From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F24D3C282C3 for ; Thu, 24 Jan 2019 18:54:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CCC33218CD for ; Thu, 24 Jan 2019 18:54:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728468AbfAXSyb (ORCPT ); Thu, 24 Jan 2019 13:54:31 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:34432 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725913AbfAXSyb (ORCPT ); Thu, 24 Jan 2019 13:54:31 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id F2FBDEBD; Thu, 24 Jan 2019 10:54:30 -0800 (PST) Received: from brain-police.canterbury.ac.nz (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 936703F237; Thu, 24 Jan 2019 10:54:29 -0800 (PST) From: Will Deacon To: gregkh@linuxfoundation.org Cc: linux-kernel@vger.kernel.org, Dave Airlie , stable@vger.kernel.org, Will Deacon Subject: [PATCH stable-4.9.y] locking/qspinlock: Pull in asm/byteorder.h to ensure correct endianness Date: Thu, 24 Jan 2019 18:54:15 +0000 Message-Id: <20190124185415.29830-1-will.deacon@arm.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Dave Airlie This commit is not required upstream, but is required for the 4.9.y stable series. Upstream commit 101110f6271c ("Kbuild: always define endianess in kconfig.h") ensures that either __LITTLE_ENDIAN or __BIG_ENDIAN is defined to reflect the endianness of the target CPU architecture regardless of whether or not has been #included. The upstream definition of 'struct qspinlock' relies on this property. Unfortunately, the 4.9.y stable series does not provide this guarantee, so the 'spin_unlock()' routine can erroneously treat the underlying lockword as big-endian on little-endian architectures using native qspinlock (i.e. x86_64 without PV) if the caller has not included . This can lead to hangs such as the one in 'i915_gem_request()' reported via bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=202063 Fix the issue by ensuring that is #included in , where 'struct qspinlock' is defined. Cc: # 4.9 Signed-off-by: Dave Airlie [will: wrote commit message] Signed-off-by: Will Deacon --- include/asm-generic/qspinlock_types.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/asm-generic/qspinlock_types.h b/include/asm-generic/qspinlock_types.h index d10f1e7d6ba8..6503e96710fa 100644 --- a/include/asm-generic/qspinlock_types.h +++ b/include/asm-generic/qspinlock_types.h @@ -18,6 +18,8 @@ #ifndef __ASM_GENERIC_QSPINLOCK_TYPES_H #define __ASM_GENERIC_QSPINLOCK_TYPES_H +#include + /* * Including atomic.h with PARAVIRT on will cause compilation errors because * of recursive header file incluson via paravirt_types.h. So don't include -- 2.17.1