From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764977AbYD2QOM (ORCPT ); Tue, 29 Apr 2008 12:14:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751946AbYD2QN5 (ORCPT ); Tue, 29 Apr 2008 12:13:57 -0400 Received: from outbound-mail-110.bluehost.com ([69.89.22.10]:36330 "HELO outbound-mail-110.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754656AbYD2QN4 (ORCPT ); Tue, 29 Apr 2008 12:13:56 -0400 From: Jesse Barnes To: linux-pci@atrey.karlin.mff.cuni.cz Subject: Re: [PATCH 1/2] pci/irq: restore mask_bits in msi shutdown -v3 Date: Tue, 29 Apr 2008 09:13:17 -0700 User-Agent: KMail/1.9.9 Cc: "Yinghai Lu" , "Andrew Morton" , "Ingo Molnar" , "David Miller" , "Eric W. Biederman" , tglx@linutronix.de, "Greg KH" , "Jeff Garzik" , "linux-kernel@vger.kernel.org" , "James Bottomley" , "Sathya Prakash" References: <200804222148.17530.yhlu.kernel@gmail.com> <200804251448.21966.jbarnes@virtuousgeek.org> <86802c440804251508w3607dc44yccc720899d94364b@mail.gmail.com> In-Reply-To: <86802c440804251508w3607dc44yccc720899d94364b@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200804290913.17662.jbarnes@virtuousgeek.org> X-Identified-User: {642:box128.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 75.111.27.49 authed with jbarnes@virtuousgeek.org} Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday, April 25, 2008 3:08 pm Yinghai Lu wrote: > On Fri, Apr 25, 2008 at 2:48 PM, Jesse Barnes wrote: > > On Wednesday, April 23, 2008 2:56 pm Yinghai Lu wrote: > > > Yinghai found after using 2.6.25-rc3 later to kexec RHEL 5.1, > > > NIC can not be used. > > > > > > bisected to > > > > Hi Yinghai, I've been thinking about these patches a bit... They seem > > like an important bug fix (making sure kexec'd kernels work), but I'm a > > bit worried that the kexec'd kernel can't handle potentially broken > > MSI/INTx setups. Shouldn't the kexec'd kernel be a bit more robust? I > > guess in this case you're kexec'ing an old kernel, so there's not much we > > can do, but it still makes me a little uneasy. > > Yes, it is important, and should be in 2.6.25 stable too. > > the maskbits always 0x00 (enabled) from BIOS post..., so we should restore > that. > > > I guess for this particular set it doesn't matter much, since we should > > be restoring things in pci_msi*_shutdown and pci_shutdown_device either > > way. Can you clean up the changelog a bit and maybe make it more concise? > > E.g. we probably don't need the whole commit message for the bisect, and > > we want to be clearer about what the failure mode is w/o the changes... > > without it, the second kernel can not use the devices, if second > kernel could use MSI but doesn't touch mask_bit. > > --- > [PATCH 1/2] pci/irq: restore mask_bits in msi shutdown -v3 > > Yinghai found after using 2.6.25-rc3 later to kexec RHEL 5.1, > NIC can not be used. > > bisected to > > | commit 89d694b9dbe769ca1004e01db0ca43964806a611 > | Author: Thomas Gleixner > | Date: Mon Feb 18 18:25:17 2008 +0100 > | > | genirq: do not leave interupts enabled on free_irq > | > | The default_disable() function was changed in commit: > | > | 76d2160147f43f982dfe881404cfde9fd0a9da21 > | genirq: do not mask interrupts by default > > for MSI, default_shutdown will call mask_bit for msi device. so all mask > bits will left disabled after free_irq. then if kexec next kernel that > only can use msi_enable bit. all device's MSI can not be used. > > So lets to restore the mask bit to it's pci reset defined value (enabled) > when we disable the kernels use of msi. > > extend msi_set_mask_bit to msi_set_mask_bits to take mask, so we can fully > restore that to 0x00 instead of 0xfe. > > Signed-off-by: Yinghai Lu Applied both (fixed up the changelog a little though), thanks. Jesse