From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765566AbYD3VTp (ORCPT ); Wed, 30 Apr 2008 17:19:45 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757523AbYD3VTh (ORCPT ); Wed, 30 Apr 2008 17:19:37 -0400 Received: from out02.mta.xmission.com ([166.70.13.232]:40583 "EHLO out02.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756487AbYD3VTf (ORCPT ); Wed, 30 Apr 2008 17:19:35 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Thomas Gleixner Cc: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= , LKML , Ingo Molnar References: <1209381171-5520-1-git-send-email-Uwe.Kleine-Koenig@digi.com> <20080428141116.GB9048@digi.com> Date: Wed, 30 Apr 2008 14:19:05 -0700 In-Reply-To: (Thomas Gleixner's message of "Mon, 28 Apr 2008 18:10:30 +0200 (CEST)") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/21.4 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-SA-Exim-Connect-IP: 24.130.11.59 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-DCC: XMission; sa01 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Report: * -1.8 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% * [score: 0.0000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa01 1397; Body=1 Fuz1=1 Fuz2=1] * 0.0 XM_SPF_Neutral SPF-Neutral Subject: Re: [PATCH] let setup_irq reenable a shared irq X-SA-Exim-Version: 4.2 (built Thu, 03 Mar 2005 10:44:12 +0100) X-SA-Exim-Scanned: Yes (on mgr1.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thomas Gleixner writes: > > Subject: genirq: reenable a nobody cared disabled irq when a new driver arrives > From: Thomas Gleixner > Date: Mon, 28 Apr 2008 17:01:56 +0200 > > Uwe Kleine-Koenig has some strange hardware where one of the shared > interrupts can be asserted during boot before the appropriate driver > loads. Requesting the shared irq line from another driver results in a > spurious interrupt storm which finally disables the interrupt line. > > I have seen similar behaviour on resume before (the hardware does not > work anymore so I can not verify) and this spurious irq issue is > raised on a regular base in bugreports. This case also happens on a regular basis in kdump kernels where we deliberately don't shutdown the hardware before starting the new kernel. This patch should reduce the need for using irqpoll in that situation by a small amount. > Index: linux-2.6/include/linux/irq.h > =================================================================== > --- linux-2.6.orig/include/linux/irq.h > +++ linux-2.6/include/linux/irq.h > @@ -61,6 +61,7 @@ typedef void (*irq_flow_handler_t)(unsig > #define IRQ_WAKEUP 0x00100000 /* IRQ triggers system wakeup */ > #define IRQ_MOVE_PENDING 0x00200000 /* need to re-target IRQ destination */ > #define IRQ_NO_BALANCING 0x00400000 /* IRQ is excluded from balancing */ > +#define IRQ_SPURIOUS_DISABLED 0x00400000 /* IRQ was disabled by the spurious trap */ Looks like a duplicate define here. Don't you want: +#define IRQ_SPURIOUS_DISABLED 0x00800000 /* IRQ was disabled by the spurious trap */