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From: "John David Anglin" <dave@hiauly1.hia.nrc.ca>
To: carlos@systemhalted.org (Carlos O'Donell)
Cc: dave.anglin@nrc-cnrc.gc.ca, mroos@linux.ee,
	linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: 2.6.38-rc3 regression on parisc: segfaults
Date: Fri, 4 Feb 2011 11:17:06 -0500 (EST)	[thread overview]
Message-ID: <20110204161706.B544B4DF4@hiauly1.hia.nrc.ca> (raw)
In-Reply-To: <AANLkTim9oXFf7ksuj9o-g2J4aL4xi-JPH3PsayMayxMt@mail.gmail.com> from "Carlos O'Donell" at Feb 4, 2011 10:20:05 am

> > This is possibly the infamous COW bug.
> 
> The COW bug that is triggered by a COW from an LWS-CAS? The solution
> to which is to use locks around the LWS-CAS even on UP? I'd forgotten
> about this issue actually, I should push that patch out to James.

I was actually thinking of the fork/clone race for which there are various
testcases on the wiki.  The aptitude segv is with a SMP kernel, so I don't
think this is the UP LWS_CAS issue.  However, I agree you should push
the change.

Dave
-- 
J. David Anglin                                  dave.anglin@nrc-cnrc.gc.ca
National Research Council of Canada              (613) 990-0752 (FAX: 952-6602)

      reply	other threads:[~2011-02-04 16:17 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-02-01 22:00 Meelis Roos
2011-02-01 22:12 ` James Bottomley
2011-02-03 22:36   ` Meelis Roos
2011-02-01 22:16 ` Carlos O'Donell
2011-02-03  2:24 ` John David Anglin
2011-02-03  7:03   ` Meelis Roos
2011-02-04 10:11   ` Meelis Roos
2011-02-04 15:07     ` John David Anglin
2011-02-04 15:20       ` Carlos O'Donell
2011-02-04 16:17         ` John David Anglin [this message]

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