From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: Re: [edk2] KVM: MTRR: fix memory type handling if MTRR is completely disabled Date: Thu, 15 Oct 2015 14:41:50 +0800 Message-ID: <561F4AAE.3060204@linux.intel.com> References: <55FBDB6D.4040207@gmail.com> <55FBE248.4010809@redhat.com> <55FC4E6F.8030104@gmail.com> <55FF7095.5060106@linux.intel.com> <55FF7C41.7070400@linux.intel.com> <560D3F31.5000703@gmail.com> <560D40C2.5080205@redhat.com> <560E96D8.9080007@gmail.com> <561DD2EC.5040800@linux.intel.com> <561E0655.8080508@gmail.com> <561E1121.7030502@linux.intel.com> <561E1329.5080109@linux.intel.com> <561E9A36.3080302@gmail.com> <561F2952.5060300@linux.intel.com> <561F4589.5050609@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Cc: edk2-devel@ml01.01.org To: Janusz , Paolo Bonzini , Wanpeng Li , Laszlo Ersek , kvm@vger.kernel.org Return-path: Received: from mga02.intel.com ([134.134.136.20]:8538 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753384AbbJOGsN (ORCPT ); Thu, 15 Oct 2015 02:48:13 -0400 In-Reply-To: <561F4589.5050609@gmail.com> Sender: kvm-owner@vger.kernel.org List-ID: On 10/15/2015 02:19 PM, Janusz wrote: > W dniu 15.10.2015 o 06:19, Xiao Guangrong pisze: >> >> >> >> Well, the bug may be not in KVM. When this bug happened, i saw OVMF >> only checked 1 CPU out, there is the log from OVMF's debug input: >> >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCD >> Flushing GCDs >> Detect CPU count: 1 >> >> So that the startup code has been freed however the APs are still >> running, >> i think that why we saw the vCPUs executed on unexpected address. >> >> After digging into OVMF's code, i noticed that BSP CPU waits for APs >> for a fixed timer period, however, KVM recent changes require zap all >> mappings if CR0.CD is changed, that means the APs need more time to >> startup. >> >> After following changes to OVMF, the bug is completely gone on my side: >> >> --- a/UefiCpuPkg/CpuDxe/ApStartup.c >> +++ b/UefiCpuPkg/CpuDxe/ApStartup.c >> @@ -454,7 +454,9 @@ StartApsStackless ( >> // >> // Wait 100 milliseconds for APs to arrive at the ApEntryPoint routine >> // >> - MicroSecondDelay (100 * 1000); >> + MicroSecondDelay (10 * 100 * 1000); >> >> return EFI_SUCCESS; >> } >> >> Janusz, could you please check this instead? You can switch to your >> previous kernel to do this test. >> >> > Ok, now first time when I started VM I was able to start system > successfully. When I turned it off and started it again, it restarted my > vm at system boot couple of times. Sometimes I also get very high cpu > usage for no reason. Also, I get less fps in GTA 5 than in kernel 4.1, I > get something like 30-55, but on 4.1 I get all the time 60 fps. This is > my new log: https://bpaste.net/show/61a122ad7fe5 > Just confirm: the Qemu internal error did not appear any more, right?