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Date: Mon, 05 Jul 2010 17:31:06 +0200
From: Kevin Wolf <kwolf@redhat.com>
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Subject: [Qemu-devel] Re: [PATCH 03/11] raw-posix: Don't "try harder" for
	BDRV_TYPE_CDROM
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To: Markus Armbruster <armbru@redhat.com>
Cc: hch@lst.de, qemu-devel@nongnu.org, kraxel@redhat.com

Am 30.06.2010 13:55, schrieb Markus Armbruster:
> raw_pread_aligned() retries up to two times if the block device backs
> a virtual CD-ROM.  This makes no sense.  Whether retrying reads can
> correct read errors may depend on what we're reading, not on how the
> result gets used.
> 
> Also clean up gratuitous use of goto.
> 
> This reverts what's left of commit 8c05dbf9.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>

Are you sure that this won't cause a regression? I mean if there is a
patch specifically adding this behaviour, there probably was a problem
that made someone touch the code in the first place.

Arguably checking for the type hint is nonsense, however I think the
case for which this was written is passing through a real CD-ROM to a VM
- in which case the condition would be true anyway.

So instead of removing the code, the fix to achieve what was probably
intended is to check for bs->drv == &bdrv_host_cdrom.

Kevin