From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jens Axboe Subject: Re: Fw: PROBLEM: Linux V. 2.6.3 panics with "Buffers at physical address >16Mb used for aha1542" at boot time Date: Mon, 23 Feb 2004 20:04:22 +0100 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <20040223190422.GL32010@suse.de> References: <20040218171212.0eb6618a.akpm@osdl.org> <1077243517.2164.61.camel@mulgrave> <1077265837.1297.9.camel@felicia> <20040220083808.GA11822@suse.de> <1077300620.1937.11.camel@mulgrave> <20040223164811.GK32010@suse.de> <1077557656.1759.58.camel@mulgrave> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from ns.virtualhost.dk ([195.184.98.160]:6058 "EHLO virtualhost.dk") by vger.kernel.org with ESMTP id S262002AbUBWTEh (ORCPT ); Mon, 23 Feb 2004 14:04:37 -0500 Content-Disposition: inline In-Reply-To: <1077557656.1759.58.camel@mulgrave> List-Id: linux-scsi@vger.kernel.org To: James Bottomley Cc: "Dr. Ernst Molitor" , Andrew Morton , SCSI Mailing List On Mon, Feb 23 2004, James Bottomley wrote: > On Mon, 2004-02-23 at 10:48, Jens Axboe wrote: > > Something half-assed like this should work as an immediate fix... > > But I don't see how this bounces the buffer? Without a bio, this simply > passes req->data (which is cgc->buffer) into cmd->request_buffer in > scsi_init_io(); but the problem was that this buffer is outside the > dma_mask. Duh you are right, I completely forgot about that. Well that really settles the fact that it must be bio backed, and that use_sg should just die in the same iteration. It was a step in the wrong direction regardless, I'd love to kill ->data eventually. Anyways, I have another way to solve this without shaking scsi_wait_req() up too much. The way I see it, you cannot implement what you want there, you simply don't have access to everything you need to make it possible. The best way is to add a few helpers to map to a (bio backed) request and have sr/sd/st call these to set things up. I'll give that a go. -- Jens Axboe