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Date: Tue, 14 Feb 2012 19:06:36 +0530
From: Supriya Kannery <supriyak@linux.vnet.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: Stefan Hajnoczi <stefanha@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Christoph Hellwig <hch@lst.de>, qemu-devel@nongnu.org, Luiz Capitulino <lcapitulino@redhat.com>

On 02/07/2012 03:47 PM, Stefan Hajnoczi wrote:
> 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
>

fine, will get V1 with stashing of only required fields wherever
possible instead of stashing the full struct.