Bug 1450317

Summary: "cpu-baseline" command doesn't deal with "cmt" fea-ture
Product: Red Hat Enterprise Linux 7 Reporter: Jing Qi <jinqi>
Component: libvirtAssignee: Jiri Denemark <jdenemar>
Status: CLOSED ERRATA QA Contact: Jing Qi <jinqi>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 7.4CC: agurenko, dyuan, rbalakri, xuzhang, yalzhang
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: libvirt-3.8.0-1.el7 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2018-04-10 10:43:32 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: 1199452    

Description Jing Qi 2017-05-12 09:02:47 UTC
Description of problem:
"cpu-baseline"  command doesn't deal with "cmt" feature 
and fail to start a domain which cpu part is generated by "cpu-baseline" .

Version-Release number of selected component (if applicable):
libvirt-3.2.0-4.el7.x86_64
qemu-kvm-rhev-2.9.0-3.el7.x86_64


How reproducible:

100%
Steps to Reproduce:

1. There are two cpu models and get the cpu part from "virsh capabilities"  to cpu.xml as below:
<cpu>
      <arch>x86_64</arch>
      <model>Broadwell</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='8' threads='2'/>
      <feature name='vme'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='dca'/>
      <feature name='osxsave'/>
      <feature name='f16c'/>
      <feature name='rdrand'/>
      <feature name='arat'/>
      <feature name='tsc_adjust'/>
      <feature name='cmt'/>
      <feature name='xsaveopt'/>
      <feature name='mbm_total'/>
      <feature name='mbm_local'/>
      <feature name='pdpe1gb'/>
      <feature name='abm'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>


<cpu>
      <arch>x86_64</arch>
      <model>Haswell-noTSX</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='18' threads='2'/>
      <feature name='vme'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='dca'/>
      <feature name='osxsave'/>
      <feature name='f16c'/>
      <feature name='rdrand'/>
      <feature name='arat'/>
      <feature name='tsc_adjust'/>
      <feature name='cmt'/>
      <feature name='xsaveopt'/>
      <feature name='pdpe1gb'/>
      <feature name='abm'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>

2. Use "Virsh cpu-baseline" command to get the baseline CPU part.
# virsh cpu-baseline cpu.xml
<cpu mode='custom' match='exact'>
  <model fallback='allow'>Haswell-noTSX</model>
  <vendor>Intel</vendor>
  <feature policy='require' name='vme'/>
  <feature policy='require' name='ds'/>
  <feature policy='require' name='acpi'/>
  <feature policy='require' name='ss'/>
  <feature policy='require' name='ht'/>
  <feature policy='require' name='tm'/>
  <feature policy='require' name='pbe'/>
  <feature policy='require' name='dtes64'/>
  <feature policy='require' name='monitor'/>
  <feature policy='require' name='ds_cpl'/>
  <feature policy='require' name='vmx'/>
  <feature policy='require' name='smx'/>
  <feature policy='require' name='est'/>
  <feature policy='require' name='tm2'/>
  <feature policy='require' name='xtpr'/>
  <feature policy='require' name='pdcm'/>
  <feature policy='require' name='dca'/>
  <feature policy='require' name='osxsave'/>
  <feature policy='require' name='f16c'/>
  <feature policy='require' name='rdrand'/>
  <feature policy='require' name='arat'/>
  <feature policy='require' name='tsc_adjust'/>
  <feature policy='require' name='cmt'/>
  <feature policy='require' name='xsaveopt'/>
  <feature policy='require' name='pdpe1gb'/>
  <feature policy='require' name='abm'/>
  <feature policy='require' name='invtsc'/>
</cpu>

3. 
Tried to use above part in the machine with Haswell-noTSX CPU model and the guest failed to start for below error:

[root@intel-brickland-04 images]# virsh start rhel7_1
error: Failed to start domain rhel7_1
error: internal error: process exited while connecting to monitor: 2017-05-12T08:07:53.701712Z qemu-kvm: -chardev pty,id=charserial0: char device redirected to /dev/pts/1 (label charserial0)
2017-05-12T08:07:53.706843Z qemu-kvm: can't apply global Haswell-noTSX-x86_64-cpu.cmt=on: Property '.cmt' not found

Actual results:
As in step3, fail to start a domain which cpu part is generated by "cpu-baseline"

Expected results:

Should succeed to start a domain which cpu part is generated by "cpu-baseline"

Additional info:

Comment 3 Jiri Denemark 2017-09-14 10:57:53 UTC
Patches sent upstream for review: https://www.redhat.com/archives/libvir-list/2017-September/msg00357.html

