> -邮件原件-
> 发件人: Dr. David Alan Gilbert [mailto:dgilb...@redhat.com]
> 发送时间: 2018年4月12日 20:37
> 收件人: linzhecheng <linzhech...@huawei.com>; pbonz...@redhat.com
> 抄送: qemu-devel@nongnu.org; wangxin (U) <wangxinxin.w...@huawei.com>;
> Zhoujian (jay) <jianjay.z...@huawei.com>; quint...@redhat.com
> 主题: Re: [Qemu-devel] [Bug Report] vm paused after succeeding to migrate
>
> * linzhecheng (linzhech...@huawei.com) wrote:
> > Hi, all
> > I encounterd a bug when I try to migrate a windows vm.
> >
> > Enviroment information:
> > host A: cpu E5620(model WestmereEP without flag xsave) host B: cpu
> > E5-2643(model SandyBridgeEP with xsave)
> >
> > The reproduce steps is :
> > 1. Start a windows 2008 vm with -cpu host(which means host-passthrough).
> > 2. Migrate the vm to host B when cr4.OSXSAVE=0 (successfully).
> > 3. Vm runs on host B for a while so that cr4.OSXSAVE changes to 1.
> > 4. Then migrate the vm to host A (successfully), but vm was paused, and
> qemu printed log as followed:
>
> Remember that migrating using -cpu host across different CPU models is NOT
> expected to work.
>
> > KVM: entry failed, hardware error 0x8021
> >
> > If you're running a guest on an Intel machine without unrestricted
> > mode support, the failure can be most likely due to the guest entering
> > an invalid state for Intel VT. For example, the guest maybe running in
> > big real mode which is not supported on less recent Intel processors.
> >
> > EAX=019b3bb0 EBX=01a3ae80 ECX=01a61ce8 EDX=
> > ESI=01a62000 EDI= EBP= ESP=01718b20
> > EIP=0185d982 EFL=0286 [--S--P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES
> > = 9300 CS =f000 9b00
> > SS = 9300 DS =
> > 9300 FS = 9300 GS =
> > 9300
> > LDT= 8200
> > TR = 8b00
> > GDT=
> > IDT=
> > CR0=6010 CR2= CR3= CR4=
> > DR0= DR1= DR2=
> > DR3=
> > DR6=0ff0 DR7=0400
> > EFER=
> > Code=00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 <00>
> > 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> > 00 00 00 00 00 00
> >
> > I have found that problem happened when kvm_put_sregs returns err -
> 22(called by kvm_arch_put_registers(qemu)).
> > Because kvm_arch_vcpu_ioctl_set_sregs(kvm-mod) checked that
> guest_cpuid_has no X86_FEATURE_XSAVE but cr4.OSXSAVE=1.
> > So should we cancel migration when kvm_arch_put_registers returns error?
>
> It would seem good if we can make the migration fail there rather than hitting
> that KVM error.
> It looks like we need to do a bit of plumbing to convert the places that call
> it to
> return a bool rather than void.
I think we should return a int value of run_on_cpu which callback
run_on_cpu_func, but run_on_cpu_func is the prototype of many functions,
Is it overkill?
>
> Dave
>
> --
> Dr. David Alan Gilbert / dgilb...@redhat.com / Manchester, UK
