From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH] Fix aic7xxx del_timer_sync() deadlock Date: Sun, 29 Feb 2004 15:28:54 -0500 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <40424B86.3000703@pobox.com> References: <4041292C.3090700@pobox.com> <20040229091350.GC3149@suse.de> <137982704.1078081053@aslan.btc.adaptec.com> <404236C1.5000001@pobox.com> <156412704.1078082931@aslan.btc.adaptec.com> <40423F7B.4020102@pobox.com> <162922704.1078083749@aslan.btc.adaptec.com> <4042410C.7070701@pobox.com> <20040229200636.GI31904@suse.de> <404249AA.4050808@pobox.com> <20040229202742.GJ31904@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:10706 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id S262131AbUB2U3G (ORCPT ); Sun, 29 Feb 2004 15:29:06 -0500 In-Reply-To: <20040229202742.GJ31904@suse.de> List-Id: linux-scsi@vger.kernel.org To: Jens Axboe Cc: "Justin T. Gibbs" , James Bottomley , SCSI Mailing List , Andrew Morton Jens Axboe wrote: > On Sun, Feb 29 2004, Jeff Garzik wrote: > >>Jens Axboe wrote: >> >>>Don't forget that this isn't the only condition. What about pci dma >>>mapping failures? >> >> >>hehe, granted there might be other conditions, but for PCI DMA mapping >>specifically, it is (unfortunately) currently defined to not fail. > > > Which is bogus and must be changed anyways... Besides, that was just one > example. There could be other resource shortages that can happen which > prevent queueing. Agreed. >>That wants changing for ppc64 and x86-64 iommu, which are a -lot- more >>likely to fail an iommu transaction than parisc or sparc64... but that's >>the way it is for now. Way too many drivers assume PCI DMA mapping >>always succeeds. > > > I just don't like _at all_ that it's assumed it cannot fail, when in > fact it _can_ fail. Likeliness just means it's less of a problem for > those archs, it's still an eye sore. I agree with you completely... but the current PCI DMA API is reality. We just need to change reality. :) Jeff