Re: [KVM PATCH v8 1/3] KVM: Fix races in irqfd using new eventfd_kref_get interface

From: Avi Kivity <avi@redhat.com>
To: Gregory Haskins <ghaskins@novell.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	mst@redhat.com, davidel@xmailserver.org
Subject: Re: [KVM PATCH v8 1/3] KVM: Fix races in irqfd using new eventfd_kref_get interface
Date: Thu, 02 Jul 2009 17:16:44 +0300	[thread overview]
Message-ID: <4A4CC14C.1000905@redhat.com> (raw)
In-Reply-To: <20090701160902.3615.39426.stgit@dev.haskins.net>

On 07/01/2009 07:09 PM, Gregory Haskins wrote:
> eventfd currently emits a POLLHUP wakeup on f_ops->release() to generate a
> "release" callback.  This lets eventfd clients know if the eventfd is about
> to go away and is very useful particularly for in-kernel clients.  However,
> until recently it is not possible to use this feature of eventfd in a
> race-free way.
>
> This patch utilizes a new eventfd interface to rectify the problem.  It also
> converts the eventfd POLLHUP generation code to use the locked variant
> of wakeup.
>
> Signed-off-by: Gregory Haskins<ghaskins@novell.com>
> CC: Davide Libenzi<davidel@xmailserver.org>
> ---
>
>   fs/eventfd.c             |    7 --
>   include/linux/kvm_host.h |    5 +
>   virt/kvm/eventfd.c       |  187 ++++++++++++++++++++++++++++++++--------------
>   3 files changed, 134 insertions(+), 65 deletions(-)
>    

Please split the eventfd.c hunk into a separate patch.  When preparing 
the 2.6.32 submission, I'll fold that into the patch into its antipatch 
and they'll disappear.

-- 
error compiling committee.c: too many arguments to function