Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261546AbVBNTzV (ORCPT ); Mon, 14 Feb 2005 14:55:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261549AbVBNTzU (ORCPT ); Mon, 14 Feb 2005 14:55:20 -0500 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:43473 "EHLO parcelfarce.linux.theplanet.co.uk") by vger.kernel.org with ESMTP id S261546AbVBNTzL (ORCPT ); Mon, 14 Feb 2005 14:55:11 -0500 Message-ID: <42110210.6030900@pobox.com> Date: Mon, 14 Feb 2005 14:54:56 -0500 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.3) Gecko/20040922 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Takashi Iwai CC: Greg KH , Linux Kernel , Andrew Morton , Alan Cox Subject: Re: avoiding pci_disable_device()... References: <4210021F.7060401@pobox.com> <20050214190619.GA9241@kroah.com> <20050214193413.GA10231@kroah.com> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1834 Lines: 53 Takashi Iwai wrote: > At Mon, 14 Feb 2005 11:34:13 -0800, > Greg KH wrote: > >>On Mon, Feb 14, 2005 at 08:24:29PM +0100, Takashi Iwai wrote: >> >>>At Mon, 14 Feb 2005 11:06:19 -0800, >>>Greg KH wrote: >>> >>>>>As a result, I have committed the attached patch to libata-2.6. In many >>>>>cases, it is a "semantic fix", addressing the case >>>>> >>>>> * pci_request_regions() indicates hardware is in use >>>>> * we rudely disable the in-use hardware >>>>> >>>>>that would not occur in practice. >>>>> >>>>>But better safe than sorry. Code cuts cut-n-pasted all over the place. >>>>> >>>>>I'm hoping one or two things will happen now: >>>>>* janitors fix up the other PCI drivers along these lines >>>>>* improve the PCI API so that pci_request_regions() is axiomatic >>>> >>>>Do you have any suggestions for how to do this? >>> >>>How about to add an exclusiveness check in pci_enable_device()? >>>Most drivers suppose that the given pci resources are exclusively >>>available. >> >>You mean only allow pci_enable_device() to work for the first caller of >>it? I don't see how that would help this issue out. > > > Well, for example, add a new pointer to indicate the driver accessing > exclusively. And pci_enable_device() (maybe a new variant would be > better for compatibility) checks whether this is free. > > The second caller wouldn't reach even to pci_request_regions() because > of this check. So, no side-effect of pci_disable_device() in the > error path. This doesn't work with a driver that is properly using request_resource(), but not using the PCI API. Jeff - 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/