Re: [PATCH v2 4/4] KVM: Allow host IRQ sharing for passed-through PCI 2.3 devices

[Jan Kiszka <jan.kiszka@siemens.com>]

Am 02.11.2010 19:40, Jan Kiszka wrote:
>>>>> @@ -199,6 +343,13 @@ static void kvm_free_assigned_device(struct kvm *kvm,
>>>>>  
>>>>>  	pci_reset_function(assigned_dev->dev);
>>>>>  
>>>>> +	/*
>>>>> +	 * Unmask the IRQ at PCI level once the reset is done - the next user
>>>>> +	 * may not expect the IRQ being masked.
>>>>> +	 */
>>>>> +	if (assigned_dev->pci_2_3)
>>>>> +		pci_2_3_irq_unmask(assigned_dev->dev);
>>>>> +
>>>>
>>>> Doesn't pci_reset_function clear mask bit? It seems to ...
>>>
>>> I was left with non-functional devices for the host here if I was not
>>> doing this. Need to recheck, but I think it was required.
>>
>> Interesting. Could you check why please?
>>
> 
> Can't reproduce anymore. This was early code, maybe affected by some
> bits or buts that no longer exist.
> 
> Spec says it's cleared on reset, so I removed those lines now.
> 

Hmpf, it just happened again: Guest was using my ath9k, I killed the
guest, lspci says DisINTx+. Strange. Is anyone (qemu) restoring the
config space after the reset, bringing the disable bit back?

Jan

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