Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751657AbcKGTcE (ORCPT ); Mon, 7 Nov 2016 14:32:04 -0500 Received: from Galois.linutronix.de ([146.0.238.70]:53040 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751111AbcKGTcD (ORCPT ); Mon, 7 Nov 2016 14:32:03 -0500 Date: Mon, 7 Nov 2016 20:29:03 +0100 (CET) From: Thomas Gleixner To: Jon Hunter cc: Mika Westerberg , Marc Zyngier , linux-kernel@vger.kernel.org Subject: Re: BUG? genirq: irq 14 uses trigger mode 8; requested 0 In-Reply-To: Message-ID: References: <20161101130231.GD1436@lahna.fi.intel.com> <57b67069-8fc0-800f-b869-1eec3d64111f@nvidia.com> <20161101144400.GE1436@lahna.fi.intel.com> <20161107114902.GA1447@lahna.fi.intel.com> <20161107145914.GB1447@lahna.fi.intel.com> <3c6f015b-e4d3-5835-fc8e-412fa3f6a481@nvidia.com> User-Agent: Alpine 2.20 (DEB 67 2015-01-07) 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 Content-Length: 2774 Lines: 71 On Mon, 7 Nov 2016, Thomas Gleixner wrote: > No. We don't want a dummy set_type to paper over the issue. As Mika > correctly figured out that the ioapic is already configured, but it does > not propagate it to the irq descriptor. That wants to be fixed. I'll have a > look. Actually that's pointless. The ioapic code sets the type in irqdata. The type storage in the irq descriptor is a historical left over and want's to be removed. The last forgotten user of the type data in the irq descriptor is __setup_irq().... Fix below. Thanks, tglx 8<--------------------------- Subject: genirq: Use irq type from irqdata instead of irqdesc From: Thomas Gleixner Date: Mon, 07 Nov 2016 19:57:00 +0100 The type flags in the irq descriptor are there for historical reasons and only updated via irq_modify_status() or irq_set_type(). Both functions also update the type flags in irqdata. __setup_irq() is the only left over user of the type flags in the irq descriptor. If __setup_irq() is called with empty irq type flags, then the type flags are retrieved from irqdata. If an interrupt is shared, then the type flags are compared with the type flags stored in the irq descriptor. On x86 the ioapic does not have a irq_set_type() callback because the type is defined in the BIOS tables and cannot be changed. The type is stored in irqdata at setup time without updating the type data in the irq descriptor. As a result the comparison described above fails. There is no point in updating the irq descriptor flags because the only relevant storage is irqdata. Use the type flags from irqdata for both retrieval and comparison in __setup_irq() instead. Aside of that the print out in case of non matching type flags has the old and new type flags arguments flipped. Fix that as well. For correctness sake the flags stored in the irq descriptor should be removed, but this is beyond the scope of this bugfix and will be done in a later patch. Fixes: 4b357daed698 ("genirq: Look-up trigger type if not specified by caller") Reported-by: Mika Westerberg Signed-off-by: Thomas Gleixner --- kernel/irq/manage.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1341,12 +1341,12 @@ static int } else if (new->flags & IRQF_TRIGGER_MASK) { unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK; - unsigned int omsk = irq_settings_get_trigger_mask(desc); + unsigned int omsk = irqd_get_trigger_type(&desc->irq_data); if (nmsk != omsk) /* hope the handler works with current trigger mode */ pr_warn("irq %d uses trigger mode %u; requested %u\n", - irq, nmsk, omsk); + irq, omsk, nmsk); } *old_ptr = new;