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=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 7F7B9C433E0 for ; Mon, 8 Feb 2021 10:18:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4204B64E8A for ; Mon, 8 Feb 2021 10:18:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232237AbhBHKSj (ORCPT ); Mon, 8 Feb 2021 05:18:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:59524 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230360AbhBHKEz (ORCPT ); Mon, 8 Feb 2021 05:04:55 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (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 DC4AC64E87; Mon, 8 Feb 2021 10:04:13 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1l93JA-00Ck14-4f; Mon, 08 Feb 2021 09:58:16 +0000 From: Marc Zyngier To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org Cc: Catalin Marinas , Will Deacon , Mark Rutland , David Brazdil , Alexandru Elisei , Ard Biesheuvel , Jing Zhang , Ajay Patil , Prasad Sodagudi , Srinivas Ramana , Hector Martin , James Morse , Julien Thierry , Suzuki K Poulose , kernel-team@android.com Subject: [PATCH v7 22/23] arm64: cpufeatures: Allow disabling of Pointer Auth from the command-line Date: Mon, 8 Feb 2021 09:57:31 +0000 Message-Id: <20210208095732.3267263-23-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210208095732.3267263-1-maz@kernel.org> References: <20210208095732.3267263-1-maz@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, dbrazdil@google.com, alexandru.elisei@arm.com, ardb@kernel.org, jingzhangos@google.com, pajay@qti.qualcomm.com, psodagud@codeaurora.org, sramana@codeaurora.org, marcan@marcan.st, james.morse@arm.com, julien.thierry.kdev@gmail.com, suzuki.poulose@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order to be able to disable Pointer Authentication at runtime, whether it is for testing purposes, or to work around HW issues, let's add support for overriding the ID_AA64ISAR1_EL1.{GPI,GPA,API,APA} fields. This is further mapped on the arm64.nopauth command-line alias. Signed-off-by: Marc Zyngier Reviewed-by: Catalin Marinas Acked-by: David Brazdil Tested-by: Srinivas Ramana --- Documentation/admin-guide/kernel-parameters.txt | 3 +++ arch/arm64/include/asm/cpufeature.h | 1 + arch/arm64/kernel/cpufeature.c | 4 +++- arch/arm64/kernel/idreg-override.c | 16 ++++++++++++++++ 4 files changed, 23 insertions(+), 1 deletion(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 7599fd0f1ad7..f9cb28a39bd0 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -376,6 +376,9 @@ arm64.nobti [ARM64] Unconditionally disable Branch Target Identification support + arm64.nopauth [ARM64] Unconditionally disable Pointer Authentication + support + ataflop= [HW,M68k] atarimouse= [HW,MOUSE] Atari Mouse diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 30917b9a760b..61177bac49fa 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -820,6 +820,7 @@ static inline unsigned int get_vmid_bits(u64 mmfr1) extern struct arm64_ftr_override id_aa64mmfr1_override; extern struct arm64_ftr_override id_aa64pfr1_override; +extern struct arm64_ftr_override id_aa64isar1_override; u32 get_kvm_ipa_limit(void); void dump_cpu_features(void); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 7fbeab497adb..3bce87a03717 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -559,6 +559,7 @@ static const struct arm64_ftr_bits ftr_raz[] = { struct arm64_ftr_override __ro_after_init id_aa64mmfr1_override; struct arm64_ftr_override __ro_after_init id_aa64pfr1_override; +struct arm64_ftr_override __ro_after_init id_aa64isar1_override; static const struct __ftr_reg_entry { u32 sys_id; @@ -604,7 +605,8 @@ static const struct __ftr_reg_entry { /* Op1 = 0, CRn = 0, CRm = 6 */ ARM64_FTR_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0), - ARM64_FTR_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1), + ARM64_FTR_REG_OVERRIDE(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1, + &id_aa64isar1_override), /* Op1 = 0, CRn = 0, CRm = 7 */ ARM64_FTR_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0), diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index d691e9015c62..dffb16682330 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -46,6 +46,18 @@ static const struct ftr_set_desc pfr1 __initconst = { }, }; +static const struct ftr_set_desc isar1 __initconst = { + .name = "id_aa64isar1", + .override = &id_aa64isar1_override, + .fields = { + { "gpi", ID_AA64ISAR1_GPI_SHIFT }, + { "gpa", ID_AA64ISAR1_GPA_SHIFT }, + { "api", ID_AA64ISAR1_API_SHIFT }, + { "apa", ID_AA64ISAR1_APA_SHIFT }, + {} + }, +}; + extern struct arm64_ftr_override kaslr_feature_override; static const struct ftr_set_desc kaslr __initconst = { @@ -62,6 +74,7 @@ static const struct ftr_set_desc kaslr __initconst = { static const struct ftr_set_desc * const regs[] __initconst = { &mmfr1, &pfr1, + &isar1, &kaslr, }; @@ -72,6 +85,9 @@ static const struct { { "kvm-arm.mode=nvhe", "id_aa64mmfr1.vh=0" }, { "kvm-arm.mode=protected", "id_aa64mmfr1.vh=0" }, { "arm64.nobti", "id_aa64pfr1.bt=0" }, + { "arm64.nopauth", + "id_aa64isar1.gpi=0 id_aa64isar1.gpa=0 " + "id_aa64isar1.api=0 id_aa64isar1.apa=0" }, { "nokaslr", "kaslr.disabled=1" }, }; -- 2.29.2