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From: "Alan D. Brunelle" <adbrunelle@gmail.com>
To: Hannes Reinecke <hare@suse.de>
Cc: Jens Axboe <jens.axboe@oracle.com>,
	scameron@beardog.cca.cpqcorp.net, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] cciss: Ignore stale commands after reboot
Date: Mon, 06 Jul 2009 16:33:44 -0400	[thread overview]
Message-ID: <4A525FA8.80509@gmail.com> (raw)
In-Reply-To: <20090702082313.F3754D340B@pentland.suse.de>

Hannes Reinecke wrote:
> When doing an unexpected shutdown like kexec the cciss
> firmware might still have some commands in flight, which
> it is trying to complete.
> The driver is doing it's best on resetting the HBA,
> but sadly there's a firmware issue causing the firmware
> _not_ to abort or drop old commands.
> So the firmware will send us commands which we haven't
> accounted for, causing the driver to panic.
> 
> With this patch we're just ignoring these commands as
> there is nothing we could be doing with them anyway.
> 
> Signed-off-by: Hannes Reinecke <hare@suse.de>

Pardon my ignorance here, but don't you have a bigger problem: if the 
reset is not dropping or aborting old commands, doesn't this also mean 
that these old commands can still be _executing_? In which case any 
(old) reads being executed could be scribbling over memory? (Memory that 
may be being used for other purposes?)

Alan D. Brunelle


  parent reply	other threads:[~2009-07-06 20:33 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-07-02  8:23 [PATCH] cciss: Ignore stale commands after reboot Hannes Reinecke
2009-07-02  8:28 ` Jens Axboe
2009-07-02  8:44   ` Hannes Reinecke
2009-07-02  9:18     ` Jens Axboe
2009-07-02  9:36       ` Hannes Reinecke
2009-07-02 10:26         ` Jens Axboe
2009-07-02 10:28           ` Hannes Reinecke
2009-07-06 20:33 ` Alan D. Brunelle [this message]
2009-07-07  7:34   ` Hannes Reinecke
  -- strict thread matches above, loose matches on Subject: below --
2009-07-02  9:36 Hannes Reinecke
2009-07-02 19:00 ` Jens Axboe

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