From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Rafael J. Wysocki" Subject: Re: [linux-pm] [PATCH] 3c59x: Get rid of "Trying to free already-free IRQ" Date: Fri, 25 Sep 2009 14:32:30 +0200 Message-ID: <200909251432.30738.rjw@sisk.pl> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Cc: linux-pm@lists.linux-foundation.org, Anton Vorontsov , netdev@vger.kernel.org, David Miller To: Alan Stern Return-path: Received: from ogre.sisk.pl ([217.79.144.158]:52083 "EHLO ogre.sisk.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752540AbZIYMbb (ORCPT ); Fri, 25 Sep 2009 08:31:31 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Friday 25 September 2009, Alan Stern wrote: > On Thu, 24 Sep 2009, Anton Vorontsov wrote: > > > Though, there are few other issues with suspend/resume in this driver. > > The intention of calling free_irq() in suspend() was to avoid any > > possible spurious interrupts (see commit 5b039e681b8c5f30aac9cc04385 > > "3c59x PM fixes"). But, > > > > - On resume, the driver was requesting IRQ just after pci_set_master(), > > but before vortex_up() (which actually resets 3c59x chips). > > Shouldn't it be possible to reset the chip (or at least prevent it from > generating spurious IRQs) during the early-resume phase? > > > - Issuing free_irq() on a shared IRQ doesn't guarantee that a buggy > > HW won't trigger spurious interrupts in another driver that > > requested the same interrupt. So, if we want to protect from > > unexpected interrupts, then on suspend we should issue disable_irq(), > > not free_irq(). > > What if some other device shares the IRQ and still relies on receiving > interrupts when this code runs? Won't disable_irq() mess up the other > device? Ah, I overlooked the disable_irq()/enable_irq() part, which is not really necessary anyway. Anton, have you tried without that? Rafael