linux-kernel - Re: 2.6.24-rc3-mm1

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Wed, 12 Dec 2007 12:08:22 +0200
From:	Boaz Harrosh <bharrosh@...asas.com>
To:	James Bottomley <James.Bottomley@...senPartnership.com>,
	Jens Axboe <jens.axboe@...cle.com>
CC:	Andrew Morton <akpm@...ux-foundation.org>,
	Gabriel C <nix.or.die@...glemail.com>,
	linux-kernel@...r.kernel.org, linux-scsi@...r.kernel.org,
	Hannes Reinecke <hare@...e.de>
Subject: Re: 2.6.24-rc3-mm1

On Tue, Dec 11 2007 at 18:33 +0200, James Bottomley <James.Bottomley@...senPartnership.com> wrote:
> On Mon, 2007-11-26 at 22:15 -0800, Andrew Morton wrote:
>> OK, thanks.  I'll assume that James and Hannes have this in hand (or will
>> have, by mid-week) and I won't do anything here.
> 
> Just to confirm what I think I'm going to be doing:  rebasing the
> scsi-misc tree to remove this commit:
> 
> commit 8655a546c83fc43f0a73416bbd126d02de7ad6c0
> Author: Hannes Reinecke <hare@...e.de>
> Date:   Tue Nov 6 09:23:40 2007 +0100
> 
>     [SCSI] Do not requeue requests if REQ_FAILFAST is set
> 
> And its allied fix ups:
> 
> commit 983289045faa96fba8841d3c51b98bb8623d9504
> Author: James Bottomley <James.Bottomley@...senPartnership.com>
> Date:   Sat Nov 24 19:47:25 2007 +0200
> 
>     [SCSI] fix up REQ_FASTFAIL not to fail when state is QUIESCE
> 
> commit 9dd15a13b332e9f5c8ee752b1ccd9b84cb5bdf17
> Author: James Bottomley <James.Bottomley@...senPartnership.com>
> Date:   Sat Nov 24 19:55:53 2007 +0200
> 
>     [SCSI] fix domain validation to work again
> 
> James
> 

The problems caused by this patch where nagging me at the back of my head
from the begging. Why should we fail on a check of FAIL_FAST in all kind
of weird places like boots, when the only place that should ever set the 
flag should be one of the multi-path drivers. finally it struck me:

It might be a bug in ll_rw_blk at blk_rq_bio_prep() there is this:

static void blk_rq_bio_prep(struct request_queue *q, struct request *rq,
			    struct bio *bio)
{
	/* first two bits are identical in rq->cmd_flags and bio->bi_rw */
	rq->cmd_flags |= (bio->bi_rw & 3);
	...

Now this is no longer true and is a bug.
Second bit of bio->bi_rw defined in bio.h is:
#define BIO_RW_AHEAD	1
but
Second bit of rq->cmd_flags is __REQ_FAILFAST

so maybe we are getting FAILFAST in the wrong places?

(I will look for an old patch I sent a year ago that fixes
this bug)

Boaz
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/