Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752950AbbGGGkt (ORCPT ); Tue, 7 Jul 2015 02:40:49 -0400 Received: from www.linutronix.de ([62.245.132.108]:58651 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751581AbbGGGkj (ORCPT ); Tue, 7 Jul 2015 02:40:39 -0400 Date: Tue, 7 Jul 2015 08:40:23 +0200 (CEST) From: Thomas Gleixner To: Al Stone cc: "Rafael J. Wysocki" , Al Stone , ACPI Devel Maling List , "linux-arm-kernel@lists.infradead.org" , "Rafael J. Wysocki" , Len Brown , Catalin Marinas , Will Deacon , Jason Cooper , Linux Kernel Mailing List , "linaro-acpi@lists.linaro.org" , Lists linaro-kernel , "patches@linaro.org" Subject: Re: [PATCH v4 0/2] Correct for ACPI 5.1->6.0 spec changes in MADT GICC entries In-Reply-To: <559B1324.8000301@redhat.com> Message-ID: References: <1436224608-27754-1-git-send-email-al.stone@linaro.org> <559B1324.8000301@redhat.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,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2380 Lines: 51 On Mon, 6 Jul 2015, Al Stone wrote: > On 07/06/2015 05:20 PM, Rafael J. Wysocki wrote: > > Hi Al, > > > > On Tue, Jul 7, 2015 at 1:16 AM, Al Stone wrote: > >> In the ACPI 5.1 version of the spec, the struct for the GICC subtable > >> (struct acpi_madt_generic_interrupt) of the MADT is 76 bytes long; in > >> ACPI 6.0, the struct is 80 bytes long. But, there is only one definition > >> in ACPICA for this struct -- and that is the 6.0 version. Hence, when > >> BAD_MADT_ENTRY() compares the struct size to the length in the GICC > >> subtable, it fails if 5.1 structs are in use, and there are systems in > >> the wild that have them. > >> > >> Note that this was found in linux-next and these patches apply against > >> that tree and the arm64 kernel tree; 4.1 does not appear to have this > >> problem since it still has the 5.1 struct definition. > >> > >> Though there is precedent in ia64 code for ignoring the changes in size, > >> this patch set instead verifies correctness. The first patch adds the > >> BAD_MADT_GICC_ENTRY() macro to check the GICC subtable only, accounting > >> for the difference in specification versions that are possible. The > >> second patch replaces BAD_MADT_ENTRY usage with the BAD_MADT_GICC_ENTRY > >> macro in arm64 code, which is currently the only architecture affected. > >> The BAD_MADT_ENTRY() will continue to work as is for all other MADT > >> subtables. > >> > >> I have tested these patches on an APM Mustang with version 1.15 firmware, > >> where the problem was found, and they fix the problem -- i.e., the system > >> will boot with either Linux 4.1 or linux-next kernels using the same ACPI > >> 5.1 compatible firmware. > > > > ACK for the series, but I guess it's better to let it go via ARM64, right? > > > > Rafael > > Thanks, Rafael. Yeah, probably so. Will has ACKd the one patch > (2/2); if he and/or Catalin ACK patch 1/2, then this seems like it > would pretty cleanly fit into ARM64. The only question would be if > Will or Catalin would want an ACK from Thomas on the irq-gic.c part > in 2/2. No objections from my side. 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/