From: Philipp Hahn <hahn@univention.de>
To: xen-devel@lists.xen.org
Cc: Thomas Gleixner <tglx@linutronix.de>,
David Vrabel <david.vrabel@citrix.com>
Subject: Re: [BUG 2.6.32.y] Broken PV migration between hosts with different uptime, non-monotonic time?
Date: Fri, 4 May 2012 15:10:53 +0200 [thread overview]
Message-ID: <201205041510.56986.hahn@univention.de> (raw)
In-Reply-To: <4FA3B1C7.4060201@citrix.com>
[-- Attachment #1.1: Type: text/plain, Size: 1228 bytes --]
Hello David,
On Friday 04 May 2012 12:39:03 David Vrabel wrote:
> On 04/05/12 09:54, Philipp Hahn wrote:
> > I encountered the following bug when migrating a Linux-2.6.32.54 PV
> > domain on Xen-3.4.3 between different hosts, whose uptime differs by
> > several minutes
...
> Xen 3.4 doesn't ensure that the TSC is stable across migrates (Xen 4.0
> does). If the host CPU has the CONSTANT_TSC bit in the Advanced Power
> Management CPUID leaf it will pass this through to the guest which makes
> the guest think the TSC is stable.
>
> Can you try this libxc patch?
>
> 8<------------------------
> libxc: clear CONSTANT_TSC bit in Advanced Power Management CPUID leaf
Excellent, that fixes the problem for me and makes perfect sense for me, since
AFAIK 2.6.37 also received a big TSC patch which is not part of 2.6.32.y
backport.
Thank your for your help.
Sincerely
Philipp Hahn
--
Philipp Hahn Open Source Software Engineer hahn@univention.de
Univention GmbH be open. fon: +49 421 22 232- 0
Mary-Somerville-Str.1 D-28359 Bremen fax: +49 421 22 232-99
http://www.univention.de/
[-- Attachment #1.2: This is a digitally signed message part. --]
[-- Type: application/pgp-signature, Size: 197 bytes --]
[-- Attachment #2: Type: text/plain, Size: 126 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
http://lists.xen.org/xen-devel
next prev parent reply other threads:[~2012-05-04 13:10 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-04 8:54 [BUG 2.6.32.y] Broken PV migration between hosts with different uptime, non-monotonic time? Philipp Hahn
2012-05-04 10:39 ` David Vrabel
2012-05-04 13:10 ` Philipp Hahn [this message]
2012-05-04 13:20 ` David Vrabel
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=201205041510.56986.hahn@univention.de \
--to=hahn@univention.de \
--cc=david.vrabel@citrix.com \
--cc=tglx@linutronix.de \
--cc=xen-devel@lists.xen.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).