Comment 4 Jiri Denemark 2017-09-18 10:14:47 UTC
Fixed upstream by

commit 2ba32a86ddfa8992ade9d04c5661c1780781c09f
Refs: v3.7.0-90-g2ba32a86dd
Author:     Jiri Denemark <jdenemar>
AuthorDate: Wed Sep 13 17:28:48 2017 +0200
Commit:     Jiri Denemark <jdenemar>
CommitDate: Mon Sep 18 10:40:12 2017 +0200

    qemu: Filter CPU features returned by qemuConnectBaselineCPU

    The host CPU definitions reported in the capabilities XML may contain
    CPU features unknown to QEMU, but the result of virConnectBaselineCPU is
    supposed to be directly usable as a guest CPU definition and thus it
    should only contain features QEMU knows about.

    https://bugzilla.redhat.com/show_bug.cgi?id=1450317

    Signed-off-by: Jiri Denemark <jdenemar>

Comment 6 Jing Qi 2017-10-11 04:13:24 UTC
With qemu-kvm-rhev-2.10.0-1.el7.x86_64 and libvirt-3.8.0-1.el7.x86_64, using below cpu.xml as below, and use "virsh cpu-baseline cpu.xml" cmd,  can get a usable cpu set for two servers and "cmt" feature doesn't exist in the set.
 
cpu.xml
<cpu>
      <arch>x86_64</arch>
      <model>Broadwell</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='8' threads='2'/>
      <feature name='vme'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='dca'/>
      <feature name='osxsave'/>
      <feature name='f16c'/>
      <feature name='rdrand'/>
      <feature name='arat'/>
      <feature name='tsc_adjust'/>
      <feature name='cmt'/>
      <feature name='xsaveopt'/>
      <feature name='mbm_total'/>
      <feature name='mbm_local'/>
      <feature name='pdpe1gb'/>
      <feature name='abm'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>

<cpu>
      <arch>x86_64</arch>
      <model>Skylake-Client</model>
      <vendor>Intel</vendor>
      <topology sockets='1' cores='4' threads='2'/>
      <feature name='ds'/>
      <feature name='acpi'/>
      <feature name='ss'/>
      <feature name='ht'/>
      <feature name='tm'/>
      <feature name='pbe'/>
      <feature name='dtes64'/>
      <feature name='monitor'/>
      <feature name='ds_cpl'/>
      <feature name='vmx'/>
      <feature name='smx'/>
      <feature name='est'/>
      <feature name='tm2'/>
      <feature name='xtpr'/>
      <feature name='pdcm'/>
      <feature name='osxsave'/>
      <feature name='tsc_adjust'/>
      <feature name='clflushopt'/>
      <feature name='xsaves'/>
      <feature name='pdpe1gb'/>
      <feature name='invtsc'/>
      <pages unit='KiB' size='4'/>
      <pages unit='KiB' size='2048'/>
      <pages unit='KiB' size='1048576'/>
    </cpu>
        
# virsh cpu-baseline cpu1.xml
<cpu mode='custom' match='exact'>
  <model fallback='allow'>Skylake-Client</model>
  <vendor>Intel</vendor>
  <feature policy='require' name='ds'/>
  <feature policy='require' name='acpi'/>
  <feature policy='require' name='ss'/>
  <feature policy='require' name='ht'/>
  <feature policy='require' name='tm'/>
  <feature policy='require' name='pbe'/>
  <feature policy='require' name='dtes64'/>
  <feature policy='require' name='monitor'/>
  <feature policy='require' name='ds_cpl'/>
  <feature policy='require' name='vmx'/>
  <feature policy='require' name='smx'/>
  <feature policy='require' name='est'/>
  <feature policy='require' name='tm2'/>
  <feature policy='require' name='xtpr'/>
  <feature policy='require' name='pdcm'/>
  <feature policy='require' name='osxsave'/>
  <feature policy='require' name='tsc_adjust'/>
  <feature policy='require' name='pdpe1gb'/>
  <feature policy='require' name='invtsc'/>
  <feature policy='disable' name='mpx'/>
  <feature policy='disable' name='xsavec'/>
  <feature policy='disable' name='xgetbv1'/>
</cpu>


Use the above cpu set in a xml file and start the domain.
# virsh start generic
Domain generic started

Comment 10 errata-xmlrpc 2018-04-10 10:43:32 UTC
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://access.redhat.com/errata/RHEA-2018:0704