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Date: Tue, 7 Feb 2012 10:17:27 +0000
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20120207101727.GC29427@stefanha-thinkpad.localdomain>
References: <20120201030557.2990.74150.sendpatchset@skannery.in.ibm.com>
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Subject: Re: [Qemu-devel] [RFC Patch 5/7]Qemu: raw-posix image file reopen
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To: Supriya Kannery <supriyak@linux.vnet.ibm.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>

On Wed, Feb 01, 2012 at 08:37:12AM +0530, Supriya Kannery wrote:
> +    /* stash state before reopen */
> +    raw_rs->stash_s = g_malloc0(sizeof(BDRVRawState));
> +    memcpy(raw_rs->stash_s, s, sizeof(BDRVRawState));

Copying a struct is fragile, Mike Roth pointed out the potential issue
with aligned_buf.

If raw-posix could open from a given file descriptor as an alternative
to opening a filename, then it would be clean and natural to simply
re-initialize from the dup'd file descriptor in the abort case.  That's
the approach I would try instead of stashing the whole struct.

Stefan