Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753537AbYJUIb0 (ORCPT ); Tue, 21 Oct 2008 04:31:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751755AbYJUIbS (ORCPT ); Tue, 21 Oct 2008 04:31:18 -0400 Received: from gate.crashing.org ([63.228.1.57]:50141 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751686AbYJUIbR (ORCPT ); Tue, 21 Oct 2008 04:31:17 -0400 Subject: Re: Bug in "genirq: record trigger type" From: Benjamin Herrenschmidt Reply-To: benh@kernel.crashing.org To: David Brownell Cc: Linux Kernel Mailing List , Ingo Molnar , Thomas Gleixner , Linus Torvalds , linuxppc-dev list In-Reply-To: <200810210101.19741.david-b@pacbell.net> References: <200810202205.m9KM5une024759@hera.kernel.org> <1224570730.7654.242.camel@pasglop> <200810210101.19741.david-b@pacbell.net> Content-Type: text/plain Date: Tue, 21 Oct 2008 19:29:54 +1100 Message-Id: <1224577794.7654.253.camel@pasglop> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1400 Lines: 38 On Tue, 2008-10-21 at 01:01 -0700, David Brownell wrote: > > I'm a bit more curious about another potential issue though ... as > described in the patch comment: > > - Make set_irq_type() usage match request_irq() usage: > * IRQ_TYPE_NONE should be a NOP; succeed, so irq_chip methods > won't have to handle that case any more (many do it wrong). > > It might be a bit more accurate to say irq_chip.set_type() methods > are *inconsistent* in handling IRQ_TYPE_NONE. Previously the > set_irq_type() method would pass that down to irq_chip code. > > I had observed two behaviors, but I thought I observed a third one > in some of the PowerPC code: > > (1) ignore it ... matching request_irq() usage > (2) return an error ... nasty > (3) assign some irq_chip-specific trigger mode > > That third behavior might cause a bit of trouble, but I think > it was only used during platform init. Someone more attuned > to PowerPC might want to check ... Ok, I wrote a lot of the port of powerpc stuff to genirq so I supposed I'm the person to do that sweep :-) I'll have a look tomorrow. Thanks for the heads up, Cheers, Ben. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/