Bug 2029582

Summary:	[8.6] machine types: 6.2: Fix prefer_sockets
Product:	Red Hat Enterprise Linux 8	Reporter:	Dr. David Alan Gilbert <dgilbert>
Component:	qemu-kvm	Assignee:	Dr. David Alan Gilbert <dgilbert>
qemu-kvm sub component:	Machine Types	QA Contact:	liunana <nanliu>
Status:	CLOSED ERRATA	Docs Contact:
Severity:	medium
Priority:	medium	CC:	chayang, cohuck, coli, ddepaula, jinzhao, juzhang, nanliu, thuth, virt-maint
Version:	8.6
Target Milestone:	rc
Target Release:	8.6
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:	qemu-kvm-6.2.0-4.module+el8.6.0+13919+adb438db	Doc Type:	No Doc Update
Doc Text:		Story Points:	---
Clone Of:	2028623	Environment:
Last Closed:	2022-05-10 13:24:19 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:	2027716, 2028623
Bug Blocks:

Description Dr. David Alan Gilbert 2021-12-06 19:58:08 UTC

+++ This bug was initially created as a clone of Bug #2028623 +++

Description of problem:
cohuck spotted that I'd missed the prefer_sockets line in the machine option compatibility for the x86 machine types; it looks like th_huth nailed it for s390.
(We'll also need this on 8.6, so probably need it for Power and hmm aarch?)

Version-Release number of selected component (if applicable):
6.2 rebase

How reproducible:
100%

Steps to Reproduce:
1. start a guest with -smp 8
2. lscpu


Actual results:
    Core(s) per socket:  8
    Socket(s):           1

Expected results:
    Core(s) per socket:  1
    Socket(s):           8


Additional info:

Comment 1 Dr. David Alan Gilbert 2021-12-09 10:40:57 UTC

https://gitlab.com/redhat/rhel/src/qemu-kvm/qemu-kvm/-/merge_requests/86

Comment 2 liunana 2021-12-20 03:33:18 UTC

Could you help to set the ITR so that I can set the ITM? Thanks.



Best regards
Liu Nana

Comment 5 Danilo de Paula 2021-12-23 18:49:49 UTC

Hi David,


Can you please check that this changes are indeed fixed in the 8.6 branch?

Comment 9 Yanan Fu 2022-01-18 08:54:56 UTC

QE bot(pre verify): Set 'Verified:Tested,SanityOnly' as gating/tier1 test pass.

Comment 10 liunana 2022-01-24 15:26:20 UTC

Test Env:
    4.18.0-360.el8.x86_64
    qemu-kvm-6.2.0-4.module+el8.6.0+13930+1ccead3d.x86_64
    dell-per750-05.lab.eng.pek2.redhat.com
Guest: 4.18.0-359.el8.x86_64

Test steps:
   1. Boot guest with '-smp 8'
  2. lscpu inside guest.
# lscpu
CPU(s):              8
On-line CPU(s) list: 0-7
Thread(s) per core:  1
Core(s) per socket:  1
Socket(s):           8
BIOS Model name:     RHEL-8.5.0 PC (Q35 + ICH9, 2009)


  3. check 'pc' machine type, get the same results:
# lscpu
CPU(s):              8
On-line CPU(s) list: 0-7
Thread(s) per core:  1
Core(s) per socket:  1
Socket(s):           8
BIOS Model name:     RHEL 7.6.0 PC (i440FX + PIIX, 1996)


Please help to check this, if no more comments I will move this bug to VERIFIED, thanks.



Best regards
Liu Nana

Comment 11 Dr. David Alan Gilbert 2022-01-24 15:33:38 UTC

Yes, that's right - you see the 'smp 8' has turned into 8 sockets x 1 core.
I think if you try it with the 8.6.0 q35 machine type you'll see probably 1 socket, 8 cores.

Comment 12 liunana 2022-01-25 14:25:21 UTC

(In reply to Dr. David Alan Gilbert from comment #11)
> Yes, that's right - you see the 'smp 8' has turned into 8 sockets x 1 core.
> I think if you try it with the 8.6.0 q35 machine type you'll see probably 1
> socket, 8 cores.

Yes,I can see the difference with 8.6.0 q35 machine type with qemu-kvm-6.2.0-5.module+el8.6.0+14006+80bd780c

Inside guest:
# lscpu

Thread(s) per core:  1
Core(s) per socket:  8
Socket(s):           1
BIOS Model name:     RHEL-8.6.0 PC (Q35 + ICH9, 2009)



Move this bug to verified now, thanks.

Comment 14 errata-xmlrpc 2022-05-10 13:24:19 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 (Moderate: virt:rhel and virt-devel:rhel security, bug fix, and enhancement update), 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/RHSA-2022:1759