Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752992AbbHSI3p (ORCPT ); Wed, 19 Aug 2015 04:29:45 -0400 Received: from www.linutronix.de ([62.245.132.108]:59671 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752405AbbHSI3l (ORCPT ); Wed, 19 Aug 2015 04:29:41 -0400 Date: Wed, 19 Aug 2015 10:29:02 +0200 (CEST) From: Thomas Gleixner To: Jiang Liu cc: "Rafael J. Wysocki" , "Rafael J . Wysocki" , Nick Meier , "Rafael J. Wysocki" , Len Brown , Pavel Machek , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, ACPI Devel Maling List , Linux Kernel Mailing List , "linux-pm@vger.kernel.org" Subject: Re: [Patch v2] x86, ACPI, irq: Add a quirk to override SCI polarity for HyperV In-Reply-To: <55D427D3.7040103@linux.intel.com> Message-ID: References: <1439963634-12006-1-git-send-email-jiang.liu@linux.intel.com> <55D42185.1000709@linux.intel.com> <55D427D3.7040103@linux.intel.com> User-Agent: Alpine 2.11 (DEB 23 2013-08-11) 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 Content-Length: 1410 Lines: 35 On Wed, 19 Aug 2015, Jiang Liu wrote: > On 2015/8/19 14:45, Rafael J. Wysocki wrote: > > Well, the regression at hand has just shown that the assertion in the > > changelog of that commit ("no need for for special treatment for GSI > > used by ACPI SCI") does not really hold. So, if the only motivation > > for it was to get rid of one extra check in mp_unregister_gsi() > > (mp_register_gsi() still needs to check if it is dealing with the SCI > > anyway), I'd vote for reverting it. > Hi Rafael, > The motivation is to treat SCI as normal IOAPIC interrupt so > we could enforce stricter pin attribute checking. Now it does reveal > flaws in ACPI BIOS implementations, but we ran into trouble about how to > handle those flaws:( The intent of this change is entirely correct, though it seems that reality of ACPI is just different. To be on the safe side of things, I agree with Rafael that we should revert that patch instead of introducing a single platform quirk. What we can do is to emit a pr_warn() if we detect inconsistency of the SCI configuration. That way we might be able to gather information how wide spread this disease is. Thanks, tglx -- 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/