Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764836AbXEWAie (ORCPT ); Tue, 22 May 2007 20:38:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761715AbXEWAiT (ORCPT ); Tue, 22 May 2007 20:38:19 -0400 Received: from outbound-mail-65.bluehost.com ([69.89.21.25]:56982 "HELO outbound-mail-65.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1761546AbXEWAiS (ORCPT ); Tue, 22 May 2007 20:38:18 -0400 From: Jesse Barnes To: Robert Hancock Subject: Re: [RFC PATCH] PCI MMCONFIG: add validation against ACPI motherboard resources Date: Tue, 22 May 2007 17:38:09 -0700 User-Agent: KMail/1.9.6 Cc: Olivier Galibert , linux-kernel , Andi Kleen , Chuck Ebbert , Len Brown References: <4635510D.4060103@shaw.ca> <200705211322.18937.jbarnes@virtuousgeek.org> <46538B67.3080007@shaw.ca> In-Reply-To: <46538B67.3080007@shaw.ca> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200705221738.09571.jbarnes@virtuousgeek.org> X-Identified-User: {642:box128.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 76.102.120.196 authed with jbarnes@virtuousgeek.org} Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1574 Lines: 31 On Tuesday, May 22, 2007, Robert Hancock wrote: > Eww. I don't see where we disable the decode at all while we probe the > BARs on the device. That seems like a bad thing, especially with the way > we probe 64-bit BARs (do the low 32 bits first and then the high 32 > bits). This means the base address effectively gets set to 0xfffffff0 > momentarily, which might cause some issues. I'm a bit shocked that things work as well as they do without the disabling... > I'd try adding some code inside pci_setup_device (drivers/pci/probe.c) > to disable PCI_COMMAND_IO and PCI_COMMAND_MEMORY on the device when > probing devices with the standard header type and then restoring the > previous command bits afterwards, and see what effect that has. It'll be > interesting if it does, since obviously it seems to work as it is with > non-MMCONFIG access methods. Maybe the base address being set like that > interferes with MMCONFIG access itself somehow? I tried that, and it seems to get past probing the graphics device at least, but it hangs a bit later. It could be that the enable/disable I added wasn't correct though, I didn't check to see which one I should disable in the command word, which may be a problem (just disabled them both every probe). I'll try again with more precise enable/disable semantics. Jesse - 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/