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Date: Tue, 23 Jun 2009 20:26:22 +0200
From: Christoph Hellwig <hch@lst.de>
Subject: Re: [Qemu-devel] [PATCH] block: Clean up after deleting BHs
Message-ID: <20090623182622.GA5804@lst.de>
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To: Avi Kivity <avi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org

On Tue, Jun 23, 2009 at 07:57:01PM +0300, Avi Kivity wrote:
> >I think not having the state of the private acb area cleared over a
> >free/realloc cycle is pretty dangerous.  Wouldn't it be better to always
> >clear that space in qemu_aio_get?
> >   
> 
> Maybe, but that's a bigger change.  Let's start with this (in stable- 
> too) and rework aio later.

It's actually smaller - half the size to be exact :)

Signed-off-by: Christoph Hellwig <hch@lst.de>

Index: qemu/block.c
===================================================================
--- qemu.orig/block.c	2009-06-23 20:16:48.283930485 +0200
+++ qemu/block.c	2009-06-23 20:16:57.158834441 +0200
@@ -1515,6 +1515,7 @@ void *qemu_aio_get(AIOPool *pool, BlockD
     acb->bs = bs;
     acb->cb = cb;
     acb->opaque = opaque;
+    memset(acb + 1, 0, pool->aiocb_size - sizeof(BlockDriverAIOCB));
     return acb;
 }