[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

[libvirt] possible bug regarding cpu flag 'pclmulqdq' in cpu_map.xml



-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Hi,

laine on IRC was so kind to redirect me to this list, so
I didn't file a BZ at:
https://bugzilla.redhat.com/enter_bug.cgi?product=Virtualization%20Tools
&component=libvirt
yet.

Please keep me CC'ed as I'm not subscribed to the list.

So here is my bug report:

Description of problem:
I believe the flag "pclmulqdq" is wrongly spelled in cpu_map.xml
leading to wrong cpu
being detected:

Version-Release number of selected component (if applicable):
current master:
https://libvirt.org/git/?p=libvirt.git;a=blob;f=src/cpu/cpu_map.xml;h=21
10c0b9b2a2a70f0334b2ff63416bd1b704b669;hb=HEAD

How reproducible:
always

Steps to Reproduce:
1.install e.g. ovirt, or some other libvirt consumer on a system with
a cpu like intel xeon E3-1230
2. it will get reported as nehalem
3.

Actual results:
cpu gets reported as "nehalem"

Expected results:
cpu gets reported as "sandy bridge"

Additional info:
I found no real info on this flag:
grep --color pclmuldq /usr/share/libvirt/cpu_map.xml
    <feature name='pclmuldq'>
      <feature name='pclmuldq'/>
      <feature name='pclmuldq'/>

wikipedia (not always right, I know) and Intel
just seem to know the flag
'pclmulqdq'

See:
https://en.wikipedia.org/wiki/CLMUL_instruction_set
https://en.wikipedia.org/wiki/CPUID#EAX.3D1:_Processor_Info_and_Feature_
Bits
https://software.intel.com/file/36945

But the Intel documentation is vast and I might have
missed information on their website.

So please check if this is the correct cpu flag indeed.

Thanks!

PS: If this is a real bug, it goes way back
into el6 released versions of libvirt, and
I would like to see a backport, if possible!

Here is the BZ which introduced the flag:
https://bugzilla.redhat.com/show_bug.cgi?id=761005
I guess this got wrongly typed, when you look
at this comment, which has the correct notation:
https://bugzilla.redhat.com/show_bug.cgi?id=761005#c16

- -- 
Mit freundlichen Grüßen / Regards

Sven Kieske

Systemadministrator
Mittwald CM Service GmbH & Co. KG
Königsberger Straße 6
32339 Espelkamp
T: +49-5772-293-100
F: +49-5772-293-333
https://www.mittwald.de
Geschäftsführer: Robert Meyer
St.Nr.: 331/5721/1033, USt-IdNr.: DE814773217, HRA 6640, AG Bad Oeynhaus
en
Komplementärin: Robert Meyer Verwaltungs GmbH, HRB 13260, AG Bad
Oeynhausen
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
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=ergB
-----END PGP SIGNATURE-----


[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]