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Subject: Re: [Qemu-devel] Re: [PATCH] scsi-generic: bugfixes for
	'SCSIRequest' conversion
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
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Date: Thu, 25 Nov 2010 19:46:14 +1100
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To: Hannes Reinecke <hare@suse.de>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, qemu-devel <qemu-devel@nongnu.org>, "Nicholas A. Bellinger" <nab@linux-iscsi.org>, Gerd Hoffmann <kraxel@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>, linux-iscsi-target-dev@googlegroups.com

On Wed, 2010-11-24 at 11:46 +0100, Hannes Reinecke wrote:
> >> - when a read is aborted due to a mark/EOF/EOD/EOM, the len
> reported to
> >> controller can be 0. LSI controller emulation doesn't know how to
> manage
> >> this. A workaround found is to call the completion routine with
> >> SCSI_REASON_DONE just after calling it with SCSI_REASON_DATA with
> len=0.
> > 
> > Are you sure that it's not needed any more?
> > 
> Don't ask me. I didn't do the patch, and my knowledge of lsi HBA
> internals is scanty.
> Nic, can you comment here? 

Well, writing an HBA myself, it took me a while to figure out what I'm
supposed to expect from the layer :-)

So far tho, it appears that I can (at least with scsi-disk) rely on
always been eventually called with SCSI_REASON_DONE so my code (and
maybe the usb-msd code too, I haven't verified) relies on that to
complete requests... Is that incorrect ?

Cheers,
Ben.