From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765281AbYD3Vhc (ORCPT ); Wed, 30 Apr 2008 17:37:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761263AbYD3VhT (ORCPT ); Wed, 30 Apr 2008 17:37:19 -0400 Received: from www.tglx.de ([62.245.132.106]:42335 "EHLO www.tglx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753052AbYD3VhR (ORCPT ); Wed, 30 Apr 2008 17:37:17 -0400 Date: Wed, 30 Apr 2008 23:36:56 +0200 (CEST) From: Thomas Gleixner To: "Eric W. Biederman" cc: =?ISO-8859-15?Q?Uwe_Kleine-K=F6nig?= , LKML , Ingo Molnar Subject: Re: [PATCH] let setup_irq reenable a shared irq In-Reply-To: Message-ID: References: <1209381171-5520-1-git-send-email-Uwe.Kleine-Koenig@digi.com> <20080428141116.GB9048@digi.com> User-Agent: Alpine 1.10 (LFD 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 30 Apr 2008, Eric W. Biederman wrote: > 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. Makes sense. > > 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 */ Your the third one to notice :) Thanks, tglx