From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751825Ab1ITVlG (ORCPT ); Tue, 20 Sep 2011 17:41:06 -0400 Received: from www.linutronix.de ([62.245.132.108]:46519 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751194Ab1ITVlE (ORCPT ); Tue, 20 Sep 2011 17:41:04 -0400 Date: Tue, 20 Sep 2011 23:41:02 +0200 (CEST) From: Thomas Gleixner To: Sebastian Andrzej Siewior cc: linux-kernel@vger.kernel.org, Grant Likely Subject: Re: [PATCH] irq/irqdomain: change bail out condition for irq_domain_add() In-Reply-To: <1316554589-24393-1-git-send-email-bigeasy@linutronix.de> Message-ID: References: <1316554589-24393-1-git-send-email-bigeasy@linutronix.de> User-Agent: Alpine 2.02 (LFD 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 20 Sep 2011, Sebastian Andrzej Siewior wrote: > I tried to convert x86 to this infrastructure and I run into > |BUG: unable to handle kernel NULL pointer dereference at 00000014 > > (d || d->domain) is kinda bogus because if d is NULL it will check for > d->domain which should fail. It seems that the code needs the irq_data > to be present and there should be no irq_domain set yet. This patch does > this. > > My convert to this infrastructure still does not work with this patch > but I have enough for today. > > Cc: Grant Likely > Signed-off-by: Sebastian Andrzej Siewior > --- > kernel/irq/irqdomain.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c > index d5828da..213089b 100644 > --- a/kernel/irq/irqdomain.c > +++ b/kernel/irq/irqdomain.c > @@ -29,7 +29,7 @@ void irq_domain_add(struct irq_domain *domain) > */ > for (hwirq = 0; hwirq < domain->nr_irq; hwirq++) { > d = irq_get_irq_data(irq_domain_to_irq(domain, hwirq)); > - if (d || d->domain) { > + if (!d || d->domain) { > /* things are broken; just report, don't clean up */ > WARN(1, "error: irq_desc already assigned to a domain"); > return; I've already queued a similar fix in tip/irq/urgent Thanks, tglx