the spinning will be noticeable.
>>>> I believe.
>>>>
>>>>          
>>> For interrupts going through IOPIC, but we know this is not scalable
>>> anyway.
>>>
>>>        
>> Yes.  We also wanted to convert the ioapic/pic to spinlocks so we could
>> queue the interrupt from the PIT directly instead of using
>> KVM_REQ_PENDING_TIMER which keeps confusing me.  Chris Lalancette posted
>> a patchset for this a while back but it was never completed.
>>      
> Yeah, I'm sorry I never completed it.  It turns out that with the HPET
> changes that went in around the time I was looking at it, that set of
> patches wasn't really required to fix the problem I was seeing with kdump.
>
> That being said, if it's useful to somebody, I can repost the patches
> (though they are woefully out-of-date now).  Let me know if you want
> to see them again.
>    

Let's see if one of the alternatives works out.  I prefer to keep the 
critical sections short.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.