Re: [PATCH] KVM: x86: Don't deliver PIC interrupts to disabled APICs - v2

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

Jan Kiszka wrote:
> Avi Kivity wrote:
>> Jan Kiszka wrote:
>>> [ taking Sheng's comments into account ]
>>>
>>> The logic of kvm_apic_accept_pic_intr has a minor, practically hardly
>>> relevant incorrectness: PIC interrupts are still delivered even if the
>>> APIC of VPU0 (BSP) is disabled. This does not comply with the Virtual
>>> Wire mode according to the Intel MP spec.
>>>   
>> This breaks Windows XP with the Standard PC HAL, so I am unapplying this
>> patch.
> 
> Hmm, this points to either an APIC setup or BIOS bug. To my
> understanding, the Standard PC HAL should not fiddle with the APIC, so
> what the BIOS leaves behind should counts. But I think I found no traces
> of APIC manipulation in rombios32.c.

Manipulation on UP systems. There is fiddling for SMP. But I will check
again.

Jan

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