Bug 821581
| Summary: | should fail to boot a guest with SandyBridge/Westmere/Nehalem/Penryn/Conroe model on the Opteron_G4 host | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Sibiao Luo <sluo> |
| Component: | qemu-kvm | Assignee: | Eduardo Habkost <ehabkost> |
| Status: | CLOSED CURRENTRELEASE | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 7.0 | CC: | acathrow, areis, bcao, bsarathy, chayang, ehabkost, flang, hhuang, huding, juzhang, michen, mkenneth, qzhang, shuang, sluo, virt-maint, wdai, xfu |
| Target Milestone: | pre-dev-freeze | Keywords: | Reopened |
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | upstream qemu-1.4.0 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2014-06-13 11:16:51 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 833129 | ||
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Description
Sibiao Luo
2012-05-15 02:21:02 UTC
Not very sure this bug is duplicated to the following bug. FYI Bug 692374 - -cpu enforce with wrong cpu flags does not cause qemu-kvm process quit *** This bug has been marked as a duplicate of bug 692374 *** hit the same problem on Opteron_G5 host.Boot a guest with /Westmere/Nehalem/Penryn/Conroe model on the Opteron_G5 host ,guest can be successfully boot without any warning prompts. version: # uname -r 2.6.32-339.el6.x86_64 # rpm -q qemu-kvm qemu-kvm-0.12.1.2-2.334.el6.x86_64 host: # cat /proc/cpuinfo processor : 0 vendor_id : AuthenticAMD cpu family : 21 model : 2 model name : AMD Eng Sample, 1S256146U8K54_35/25/20_2/8 stepping : 0 cpu MHz : 1400.000 cache size : 2048 KB physical id : 0 siblings : 8 core id : 0 cpu cores : 4 apicid : 16 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 13 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nonstop_tsc extd_apicid aperfmperf pni pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs xop skinit wdt lwp fma4 tce nodeid_msr tbm topoext perfctr_core cpb npt lbrv svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter pfthreshold bmi1 bogomips : 4987.26 TLB size : 1536 4K pages clflush size : 64 cache_alignment : 64 address sizes : 48 bits physical, 48 bits virtual power management: ts ttp tm 100mhzsteps hwpstate cpb eff_freq_ro steps: 1.boot a guest with Westmere/Nehalem/Penryn/Conroe model on Opteron_G5 host. eg: # <qemu-kvm-cmd> -cpu Westmere,enforce ... 2. 3. results: guest boot successfully , without any warning prompts addinfo:but if boot guest with "-cpu SandyBridge,enforce" on Opteron_G5 host,will prompt: #/usr/libexec/qemu-kvm ...... -serial unix:/tmp/tty0,server,nowait -global PIIX4_PM.disable_s3=0 -global PIIX4_PM.disable_s4=0 -usbdevice tablet warning: host cpuid 0000_0001:ecx lacks requested flag 'tsc-deadline' [0x01000000] Unable to support requested x86 CPU definition --->then qemu quit The -cpu enforce bugs should be fixed on QEMU 1.4.0, see bug 822616. But please note that it is not true that the Intel models should always fail to start on AMD CPUs. If the features defined in a CPU model are a subset of the models available on the host, -cpu enforce won't abort. -cpu enforce doesn't check the CPU vendor at all, it just checks if all the requested features are supported by the host. Verify this bug using the following version: qemu-kvm-1.5.3-40.el7.x86_64 kernel-3.10.0-64.el7.x86_64 Steps of verification: 1. boot a SandyBridge guest on Opteron_G5 host # /usr/libexec/qemu-kvm -M pc -cpu SandyBridge,enforce ... 2. boot a Westmere guest on Opteron_G5 host # /usr/libexec/qemu-kvm -M pc -cpu Westmere,enforce ... 3. 1. boot a Nehalem guest on Opteron_G5 host # /usr/libexec/qemu-kvm -M pc -cpu Nehalem,enforce ... 4. 1. boot a Penryn guest on Opteron_G5 host # /usr/libexec/qemu-kvm -M pc -cpu Penryn,enforce ... 5. 1. boot a Conroe guest on Opteron_G5 host # /usr/libexec/qemu-kvm -M pc -cpu Conroe,enforce ... Actual results: 1. After step1, SandyBrdige guest cannot boot and qemu-kvm quits with the error info: (qemu) warning: host doesn't support requested feature: CPUID.01H:ECX.tsc-deadline [bit 24] warning: host doesn't support requested feature: CPUID.80000001H:EDX.rdtscp [bit 27] qemu-kvm: Host's CPU doesn't support requested features 2. After step2, 3, 4, 5, Westmere/Nehalem/Penryn/Conroe guest can boot. Hi, Eduardo, I have a question, Westmere and SandyBrdige models have a flag "x2apic" and I check "/proc/cpuinfo" of Opteron_G5 host, there is not "x2apic". Why Westmere guest can boot on Opteron_G5 host, and not checking this flag "x2apic"? Look forward to your answer, thanks a lot. Best regards Huiqing x2apic is emulated by KVM, it doesn't require host CPU support. qemu-kvm should only abort if there is any feature on the CPU model that can't be supported by the host. qemu-kvm doesn't care about the CPU vendor ID at all. See comment #8. Opteron_G5 hosts seem to have all the features required by Westmere, Nehalem, Penryn, and Conroe, so it is not aborting. This request was resolved in Red Hat Enterprise Linux 7.0. Contact your manager or support representative in case you have further questions about the request. |