Bug 1320066
| Summary: | Qemu should not report error when cmdline set threads=2 in Intel host | ||||||
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| Product: | Red Hat Enterprise Linux 6 | Reporter: | weliao <weliao> | ||||
| Component: | qemu-kvm | Assignee: | Wei Huang (AMD) <wehuang> | ||||
| Status: | CLOSED ERRATA | QA Contact: | Virtualization Bugs <virt-bugs> | ||||
| Severity: | unspecified | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | 6.8 | CC: | ailan, chayang, hhuang, juzhang, mkenneth, rbalakri, virt-maint, wehuang, wei, weliao, yiwei, yuhuang, zhguo | ||||
| Target Milestone: | rc | Keywords: | Regression | ||||
| Target Release: | --- | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | qemu-kvm-0.12.1.2-2.495.el6 | Doc Type: | If docs needed, set a value | ||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2017-03-21 09:37:24 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: | 1359965 | ||||||
| Attachments: |
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Description
weliao
2016-03-22 09:15:43 UTC
Hi,Wei Seems this bug because fixed Bug 1292678 - Qemu should report error when cmdline set threads=2 in amd host , Can you check it? and on rhel7.2 no this issue. thanks Wei I can reproduce this bug on Intel box. However I think this isn't a bug from the instrumentation I did with QEMU 6.8. Here are the findings: 1) The problem was introduced by commit 50d095912. The related code is in pc_new_cpu() of hw/pc.c file. 2) IS_INTEL_CPU(env) is TRUE, implying that QEMU believes guest is an AMD CPU. 3) I instrumented cpu_x86_register() of target-i386/cpuid.c file. When no -cpu is specified, cpu_model name is "cpu64-rhel6". So by default qemu-kvm-6.8 uses "cpu64-rhel6" as the CPU model when nothing is specified. According to target-i386/cpuid.c, "cpu64-rhel6" is based on AMD CPU model. From the data collected above, I think this warning msg is legit because AMD CPU doesn't support HyperThreading. -Wei Is it a common usage case not to specify "-cpu"? I am trying to understand how annoying this warning message is. (In reply to Wei Huang from comment #5) > Is it a common usage case not to specify "-cpu"? I am trying to understand > how annoying this warning message is. Hi Wei, I personally think it's no common scenario. However, 2 concerns. 1. Seems this is regression issue according to comment0 2. It's strange that the qemu-kvm promotes message like "AMD CPU doesn't support ..." but the qemu runs on Intel host. Best Regards, Junyi Created attachment 1140266 [details]
patch
This issue is indeed a regression. I have created a patch to fix the problem. Fix included in qemu-kvm-0.12.1.2-2.495.el6 Reproduce proceduce
Host version:
kernel-2.6.32-642.el6.x86_64
qemu-kvm-0.12.1.2-2.490.el6.x86_64
Steps to Reproduce:
1./usr/libexec/qemu-kvm -name win10 -m 6G -smp 2,threads=2,cores=1,sockets=1
qemu-kvm: AMD CPU doesn't support hyperthreading. Please configure -smp options properly.
VNC server running on `::1:5900'
Actual results:
report error:
qemu-kvm: AMD CPU doesn't support hyperthreading. Please configure -smp options properly.
-------------------------------------------
Verify this bug
Host version:
kernel-2.6.32-642.el6.x86_64
qemu-kvm-0.12.1.2-2.495.el6.x86_64
Test steps:
1./usr/libexec/qemu-kvm -name win10 -m 6G -smp 2,threads=2,cores=1,sockets=1
VNC server running on `::1:5900'
Test results:
not report this error.
Conclusion：
According to result above,this bug has been fixed.
Additional info:
My machine:
model name : Intel(R) Core(TM) i7-2600 CPU @ 3.40GHz
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHSA-2017-0621.html |