Bug 647125
| Summary: | /proc/cpuinfo doesn't show pbe although it's supported by CPU | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 5 | Reporter: | Alex Jia <ajia> |
| Component: | kvm | Assignee: | john cooper <john.cooper> |
| Status: | CLOSED NOTABUG | QA Contact: | Virtualization Bugs <virt-bugs> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 5.6 | CC: | clalance, drjones, eblake, jdenemar, llim, mkenneth, nobody, prarit, shu, virt-maint, xen-maint |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | Unspecified | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-03-21 23:07:56 UTC | Type: | --- |
| 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: | 580948 | ||
cpu-compare works as expected. The host CPU it compares cpu.xml with is the one from virsh capabilities. So if you take <cpu> element from capabilities and cpu-compare it, the result must be they are identical. So what you are reporting instead is that virsh capabilities mentions 'pbe' flag while you don't see that in /proc/cpuinfo. I'm pretty confident that's because RHEL-5 kernel doesn't advertise it for some reason. But I won't close this bz as NOTABUG yet. I'll first check if I'm really right. Tested on my machine... /proc/cpuinfo: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm x86info: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflsh ds acpi mmx fxsr sse sse2 ss ht tm pbe sse3 monitor ds-cpl vmx est tm2 ssse3 cx16 xTPR dca I just found this bug. It appears to be kvm, not xen, so I'm sending it over there for those guys to resolve the mismatch of cpu flag visibility. Host:RHEL5.6-x86-64
kernel-2.6.18-237.el5
kvm-83-224.el5
libvirt-0.8.2-15.el5
Steps to reproduce:
1. # cat /proc/cpuinfo | grep pbe
output:nothing
2. # virsh capabilities | grep pbe
output:<feature name='pbe'/>
3. # x86info | grep pbe
output: ... sse2 ss ht tm pbe sse3 monitor ds-cpl vmx ...
PS: There is pbe in /proc/cpuinfo with RHEL6.0-x86-64/kernel-2.6.32-94.el6.x86_64 on the same pc.
Closing as not a bug as I don't find justification to expose this flag to a guest. If a case can be made otherwise, feel free to reopen. |
Description of problem: Host cpu flags don't exist 'pbe' feature name on rhel5.6 beta with intel x86_64 arch, but virsh cpu-compare still match it and thinks it is identical to host cpu. Version-Release number of selected component (if applicable): # uname -r 2.6.18-225.el5 # cat /etc/redhat-release Red Hat Enterprise Linux Server release 5.6 Beta (Tikanga) # rpm -qa | grep libvirt libvirt-0.8.2-6.el5 libvirt-0.8.2-6.el5 libvirt-python-0.8.2-6.el5 libvirt-cim-0.5.8-3.el5 # rpm -q kvm kvm-83-200.el5 How reproducible: always Steps to Reproduce: 1. Using virsh capabilities to get <cpu> ... </cpu> block xml and save to a file cpu.xml 2. Using virsh cpu-compare cpu.xml to match it Actual results: # virsh capabilities <capabilities> <host> <uuid>44ee8208-c1e7-2d88-975a-35148d762a47</uuid> <cpu> <arch>x86_64</arch> <model>core2duo</model> <topology sockets='1' cores='2' threads='1'/> <feature name='lahf_lm'/> <feature name='xtpr'/> <feature name='cx16'/> <feature name='tm2'/> <feature name='est'/> <feature name='vmx'/> <feature name='ds_cpl'/> <feature name='pbe'/> <feature name='tm'/> <feature name='ht'/> <feature name='ss'/> <feature name='acpi'/> <feature name='ds'/> </cpu> ...... # cat cpu.xml <cpu> <arch>x86_64</arch> <model>core2duo</model> <topology sockets='1' cores='2' threads='1'/> <feature name='lahf_lm'/> <feature name='xtpr'/> <feature name='cx16'/> <feature name='tm2'/> <feature name='est'/> <feature name='vmx'/> <feature name='ds_cpl'/> <feature name='pbe'/> <feature name='tm'/> <feature name='ht'/> <feature name='ss'/> <feature name='acpi'/> <feature name='ds'/> </cpu> # virsh cpu-compare cpu.xml CPU described in cpu.xml is identical to host CPU # grep 'pbe' /proc/cpuinfo;echo $? 1 Expected results: fix it Additional info: # cat /proc/cpuinfo | grep flags | head -1 flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm syscall nx lm constant_tsc pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr lahf_lm # cat /usr/share/libvirt/cpu_map.xml <cpus> <arch name='x86'> <!-- standard features, EDX --> ...... <feature name='pbe'> <!-- CPUID_PBE --> <cpuid function='0x00000001' edx='0x80000000'/> </feature> ......