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=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT, USER_IN_DEF_DKIM_WL 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 31483C11D05 for ; Thu, 20 Feb 2020 14:19:39 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id E6E18208C4 for ; Thu, 20 Feb 2020 14:19:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="fcrj9qbV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E6E18208C4 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8E3816B0006; Thu, 20 Feb 2020 09:19:38 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 86E2C6B0007; Thu, 20 Feb 2020 09:19:38 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 75C916B0008; Thu, 20 Feb 2020 09:19:38 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0212.hostedemail.com [216.40.44.212]) by kanga.kvack.org (Postfix) with ESMTP id 5FE236B0006 for ; Thu, 20 Feb 2020 09:19:38 -0500 (EST) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id F121D33CD for ; Thu, 20 Feb 2020 14:19:37 +0000 (UTC) X-FDA: 76510713594.24.car61_36ec05df7de47 X-HE-Tag: car61_36ec05df7de47 X-Filterd-Recvd-Size: 4097 Received: from mail-wr1-f73.google.com (mail-wr1-f73.google.com [209.85.221.73]) by imf41.hostedemail.com (Postfix) with ESMTP for ; Thu, 20 Feb 2020 14:19:37 +0000 (UTC) Received: by mail-wr1-f73.google.com with SMTP id n23so1789141wra.20 for ; Thu, 20 Feb 2020 06:19:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=K2x0S2qfilo80kDLb3QBqLqDnpLdzrJVv99C/+2ox28=; b=fcrj9qbVmSDo1yXsXTHfwuQPvSdCBR3qnpXKiDLSM5d+6VtCWdYZ45sjMw/x7x7WOh JjxWNGvfD2DkD0sZNfof0OVifrKVE49nDRC/QCdhYZs/FCYCWOtb8Kt6G2popNbUDiJg D3O4XFiQ8/G77vX6Lyk0PxEJcr0neOVWUpsJdPWEXogtknL6k/wM+x1mWN+S3Q/U0scK sCk6VQIUPVYi0fgnaLnVEPPdSYEMcaBEum5ZEtIbUlL4sTj+2TKtUHgXP3A0O8+hYRzo bDa7vula0HxSISrDHLUxOZJwfp52ItUxw6yuRfh81aZ02GMOATWkQU+TxMBAUG0t435y prfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=K2x0S2qfilo80kDLb3QBqLqDnpLdzrJVv99C/+2ox28=; b=CM8Oa1hFzXD7U9wIw4ypg3SJ7xeSY/AvWDLFFJuRTAbEswANTyjUl0GVel5A2Ohp3b tinLGaLHn+f9VuGAQG/8tO8221zvZrJbvGWd4lKEZihKXn+BNBTP3JohRNee32S9fKEz cseKGvBPm/4a6hLjjOOLD7hpD2p7jLsbF6BTuUt8P20wLo1XdDyg8np93oIG/XvVqriG UGErb4t4jxNwYQ95vyIpajWmCZQmGGiw4yRxIlSKwg2Ssmfm3/7RiYy/rMrofZ4IjRkn RrTewRfgk1cAYaFqrbveJLh0TmstQccF2i2+/qbZ5gusQnWRmQl4EUPgQMN8Gml4UxgF F8WQ== X-Gm-Message-State: APjAAAXBAtRNUGgkQkcOAiPyd9SXoEgdivmpHcvqSm/twpJsPD2imoYT pjmsFbNo5QF++wgawwUJ4o8lJPBHmIg= X-Google-Smtp-Source: APXvYqxc2qIoy0IH/jrPoR7Ibv4Cs2PRgx4cVNijK0fzVzE8YjgEYHwJ/kfVnjE5iOjexvugihfWe7RhBfE= X-Received: by 2002:a5d:4d8d:: with SMTP id b13mr42894690wru.6.1582208376125; Thu, 20 Feb 2020 06:19:36 -0800 (PST) Date: Thu, 20 Feb 2020 15:19:15 +0100 In-Reply-To: <20200220141916.55455-1-glider@google.com> Message-Id: <20200220141916.55455-2-glider@google.com> Mime-Version: 1.0 References: <20200220141916.55455-1-glider@google.com> X-Mailer: git-send-email 2.25.0.265.gbab2e86ba0-goog Subject: [PATCH 2/3] stackdepot: build with -fno-builtin From: glider@google.com To: dvyukov@google.com, andreyknvl@google.com, aryabinin@virtuozzo.com, akpm@linux-foundation.org Cc: sergey.senozhatsky@gmail.com, arnd@arndb.de, linux-mm@kvack.org, vegard.nossum@oracle.com, elver@google.com, Alexander Potapenko Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Clang may replace stackdepot_memcmp() with a call to instrumented bcmp(), which is exactly what we wanted to avoid creating stackdepot_memcmp(). Building the file with -fno-builtin prevents such optimizations. This patch has been previously mailed as part of KMSAN RFC patch series. Signed-off-by: Alexander Potapenko To: Alexander Potapenko Cc: Vegard Nossum Cc: Dmitry Vyukov Cc: Marco Elver Cc: Andrey Konovalov Cc: Sergey Senozhatsky Cc: Arnd Bergmann Cc: Andrey Ryabinin Cc: linux-mm@kvack.org --- lib/Makefile | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/lib/Makefile b/lib/Makefile index 23ca78d43d247..390e90d2ee88b 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -220,6 +220,10 @@ obj-$(CONFIG_MEMREGION) += memregion.o obj-$(CONFIG_STMP_DEVICE) += stmp_device.o obj-$(CONFIG_IRQ_POLL) += irq_poll.o +# stackdepot.c should not be instrumented or call instrumented functions. +# Prevent the compiler from calling builtins like memcmp() or bcmp() from this +# file. +CFLAGS_stackdepot.o += -fno-builtin obj-$(CONFIG_STACKDEPOT) += stackdepot.o KASAN_SANITIZE_stackdepot.o := n KCOV_INSTRUMENT_stackdepot.o := n -- 2.25.0.265.gbab2e86ba0-goog