From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH 1/3] macvtap: rework object lifetime rules
Date: Thu, 18 Feb 2010 14:11:26 -0800 (PST)
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From: Arnd Bergmann <arnd@arndb.de>
Date: Thu, 18 Feb 2010 16:45:36 +0100

> This reworks the change done by the previous patch
> in a more complete way.
> 
> The original macvtap code has a number of problems
> resulting from the use of RCU for protecting the
> access to struct macvtap_queue from open files.
> 
> This includes
> - need for GFP_ATOMIC allocations for skbs
> - potential deadlocks when copy_*_user sleeps
> - inability to work with vhost-net
> 
> Changing the lifetime of macvtap_queue to always
> depend on the open file solves all these. The
> RCU reference simply moves one step down to
> the reference on the macvlan_dev, which we
> only need for nonblocking operations.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Applied.