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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BB25DC4332F for ; Tue, 30 Nov 2021 11:45:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241031AbhK3Lso (ORCPT ); Tue, 30 Nov 2021 06:48:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44978 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240982AbhK3Lsi (ORCPT ); Tue, 30 Nov 2021 06:48:38 -0500 Received: from mail-wm1-x34a.google.com (mail-wm1-x34a.google.com [IPv6:2a00:1450:4864:20::34a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 77DFAC06174A for ; Tue, 30 Nov 2021 03:45:19 -0800 (PST) Received: by mail-wm1-x34a.google.com with SMTP id p12-20020a05600c1d8c00b0033a22e48203so12698468wms.6 for ; Tue, 30 Nov 2021 03:45:19 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=K7olqGN/TGjGn55ZVkEX4B3oA8fATuBzpoXYDPWo+s8=; b=clBdSB1KsdaD9LhF3VuIZRE5qDbZm9VUy7Jmjj5Uln7EAmbx9/EVEhCZVIjKZMPCK+ qVPPdLDGmjPahXUB+7UHlvMJZMoPvtMBSVaYAWCfkloYps+FrLrtPD/MSZq6V5qCVz9F HLMEG9qAzvEkT52Tvk9GFZWjZEpBWUwzTzdkavD1KWL9RmtktroFJZ7Egs8clPbPBHwn wN7uOQ716yPwwUBgmjReM4uHwoUeb55jkQFwgYZRDRcrW/uO9L1BglBLfcp2U6lDrDpx FloEFIIraKR1zTwfjZbLjFAUKKD+8XROZdOh1bjkVCNAV7lpb1p+AtLZAWaWo2nZkkq5 egZA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=K7olqGN/TGjGn55ZVkEX4B3oA8fATuBzpoXYDPWo+s8=; b=XYYvFTHvFlF1Lnb6Ef+czuKA3bPb8xRqptw+Q3Vs74I6cg4mug7TNm5nQccmPbspkM AXb5L4VwwI4wqyCyX1GijS6mw2ULl/T6jkxIpL2H7xaPXA93UWJKQHafmozir7r8Tvmb DwB/HsHc9lTEcQo3DJlgtagctlzADQk9eU4Ay1vYWsHqJK3DP0lmP7EEpn4Z8+tTxV1g ynCJwj1obBuycrc1gAp+kvsz5bd8QrufB4ZFZsJdzBTuhSVQ7NdUkOwE+vR16S60d5QP wBmuA9zIr2l5ZatxZc0rlXyYLFnSyz/i72tzvR6LxB6/Y2Ajwo2VE4MWr/mZTockS20J /XUA== X-Gm-Message-State: AOAM5309/2SVs45Ncjqs7eYdk85rMBNbHhOLfsEcAuHWyTsxZgTwYYCJ QTWw+oDT777XAD8x8OE2jHJzXrRD7w== X-Google-Smtp-Source: ABdhPJwldFqpTbfajaFXWNrJX3ZXShEvmpEyVyn9WWq1XUdWN/HHO/Y9FjyIOfXlhbvUoQlQcowRnYznoQ== X-Received: from elver.muc.corp.google.com ([2a00:79e0:15:13:86b7:11e9:7797:99f0]) (user=elver job=sendgmr) by 2002:a05:600c:4f0b:: with SMTP id l11mr625490wmq.0.1638272717644; Tue, 30 Nov 2021 03:45:17 -0800 (PST) Date: Tue, 30 Nov 2021 12:44:14 +0100 In-Reply-To: <20211130114433.2580590-1-elver@google.com> Message-Id: <20211130114433.2580590-7-elver@google.com> Mime-Version: 1.0 References: <20211130114433.2580590-1-elver@google.com> X-Mailer: git-send-email 2.34.0.rc2.393.gf8c9666880-goog Subject: [PATCH v3 06/25] kcsan, kbuild: Add option for barrier instrumentation only From: Marco Elver To: elver@google.com, "Paul E. McKenney" Cc: Alexander Potapenko , Boqun Feng , Borislav Petkov , Dmitry Vyukov , Ingo Molnar , Mark Rutland , Peter Zijlstra , Thomas Gleixner , Waiman Long , Will Deacon , kasan-dev@googlegroups.com, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, llvm@lists.linux.dev, x86@kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Source files that disable KCSAN via KCSAN_SANITIZE := n, remove all instrumentation, including explicit barrier instrumentation. With instrumentation for memory barriers, in few places it is required to enable just the explicit instrumentation for memory barriers to avoid false positives. Providing the Makefile variable KCSAN_INSTRUMENT_BARRIERS_obj.o or KCSAN_INSTRUMENT_BARRIERS (for all files) set to 'y' only enables the explicit barrier instrumentation. Signed-off-by: Marco Elver --- scripts/Makefile.lib | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index d1f865b8c0cb..ab17f7b2e33c 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -182,6 +182,11 @@ ifeq ($(CONFIG_KCSAN),y) _c_flags += $(if $(patsubst n%,, \ $(KCSAN_SANITIZE_$(basetarget).o)$(KCSAN_SANITIZE)y), \ $(CFLAGS_KCSAN)) +# Some uninstrumented files provide implied barriers required to avoid false +# positives: set KCSAN_INSTRUMENT_BARRIERS for barrier instrumentation only. +_c_flags += $(if $(patsubst n%,, \ + $(KCSAN_INSTRUMENT_BARRIERS_$(basetarget).o)$(KCSAN_INSTRUMENT_BARRIERS)n), \ + -D__KCSAN_INSTRUMENT_BARRIERS__) endif # $(srctree)/$(src) for including checkin headers from generated source files -- 2.34.0.rc2.393.gf8c9666880-goog