Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261994AbVEKOmG (ORCPT ); Wed, 11 May 2005 10:42:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261974AbVEKOjC (ORCPT ); Wed, 11 May 2005 10:39:02 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:20096 "HELO iolanthe.rowland.org") by vger.kernel.org with SMTP id S261980AbVEKOiW (ORCPT ); Wed, 11 May 2005 10:38:22 -0400 Date: Wed, 11 May 2005 10:38:16 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Vivek Goyal cc: Alexander Nyberg , Greg KH , Amit Gud , , , , , , USB development list , Maneesh Soni Subject: Re: [PATCH] PCI: Add pci shutdown ability In-Reply-To: <20050511053327.GA28791@in.ibm.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1424 Lines: 31 On Wed, 11 May 2005, Vivek Goyal wrote: > > I looked into the possibility of having the PCI core disable interrupt > > generation and DMA on each new device as it is discovered. Unfortunately > > there is no dependable, universal way to do this for IRQs. (A notable gap > > in the original PCI specification, IMHO.) > > PCI specification 2.3 onwards, command register bit 10 can be used for > disabling the interrupts from respective device. And the very reason for > introducing this bit seems to be to not allow the device issue interrupts > until a suitable driver for the device has been loaded. Have a look at > following message. > > http://www.pcisig.com/reflector/msg05302.html > > Probably this feature can be used to disable the interrupts from the devices > and enable these back when respective driver is loaded. This will resolve > the problem of drivers not getting initialized in second kernel due to shared > interrupts in kdump and reliability of capturing dump can be increased. That's good, and it's certainly a step in the right direction. It won't help with any pre-PCI-2.3 devices out there but it might be worth trying to implement. Alan Stern - 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/