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From: Dave Jones <davej@redhat.com>
To: Linux Kernel <linux-kernel@vger.kernel.org>
Subject: soft lockup detector & virtualisation
Date: Thu, 16 Feb 2012 18:15:34 -0500	[thread overview]
Message-ID: <20120216231533.GA7392@redhat.com> (raw)

Lately I've noticed quite a few soft lockup bugs being reported.
In many of them, they're coming from inside virtual guests.

Is the softlockup detector fundamentally broken in this situation ?

If the host doesn't schedule the guest for whatever reason,
or the user suspends the VM and resumes it later ?

Here's the most recent example:
https://bugzilla.redhat.com/attachment.cgi?id=563767

In many of these, the code where it's "stuck" isn't anything
special, which is why I think the guest just hasn't had a
timeslice in 185 seconds.

Is there some way we can perhaps detect we're running virtualised,
and disable the detector automatically ?

thoughts ?

	Dave


             reply	other threads:[~2012-02-16 23:15 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-16 23:15 Dave Jones [this message]
2012-02-17  1:39 ` soft lockup detector & virtualisation john stultz
2012-02-17  1:57   ` Eric B Munson

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