From: Ingo Molnar <mingo@elte.hu>
To: Jan Luebbe <jluebbe@lasnet.de>
Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org
Subject: Re: [PATCH] fix console change race exposed by CFS
Date: Sun, 30 Sep 2007 09:20:56 +0200 [thread overview]
Message-ID: <20070930072056.GA18108@elte.hu> (raw)
In-Reply-To: <1191084471.24185.11.camel@polaris>
* Jan Luebbe <jluebbe@lasnet.de> wrote:
> From: Jan Lübbe <jluebbe@lasnet.de>
>
> The new behaviour of CFS exposes a race which occurs if a switch is
> requested when vt_mode.mode is VT_PROCESS.
>
> The process with vc->vt_pid is signaled before vc->vt_newvt is set. This
> causes the switch to fail when triggered by the monitoing process
> because the target is still -1.
>
> Signed-off-by: Jan Lübbe <jluebbe@lasnet.de>
nifty! I'm wondering what the symptoms of this bug were - how did you
notice it? Also, i'm wondering how you managed to debug this - looks
quite hard to trigger this race, right?
Acked-by: Ingo Molnar <mingo@elte.hu>
Ingo
next prev parent reply other threads:[~2007-09-30 7:21 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-09-29 16:47 [PATCH] fix console change race exposed by CFS Jan Luebbe
2007-09-30 7:20 ` Ingo Molnar [this message]
2007-09-30 8:31 ` Jan Luebbe
2007-09-30 15:53 ` Ingo Molnar
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