From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [patch 1/3] Make rt_down_read_trylock() behave like
 down_read_trylock()
Date: Thu, 9 Apr 2009 15:47:44 +0200 (CEST)
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Cc: rt-users <linux-rt-users@vger.kernel.org>, kvm@vger.kernel.org
To: Jan Blunck <jblunck@suse.de>
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On Wed, 8 Apr 2009, Jan Blunck wrote:

> This patch removes the stupid "Read locks within the self-held write lock
> succeed" behaviour. This is breaking in mm_take_all_locks() since it is quite
> common to ensure that a lock is taken with BUG_ON(down_read_trylock(&mm->mmap_sem)).

Good catch. There are some more oddballs in that file, which we missed
when we moved from 26 to 29 - we dropped the rwlocks stuff and that
cleaned up that area.

Thanks,

	tglx