From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59311) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dp7QZ-0005JY-Fk for qemu-devel@nongnu.org; Tue, 05 Sep 2017 02:33:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dp7QU-0000Y8-JY for qemu-devel@nongnu.org; Tue, 05 Sep 2017 02:33:39 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58032) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dp7QU-0000WO-Ai for qemu-devel@nongnu.org; Tue, 05 Sep 2017 02:33:34 -0400 References: <589C099A.9090605@huawei.com> <33183CC9F5247A488A2544077AF19020DA1B4379@DGGEMA505-MBX.china.huawei.com> <105e5774-38c3-0683-ca08-64f6ed53c643@redhat.com> <33183CC9F5247A488A2544077AF19020DA1B6988@DGGEMA505-MBX.china.huawei.com> <2127602137.20489688.1486827559449.JavaMail.zimbra@redhat.com> <1486980300.17184.28.camel@redhat.com> <33183CC9F5247A488A2544077AF19020DA1BD1CA@DGGEMA505-MBX.china.huawei.com> <33183CC9F5247A488A2544077AF19020DA1C13C3@DGGEMA505-MBX.china.huawei.com> <43632326-97a1-1f60-39f4-1044cd596b66@redhat.com> <33183CC9F5247A488A2544077AF19020DA1C1608@DGGEMA505-MBX.china.huawei.com> <33183CC9F5247A488A2544077AF19020DA1C16C5@DGGEMA505-MBX.china.huawei.com> From: Vadim Rozenfeld Message-ID: Date: Tue, 5 Sep 2017 16:33:23 +1000 MIME-Version: 1.0 In-Reply-To: <33183CC9F5247A488A2544077AF19020DA1C16C5@DGGEMA505-MBX.china.huawei.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [Help] Windows2012 as Guest 64+cores on KVM Halts List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Gonglei (Arei)" , Paolo Bonzini Cc: Hangaohuai , Yan Vugenfirer , "qemu-devel@nongnu.org" , "kvm@vger.kernel.org" , Radim Krcmar 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.