From mboxrd@z Thu Jan  1 00:00:00 1970
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Subject: Re: usercopy whitelist woe in scsi_sense_cache
From: James Bottomley <jejb@linux.vnet.ibm.com>
To: Kees Cook <keescook@chromium.org>,
        Oleksandr Natalenko
	 <oleksandr@natalenko.name>,
        Jens Axboe <axboe@kernel.dk>,
        Bart Van Assche
	 <bart.vanassche@wdc.com>,
        Paolo Valente <paolo.valente@linaro.org>
Cc: David Windsor <dave@nullcore.net>,
        "Martin K. Petersen"
 <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, LKML
 <linux-kernel@vger.kernel.org>,
        Christoph Hellwig <hch@lst.de>, Hannes
 Reinecke <hare@suse.com>,
        Johannes Thumshirn <jthumshirn@suse.de>, linux-block@vger.kernel.org
Date: Tue, 17 Apr 2018 11:02:08 +0100
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On Mon, 2018-04-16 at 20:12 -0700, Kees Cook wrote:
> I still haven't figured this out, though... any have a moment to look
> at this?

Just to let you know you're not alone ... but I can't make any sense of
this either.  The bfdq is the elevator_data, which is initialised when
the scheduler is attached, so it shouldn't change.  Is it possible to
set a data break point on elevator_data after it's initialised and see
if it got changed by something?

James