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Date: Sun, 29 Mar 2009 09:31:40 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] [PATCH] check for bs->drv in bdrv_flush
Message-ID: <20090329073140.GA11041@lst.de>
References: <20090328183916.GA25875@lst.de> <49CECFB3.8010407@us.ibm.com>
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To: qemu-devel@nongnu.org

On Sat, Mar 28, 2009 at 08:32:35PM -0500, Anthony Liguori wrote:
> Christoph Hellwig wrote:
> >All the bdrv_ helpers should check for bs->drv being zero as that means
> >there is no backend image open.  bdrv_flush fails to perform that check
> >and can thus cause NULL pointer dereferences.
> >
> >Found using qemu-io.
> >  
> 
> Applied.  Thanks.
> 
> FWIW, I plan to include qemu-io once you rebase the series to use 
> IOVectors instead of struct iovec.  It looks like a useful tool!

The repost already uses QEMUIOVectors, I'll resend it with a
formal description.