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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 A2A92C83000 for ; Wed, 29 Apr 2020 21:22:58 +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 5802720731 for ; Wed, 29 Apr 2020 21:22:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="BRcgX9Vi"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="pPkBDc+Y" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5802720731 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=OV3BgE828X2JQBopywMb/ij/KsrH3XB9KhWOac625oQ=; b=BRcgX9Vip9CPU4 ickgir9Yi4ohXJi6sDwdyNHdDSrFKf7al49h0W6nJHiDnfIGIntHgJReFG/udhubi2ISVBWO5D436 T6f7Css8/fsVHr07HqhrQDOgt7ZDzTTGEgWfe0Gcpqvh17IzA3515Kewu4KQ+uWgv4q6A9Jy3Jzfq Nmo3COD0UOhLV/TVTnejGanLWA8m6wBuLwAabK1/XTq0SlBOpPP79+oqQRPrmBzzedfceKATLwaor 5OZRWqBfQ+Qg/b34rcOD7IzuD2CX828nk2ozSNM1E2DvE87PXuyUjTFdhofFFq2v4YlMsBJT7SnGT cQYc8NdY4/9LiQs0Lsbw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jTuAQ-0002Cl-BP; Wed, 29 Apr 2020 21:22:54 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jTu7q-0007o2-D2 for linux-arm-kernel@lists.infradead.org; Wed, 29 Apr 2020 21:20:20 +0000 Received: from localhost (fw-tnat.cambridge.arm.com [217.140.96.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 31BC02076B; Wed, 29 Apr 2020 21:20:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588195212; bh=VQr2ovqTsWd+iI6IAwsK5Ry6njw45gkzahinrH2kPjc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=pPkBDc+YCvdJDLaq5bnbB2aRI0z7AAsQvARpMCOOGiKwAqWTsHBRHCnkHKLjzO1B7 kbsH0XcHZvGZxjCreumPFOfROHxYUdO+u6u9JtvI+kvIuslsaBXduJhq3BpAPNR9Wz 85UxQh1TmHypoxwx7v+FBq4eTriu01Cw/nAzIaYg= From: Mark Brown To: Vincenzo Frascino , Will Deacon , Catalin Marinas Subject: [PATCH v2 06/10] arm64: bti: Provide Kconfig for kernel mode BTI Date: Wed, 29 Apr 2020 22:16:37 +0100 Message-Id: <20200429211641.9279-7-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200429211641.9279-1-broonie@kernel.org> References: <20200429211641.9279-1-broonie@kernel.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200429_142014_596608_03A47B85 X-CRM114-Status: GOOD ( 11.37 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Brown , Kees Cook , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Now that all the code is in place provide a Kconfig option allowing users to enable BTI for the kernel if their toolchain supports it, defaulting it on since this has security benefits. This is a separate configuration option since we currently don't support secondary CPUs that lack BTI if the boot CPU supports it. Code generation issues mean that current GCC 9 versions are not able to produce usable BTI binaries so we disable support for building with GCC versions prior to 10, once a fix is backported to GCC 9 the dependencies will be updated. Signed-off-by: Mark Brown --- arch/arm64/Kconfig | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6f199d8146d4..f3de1c115fc0 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1610,6 +1610,24 @@ config ARM64_BTI BTI, such binaries can still run, but you get no additional enforcement of branch destinations. +config ARM64_BTI_KERNEL + bool "Use Branch Target Identification for kernel" + default y + depends on ARM64_BTI + depends on ARM64_PTR_AUTH + depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI + depends on !CC_IS_GCC || GCC_VERSION >= 100000 + depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS) + help + Build the kernel with Branch Target Identification annotations + and enable enforcement of this for kernel code. When this option + is enabled and the system supports BTI all kernel code including + modular code must have BTI enabled. + +config CC_HAS_BRANCH_PROT_PAC_RET_BTI + # GCC 9 or later, clang 8 or later + def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti) + config ARM64_E0PD bool "Enable support for E0PD" default y -- 2.20.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel