From mboxrd@z Thu Jan  1 00:00:00 1970
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Date: Tue, 02 Sep 2008 15:36:02 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-core] [PATCH] POSIX: Fix race when setting claimed bit
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To: Jan Kiszka <jan.kiszka@domain.hid>
Cc: xenomai-core <xenomai@xenomai.org>

Jan Kiszka wrote:
> Patch 2 of my fast lock series actually also contained an attempt to fix
> a race I spotted in the code that atomically sets the claimed bit. I
> forgot about this fact and even, worse, I only replace the original race
> with another one.
> 
> So here comes a new attempt to fix the issue that the lock owner and/or
> the claimed bit can change between trylock and the cmpxchg under nklock.
> Please have a look and cross-check the logic.
> 
> The patch applies on top of vanilla SVN, so my series has to be rebased
> and the fix has to be ported to native as well - where we just found it
> in the field.

Could you explain the race ?

-- 
                                                 Gilles.