From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Hellwig <hch@infradead.org>
Subject: Re: [PATCH 1/3] SCSI: Make cmd_serial_number an atomic
Date: Sun, 3 Apr 2011 09:33:06 -0400
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To: Matthew Wilcox <matthew@wil.cx>
Cc: Christoph Hellwig <hch@infradead.org>, Matthew Wilcox <willy@linux.intel.com>, linux-scsi@vger.kernel.org, "Moore, Eric" <Eric.Moore@lsi.com>

On Sun, Apr 03, 2011 at 07:15:43AM -0600, Matthew Wilcox wrote:
> Hm, yeah, it looks like it's only used for checking whether the command
> we're aborting is the same command we're using to do the aborts.  In
> which case, can't we simply do this?  Eric?

A similar question also applies for the old fusion driver.  There it
even compares the serial number with one taken from the same scsi_cmnd
in the same function.  If we could reuse a scsi_cmnd while in the
->eh_abort handler for fusion it would have to seriously mess up it's
locking and lifetime rules.