From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa@zytor.com>
Subject: Re: "simultaneous" mounts causing weird behavior
Date: Tue, 04 Nov 2003 13:03:30 -0800
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To: Matthew Mitchell <matthew@geodev.com>
Cc: autofs@linux.kernel.org

Matthew Mitchell wrote:
> 
> Yes, I know that mount can do that now.  But automount is spawning the
> second mount before the first one completes, no?  Still seems like there
> should be some sort of mutual exclusion around the lookup_mount call.  I
> realize our workload is kind of funny in that the processes effectively
> _try_ to synchronize their automount request.  
> 

autofs 3 relied on the mutural exclusion inherent in mount(2).  When
this was changed, it introduced a race condition in autofs 3.  I have
asked to add a mount flag to override this new behaviour; I don't know
if one was ever introduced or added to mount(8).

> Has any of this changed in the 4.0-pre autofs?  I haven't read through
> its source yet.

autofs 4 uses a different mutural exclusion strategy, so I would *think*
it would not be affected.

	-hpa