Message-ID: <3E356854.1090100@google.com>
Date: Mon, 27 Jan 2003 09:11:48 -0800
From: Ross Biro <rossb@google.com>
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.0.1) Gecko/20020826
MIME-Version: 1.0
To: linux-kernel@vger.kernel.org
Subject: BUG: [2.4.18+] IDE Race Condition
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org


There is at least one more IDE race condition in 2.4.18 and 2.4.21-pre3. 
 Basically the interrupt for the controller being serviced is left on 
while setting up the next command.  I'm not sure how much trouble it can 
cause but it does lead to some interesting stack traces.

The condition
if (masked_irq && hwif->irq != masked_irq)
in ide_do_request should be replaced with
if (!masked_irq || hwif->irq != masked_irq)
in two places.

This doesn't totally eliminate the race conditions, but it does minimize 
them some more.  I can still see a race in 2.4.18.  I'll say more about 
it once I've tracked it down.

    Ross


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