From patchwork Fri Mar 19 16:53:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andre Przywara X-Patchwork-Id: 405068 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=-16.8 required=3.0 tests=BAYES_00, 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 F3DC9C433E2 for ; Fri, 19 Mar 2021 16:54:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA82E61987 for ; Fri, 19 Mar 2021 16:54:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230063AbhCSQyH (ORCPT ); Fri, 19 Mar 2021 12:54:07 -0400 Received: from foss.arm.com ([217.140.110.172]:56850 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229936AbhCSQxv (ORCPT ); Fri, 19 Mar 2021 12:53:51 -0400 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 72AAEED1; Fri, 19 Mar 2021 09:53:51 -0700 (PDT) Received: from e104803-lin.cambridge.arm.com (e104803-lin.cambridge.arm.com [10.1.197.64]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 39D0A3F70D; Fri, 19 Mar 2021 09:53:50 -0700 (PDT) From: Andre Przywara To: Will Deacon , Catalin Marinas , Shuah Khan Cc: Amit Daniel Kachhap , Mark Brown , Vincenzo Frascino , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org Subject: [PATCH 06/11] kselftest/arm64: mte: Fix MTE feature detection Date: Fri, 19 Mar 2021 16:53:29 +0000 Message-Id: <20210319165334.29213-7-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.5 In-Reply-To: <20210319165334.29213-1-andre.przywara@arm.com> References: <20210319165334.29213-1-andre.przywara@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org To check whether the CPU and kernel support the MTE features we want to test, we use an (emulated) CPU ID register read. However we only check against a very particular feature version (0b0010), even though the ARM ARM promises ID register features to be backwards compatible. While this could be fixed by using ">=" instead of "==", we should actually use the explicit HWCAP2_MTE hardware capability, exposed by the kernel via the ELF auxiliary vectors. That moves this responsibility to the kernel, and fixes running the tests on machines with FEAT_MTE3 capability. Reviewed-by: Andre Przywara --- tools/testing/selftests/arm64/mte/mte_common_util.c | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) diff --git a/tools/testing/selftests/arm64/mte/mte_common_util.c b/tools/testing/selftests/arm64/mte/mte_common_util.c index 4e887dad762d..aa8a8a6b8b6d 100644 --- a/tools/testing/selftests/arm64/mte/mte_common_util.c +++ b/tools/testing/selftests/arm64/mte/mte_common_util.c @@ -291,22 +291,13 @@ int mte_switch_mode(int mte_option, unsigned long incl_mask) return 0; } -#define ID_AA64PFR1_MTE_SHIFT 8 -#define ID_AA64PFR1_MTE 2 - int mte_default_setup(void) { - unsigned long hwcaps = getauxval(AT_HWCAP); + unsigned long hwcaps2 = getauxval(AT_HWCAP2); unsigned long en = 0; int ret; - if (!(hwcaps & HWCAP_CPUID)) { - ksft_print_msg("FAIL: CPUID registers unavailable\n"); - return KSFT_FAIL; - } - /* Read ID_AA64PFR1_EL1 register */ - asm volatile("mrs %0, id_aa64pfr1_el1" : "=r"(hwcaps) : : "memory"); - if (((hwcaps >> ID_AA64PFR1_MTE_SHIFT) & MT_TAG_MASK) != ID_AA64PFR1_MTE) { + if (!(hwcaps2 & HWCAP2_MTE)) { ksft_print_msg("FAIL: MTE features unavailable\n"); return KSFT_SKIP; }