From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH/RFC] PCI prepare/activate instead of enable to avoid IRQ storm and rogue DMA access Date: Wed, 14 Mar 2007 18:34:11 -0400 Message-ID: <45F87863.9040408@garzik.org> References: <20070314152302.GB15600@htj.dyndns.org> <20070314215605.GA7194@flint.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:44873 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1422704AbXCNWeY (ORCPT ); Wed, 14 Mar 2007 18:34:24 -0400 In-Reply-To: <20070314215605.GA7194@flint.arm.linux.org.uk> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: rmk+lkml@arm.linux.org.uk Cc: Tejun Heo , gregkh@suse.de, linux-kernel@vger.kernel.org, linux-pci@atrey.karlin.mff.cuni.cz, michal.k.k.piotrowski@gmail.com, linux-ide@vger.kernel.org, tglx@linutronix.de, shemminger@linux-foundation.org, mlord@pobox.com, linux-pm@lists.osdl.org Russell King wrote: > pci_enable_device() doesn't deal with this; in most PCI setups I've > seen, there is no control at PCI level over whether a device generates > an interrupt on the bus. Certainly the memory and io command enables PCI grew an interrupt enable while you weren't looking: PCI_COMMAND_INTX_DISABLE No idea about ARM, but almost all PCI devices made in the past few years support that bit. Unless you are using a PCI Express device (maybe PCI-X too?), though, you cannot count on the bit's presence. It was added in PCI 2.3 I think. Older PCI devices certainly do not have this standardized bit. Jeff