Re: [Qemu-devel] 答复: [BUG] Windows 7 got stuck easily while run PCMark10 application

[Paolo Bonzini]

On 01/12/2017 18:45, Gonglei (Arei) wrote:
> I also think it's windows bug, the problem is that it doesn't occur on
> xen platform.

It's a race, it may just be that RTC PIO is faster in Xen because it's
implemented in the hypervisor.

I will try reporting it to Microsoft.

Thanks,

Paolo

> Thanks,
> Gonglei
> *发件人：*Paolo Bonzini
> *收件人：*龚磊,张海亮,qemu-devel,Michael S. Tsirkin
> *抄送：*黄伟栋,王欣,谢祥有
> *时间：*2017-12-02 01:10:08
> *主题:*Re: [BUG] Windows 7 got stuck easily while run PCMark10 application
> 
> On 01/12/2017 08:08, Gonglei (Arei) wrote:
>> First write to 0x70, cmos_index = 0xc & 0x7f = 0xc
>>        CPU 0/KVM-15566 kvm_pio: pio_write at 0x70 size 1 count 1 val 0xc> 
>> Second write to 0x70, cmos_index = 0x86 & 0x7f = 0x6>        CPU 1/KVM-15567 
>> kvm_pio: pio_write at 0x70 size 1 count 1 val 0x86> vcpu0 read 0x6 because 
>> cmos_index is 0x6 now:>        CPU 0/KVM-15566 kvm_pio: pio_read at 0x71 
>> size 1 count 1 val 0x6> vcpu1
> read 0x6:>        CPU 1/KVM-15567 kvm_pio: pio_read at 0x71 size 1 count
> 1 val 0x6
> This seems to be a Windows bug.  The easiest workaround that I
> can think of is to clear the interrupts already when 0xc is written,
> without waiting for the read (because REG_C can only be read).
> 
> What do you think?
> 
> Thanks,
> 
> Paolo