From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753660Ab2EIDUx (ORCPT ); Tue, 8 May 2012 23:20:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:4350 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753064Ab2EIDUv (ORCPT ); Tue, 8 May 2012 23:20:51 -0400 Date: Tue, 8 May 2012 23:20:36 -0400 (EDT) From: Mikulas Patocka X-X-Sender: mpatocka@file.rdu.redhat.com To: Linus Torvalds cc: Alan Cox , "James E.J. Bottomley" , Helge Deller , linux-parisc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Fix compile failure on PA-RISC In-Reply-To: Message-ID: References: <20120505115851.1fecbe50@pyramind.ukuu.org.uk> MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="185242623-1738749370-1336532840=:16707" Content-ID: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --185242623-1738749370-1336532840=:16707 Content-Type: TEXT/PLAIN; CHARSET=X-UNKNOWN Content-Transfer-Encoding: QUOTED-PRINTABLE Content-ID: On Sat, 5 May 2012, Linus Torvalds wrote: > On Sat, May 5, 2012 at 11:53 AM, Mikulas Patocka wr= ote: > > > > What NO_IRQ problem do you mean? There is > > #define NO_IRQ =A0 =A0 =A0 =A0 =A0(-1) > > in arch/parisc/include/asm/irq.h. >=20 > That's the one he means. >=20 > Switching it to zero and testing that things still work would be apprecia= ted. It works, but there is plenty of interrupt controllers on PC-RISC and I=20 can only test it on C8000 with IO-SAPIC. I don't know if irq 0 is used on= =20 some PA-RISC interrupt controller. It would be best if James Bottomley=20 tests it on his set of machines. > Much code already knows that NO_IRQ is supposed to be zero, and > there's tons of drivers that just do the (correct!) "if (!dev->irq)" > kind of thing. >=20 > Any architecture that has a non-zero NO_IRQ is basically broken. > Always has been. >=20 > Linus And what about x86? --- irq 0 is used for timer and there is void __init setup_default_timer_irq(void) { setup_irq(0, &irq0); } in arch/x86/kernel/time.c. Mikulas --185242623-1738749370-1336532840=:16707--