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=-17.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 85493C2B9F8 for ; Tue, 25 May 2021 18:57:01 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 4436F600EF for ; Tue, 25 May 2021 18:57:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4436F600EF Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:List-Subscribe:List-Help: List-Post:List-Archive:List-Unsubscribe:List-Id:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=6xGomSbuY51VHvVfHY+SHO9Y9QnIin9Q4m98yQPswIk=; b=xGqIZRO9LGtM2s K0jEXOeRN0tKINh96VQEq2qb+GhCE2Ka+ODUBKaiZOvGQ6XpK1Nqniqq/J2y8rOKWb0mgZZZX+3Om /cJnWRjb49K46qg4tXnUtMPxviByGLgJ0kBJVuVVO9bdFJmpoNjRslmpWZYtMKM0h/GPC0bmj432A WCI9e4aEds0VvTYhJooBc0DdwdXMeVgY891Cq37Jx4xd/OJBWVHO2QVjI6ERL4rqIjZbxrtFnyv9v cvNVHbDBAe/pHJcA0vlpKCrKM75B75ssrONque86iE0J8ky4lIF5LdfFO41LRrq4M2aUZbztM7zpf 0+D4Pdj+sPwT5rknlbFg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1llcD5-007SxZ-Fx; Tue, 25 May 2021 18:55:23 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1llbtE-007Ie0-QH for linux-arm-kernel@lists.infradead.org; Tue, 25 May 2021 18:34:54 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 190BD169E; Tue, 25 May 2021 11:34:52 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 0947C3F719; Tue, 25 May 2021 11:34:50 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org Cc: catalin.marinas@arm.com, james.morse@arm.com, joey.gouly@arm.com, mark.rutland@arm.com, maz@kernel.org, will@kernel.org Subject: [PATCH v3 19/20] arm64: entry: don't instrument entry code with KCOV Date: Tue, 25 May 2021 19:33:01 +0100 Message-Id: <20210525183302.56293-20-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20210525183302.56293-1-mark.rutland@arm.com> References: <20210525183302.56293-1-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210525_113452_978450_81BA1A87 X-CRM114-Status: GOOD ( 10.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org The code in entry-common.c runs at exception entry and return boundaries, where portions of the kernel environment aren't available. For example, RCU may not be watching, and lockdep state may be out-of-sync with the hardware. Due to this, it is not sound to instrument this code. We generally avoid instrumentation by marking the entry functions as `noinstr`, but currently this doesn't inhibit KCOV instrumentation. Prevent this by disabling KCOV for the entire compilation unit. Signed-off-by: Mark Rutland Cc: Catalin Marinas Cc: James Morse Cc: Marc Zyngier Cc: Will Deacon --- arch/arm64/kernel/Makefile | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 6cc97730790e..294063032428 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -14,6 +14,8 @@ CFLAGS_REMOVE_return_address.o = $(CC_FLAGS_FTRACE) CFLAGS_REMOVE_syscall.o = -fstack-protector -fstack-protector-strong CFLAGS_syscall.o += -fno-stack-protector +KCOV_INSTRUMENT_entry.o := n + # Object file lists. obj-y := debug-monitors.o entry.o irq.o fpsimd.o \ entry-common.o entry-fpsimd.o process.o ptrace.o \ -- 2.11.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel