> -----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 0x80000021 > > > > 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=00000000 > > ESI=01a62000 EDI=00000000 EBP=00000000 ESP=01718b20 > > EIP=0185d982 EFL=00000286 [--S--P-] CPL=0 II=0 A20=1 SMM=0 HLT=0 ES > > =0000 00000000 0000ffff 00009300 CS =f000 ffff0000 0000ffff 00009b00 > > SS =0000 00000000 0000ffff 00009300 DS =0000 00000000 0000ffff > > 00009300 FS =0000 00000000 0000ffff 00009300 GS =0000 00000000 > > 0000ffff 00009300 > > LDT=0000 00000000 0000ffff 00008200 > > TR =0000 00000000 0000ffff 00008b00 > > GDT= 00000000 0000ffff > > IDT= 00000000 0000ffff > > CR0=60000010 CR2=00000000 CR3=00000000 CR4=00000000 > > DR0=0000000000000000 DR1=0000000000000000 DR2=0000000000000000 > > DR3=0000000000000000 > > DR6=00000000ffff0ff0 DR7=0000000000000400 > > EFER=0000000000000000 > > 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
