[SCSI] fix sym scsi boot hang

On Wed, 2005-09-14 at 18:06 +1000, Anton Blanchard wrote:
> And in particular it looks like the scsi_unprep_request in
> scsi_queue_insert is causing it. The following patch fixes the boot
> problems on the vscsi machine:

OK, my fault.  Your fix is almost correct .. I was going to do this
eventually, honest, because there's no need to unprep and reprep a
command that comes in through scsi_queue_insert().

However, I decided to leave it in to exercise the scsi_unprep_request()
path just to make sure it was working.  What's happening, I think, is
that we also use this path for retries.  Since we kill and reget the
command each time, the retries decrement is never seen, so we're
retrying forever.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>