> -----Original Message----- > From: Vadim Rozenfeld [mailto:vrozenfe@xxxxxxxxxx] > Sent: Tuesday, September 05, 2017 2:33 PM > To: Gonglei (Arei); Paolo Bonzini > Cc: Hangaohuai; Yan Vugenfirer; qemu-devel@xxxxxxxxxx; > kvm@xxxxxxxxxxxxxxx; Radim Krcmar > Subject: Re: [Qemu-devel] [Help] Windows2012 as Guest 64+cores on KVM > Halts > > > > On 21/02/17 00:18, Gonglei (Arei) wrote: > >> > >> On 20/02/2017 12:54, Gonglei (Arei) wrote: > >>>> On 20/02/2017 10:19, Gonglei (Arei) wrote: > >>>>> Hi Paolo, > >>>>> > >>>>>> > >>>>>> On 16/02/2017 02:31, Gonglei (Arei) wrote: > >>>>>>> And the below patch works for me, I can support max 255 vcpus for > >>>> WS2012 > >>>>>>> with hyper-v enlightenments. > >>>>>>> > >>>>>>> diff --git a/target/i386/kvm.c b/target/i386/kvm.c > >>>>>>> index 27fd050..efe3cbc 100644 > >>>>>>> --- a/target/i386/kvm.c > >>>>>>> +++ b/target/i386/kvm.c > >>>>>>> @@ -772,7 +772,7 @@ int kvm_arch_init_vcpu(CPUState *cs) > >>>>>>> > >>>>>>> c = &cpuid_data.entries[cpuid_i++]; > >>>>>>> c->function = HYPERV_CPUID_IMPLEMENT_LIMITS; > >>>>>>> - c->eax = 0x40; > >>>>>>> + c->eax = -1; > >>>>>>> c->ebx = 0x40; > >>>>>>> > >>>>>>> kvm_base = KVM_CPUID_SIGNATURE_NEXT; > >>>>>> This needs to depend on the machine type, but apart from that I think > >>>>> I don't know why. Because the negative effects for this change don't > exist > >>>>> on current QEMU IIUC, and we don't have compatible problems for live > >>>> migration. > >>>> > >>>> CPUID should never change with the same machine type and command > line. > >>>> > >>> OK, then how do we add compat code for the CPUID change? It's not a > visible > >> property. > >> > >> You can add a new property, something like hv-cpuid-limits-eax. > >> > > Sounds good. Let me try. :) > > > > Thanks, > > -Gonglei > Hi Gonglei, > Any update on this issue? > > We've found that SVVP on WS2016 is passing successfully with the above > change > and more than 64 vCPUs defined. > > Vadim. Thanks for reminding me :) I'll send this patch this evening, and welcome to test it then. Regards, -Gonglei
