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Date: Sun, 16 May 2010 15:29:17 +0200
From: Christoph Hellwig <hch@lst.de>
Message-ID: <20100516132917.GA27075@lst.de>
References: <1273930252-12673-1-git-send-email-nab@linux-iscsi.org>
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Subject: [Qemu-devel] Re: [PATCH 1/2] [block]: Fix scsi-generic breakage in
	find_image_format()
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To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: Kevin Wolf <kwolf@redhat.com>, kvm-devel <kvm@vger.kernel.org>, qemu-devel <qemu-devel@nongnu.org>, Hannes Reinecke <hare@suse.de>, Christoph Hellwig <hch@lst.de>, Gerd Hoffmann <kraxel@redhat.com>

On Sat, May 15, 2010 at 06:30:52AM -0700, Nicholas A. Bellinger wrote:
> From: Nicholas Bellinger <nab@linux-iscsi.org>
> 
> This patch adds a special BlockDriverState->sg check in block.c:find_image_format()
> after bdrv_file_open() -> block/raw-posix.c:hdev_open() has been called to determine
> if we are dealing with a Linux host scsi-generic device or not.
> 
> The patch then returns the BlockDriver * from find_protocol(), skipping the subsequent
> bdrv_read() and rest of find_image_format().

That's not quite correct as we don't want to expose formats directly.
Returning

	bdrv_find_format("raw");

should fix it for now, although I really hate having these special
cases in block.c.