From mboxrd@z Thu Jan  1 00:00:00 1970
From: Avi Kivity <avi@redhat.com>
Subject: Re: [PATCHv2 1/3] eventfd: allow atomic read and waitqueue remove
Date: Thu, 21 Jan 2010 19:56:02 +0200
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Cc: Davide Libenzi <davidel@xmailserver.org>, mtosatti@redhat.com,
	kvm@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
To: "Michael S. Tsirkin" <mst@redhat.com>
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On 01/21/2010 07:45 PM, Michael S. Tsirkin wrote:
>
>> But you're in process context.  An eventfd never blocks.
>>      
> Yes it blocks if counter is 0. And we don't know
> it's not 0 unless we read :) catch-22.
>    

Ah yes, I forgot.

-- 
Do not meddle in the internals of kernels, for they are subtle and quick to panic.