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From: Rusty Russell <rusty@rustcorp.com.au>
To: Nick Piggin <npiggin@suse.de>
Subject: Re: Is module refcounting racy?
Date: Mon, 29 Mar 2010 19:42:56 +1030
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On Thu, 18 Mar 2010 09:25:34 pm Nick Piggin wrote:
> Hey,
> 
> I've been looking at weird and wonderful ways to do scalable refcounting,
> for the vfs...
> 
> Sadly, module refcounting doesn't fit my bill. But as far as I could see,
> it is racy.

Other than for advisory purposes, the refcount is only checked against zero
under stop_machine.  For exactly this reason.

Hope that helps,
Rusty.