From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mark Lord Subject: Re: [BUG] ide dma_timer_expiry, then hard lockup Date: Tue, 19 Jun 2007 11:38:41 -0400 Message-ID: <4677F881.6060200@rtr.ca> References: <20070618175713.GD5836@austin.ibm.com> <20070618212704.394912b8@the-village.bc.nu> <20070618204601.GF5836@austin.ibm.com> <20070618220441.3a3af8ca@the-village.bc.nu> <4677E3BC.3040307@ru.mvista.com> <20070619151919.79c79af1@the-village.bc.nu> <4677E726.1080602@ru.mvista.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from rtr.ca ([64.26.128.89]:4608 "EHLO mail.rtr.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755087AbXFSPin (ORCPT ); Tue, 19 Jun 2007 11:38:43 -0400 In-Reply-To: <4677E726.1080602@ru.mvista.com> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Sergei Shtylyov Cc: Alan Cox , Linas Vepstas , linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org Sergei Shtylyov wrote: > Alan Cox wrote: > >>>>> I can prepare a patch, but only with a lot of guidance. I can test >>>>> & debug, I'm highly motivated just right now ... > >>>> If you've got a nice repeatable problem please try using the libata >>>> driver. That handles the error paths differently and doesn't try a FIFO >>>> drain which might matter in this case I guess. > >>> FIFO drain for DMA commands? > >> Welcome to the old IDE layer which I am so glad I left behind 8) > >> ide_ata_error will try and do a PIO flush regardless of the command type >> if DRQ_STAT is asserted. See ide_dma_intr -> ide_error -> ... > > Indeed... but the thing is we don't know what's asserted in this case > -- remember, it's reading the status register that locks everything up... Exactly. And IORDY shouldn't really apply there, unless some nitwit standards person wrote it into a spec.. -ml