Re: [PATCH] cciss: Ignore stale commands after reboot

From: Alan D. Brunelle
Date: Mon Jul 06 2009 - 16:34:01 EST


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@xxxxxxx>

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

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