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=-2.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 7373CC43144 for ; Mon, 25 Jun 2018 11:00:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3A138257C1 for ; Mon, 25 Jun 2018 11:00:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3A138257C1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932400AbeFYLAN (ORCPT ); Mon, 25 Jun 2018 07:00:13 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:54588 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932340AbeFYLAL (ORCPT ); Mon, 25 Jun 2018 07:00:11 -0400 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 D710322D7; Mon, 25 Jun 2018 04:00:10 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 82FE63F73D; Mon, 25 Jun 2018 04:00:09 -0700 (PDT) From: Mark Rutland To: linux-kernel@vger.kernel.org, will.deacon@arm.com, peterz@infradead.org, boqun.feng@gmail.com Cc: Mark Rutland , Arnd Bergmann , Dmitry Vyukov Subject: [PATCHv2 05/11] atomics: instrument cmpxchg_double*() Date: Mon, 25 Jun 2018 11:59:46 +0100 Message-Id: <20180625105952.3756-6-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180625105952.3756-1-mark.rutland@arm.com> References: <20180625105952.3756-1-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We currently don't instrument cmpxchg_double() and cmpxchg_double_local() due to compilation issues reported in the past, which are supposedly related to GCC bug 72873 [1], reported when GCC 7 was not yet released. This bug only applies to x86-64, and not other architectures. While the test case for GCC bug 72873 triggers issues with released versions of GCC, the instrumented kernel code compiles fine for all configurations I have tried, and it is unclear how the two cases are/were related. As we can't reproduce the kernel build failures, let's instrument cmpxchg_double*() again. We can revisit the issue if build failures reappear. Signed-off-by: Mark Rutland Cc: Arnd Bergmann Cc: Boqun Feng Cc: Dmitry Vyukov Cc: Peter Zijlstra Cc: Will Deacon --- include/asm-generic/atomic-instrumented.h | 21 ++++++++------------- 1 file changed, 8 insertions(+), 13 deletions(-) diff --git a/include/asm-generic/atomic-instrumented.h b/include/asm-generic/atomic-instrumented.h index 53481b6eacdf..0d4b1d3dbc1e 100644 --- a/include/asm-generic/atomic-instrumented.h +++ b/include/asm-generic/atomic-instrumented.h @@ -450,23 +450,18 @@ static __always_inline bool atomic64_add_negative(s64 i, atomic64_t *v) arch_cmpxchg64_local(__ai_ptr, (old), (new)); \ }) -/* - * Originally we had the following code here: - * __typeof__(p1) ____p1 = (p1); - * kasan_check_write(____p1, 2 * sizeof(*____p1)); - * arch_cmpxchg_double(____p1, (p2), (o1), (o2), (n1), (n2)); - * But it leads to compilation failures (see gcc issue 72873). - * So for now it's left non-instrumented. - * There are few callers of cmpxchg_double(), so it's not critical. - */ #define cmpxchg_double(p1, p2, o1, o2, n1, n2) \ ({ \ - arch_cmpxchg_double((p1), (p2), (o1), (o2), (n1), (n2)); \ + typeof(p1) __ai_p1 = (p1); \ + kasan_check_write(__ai_p1, 2 * sizeof(*__ai_p1)); \ + arch_cmpxchg_double(__ai_p1, (p2), (o1), (o2), (n1), (n2)); \ }) -#define cmpxchg_double_local(p1, p2, o1, o2, n1, n2) \ -({ \ - arch_cmpxchg_double_local((p1), (p2), (o1), (o2), (n1), (n2)); \ +#define cmpxchg_double_local(p1, p2, o1, o2, n1, n2) \ +({ \ + typeof(p1) __ai_p1 = (p1); \ + kasan_check_write(__ai_p1, 2 * sizeof(*__ai_p1)); \ + arch_cmpxchg_double_local(__ai_p1, (p2), (o1), (o2), (n1), (n2)); \ }) #endif /* _LINUX_ATOMIC_INSTRUMENTED_H */ -- 2.11.0