From patchwork Thu Aug 22 01:15:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 13772396 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 9E6B4C52D7C for ; Thu, 22 Aug 2024 01:25:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=KcO1ZZIkk7irGxZ5aRTRizUv7fYLoyn9wOnJrxrxK7E=; b=eUwMDegMyNfZaP9oVVc1fazru0 KMjPSiD2/DV90ula1hzuzEOlsd4o6+38KU/nqRo3qgUPIR9L39nSnGu6bRFVCiuv8TOZc96svZYQX cPige27YJJJRVujDBL80aWEMnBzTlSsjhI4TP0afylJtn5WCdF+huvIbqaIRbOsZ8yXLw8m2bgvOW TLbtBcPsBuDtR6avZJ3FaZBC4+9bgpcTTOcfu0ttCD47u/nUCaiKj4FxcBnH5+qmrR25sxG0ROEoo xwUF3SFvs0kZtXk/riJ+0nxXdMYRp15iHhxy+/yxjfVoXQH//5shqQdZT40aTtJWPmQpiHeoSwi6h GxVy4chQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgwZg-0000000Audv-3aTQ; Thu, 22 Aug 2024 01:25:16 +0000 Received: from nyc.source.kernel.org ([147.75.193.91]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sgwT0-0000000Arix-39hV; Thu, 22 Aug 2024 01:18:24 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by nyc.source.kernel.org (Postfix) with ESMTP id EE7DFA420FE; Thu, 22 Aug 2024 01:18:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61B98C4AF18; Thu, 22 Aug 2024 01:18:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724289501; bh=sqQ+QKkmK52Q/49cSzsvA/P7PZLEWrgUxaLRjQV/ejo=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=CjJdvIq43wLukfmjToKRyHHeVQIojg0WuXILAiXT0/HpQVb+xgWlpUqmMICHCRvt1 poJ59L1QGGcL6MxMWyqKzSmlLrYwEkfmuY3llMWVch9iNGSdYe39j+QPzyESNevFD9 ewMH9HAFaQ4xQHeF7XSVDq//Ae27f60g7oETV5/TNmxiVNYu6ahUQh0nI9vAA/7PSo Nj2wk7CrHbn+/UFUd4i6EMY+0cEkpAGId3U0FgC5EEJq14N+a5naLb7QyqzIaoK4ko HgU381MB7Pi0YycD95LUxpcgbPVnWy5iVmrFOpAd21RvOr/LF/keOzZyJPLLgIHUg+ 3UrPtTfJp16Dw== From: Mark Brown Date: Thu, 22 Aug 2024 02:15:14 +0100 Subject: [PATCH v11 11/39] arm64/cpufeature: Runtime detection of Guarded Control Stack (GCS) MIME-Version: 1.0 Message-Id: <20240822-arm64-gcs-v11-11-41b81947ecb5@kernel.org> References: <20240822-arm64-gcs-v11-0-41b81947ecb5@kernel.org> In-Reply-To: <20240822-arm64-gcs-v11-0-41b81947ecb5@kernel.org> To: Catalin Marinas , Will Deacon , Jonathan Corbet , Andrew Morton , Marc Zyngier , Oliver Upton , James Morse , Suzuki K Poulose , Arnd Bergmann , Oleg Nesterov , Eric Biederman , Shuah Khan , "Rick P. Edgecombe" , Deepak Gupta , Ard Biesheuvel , Szabolcs Nagy , Kees Cook Cc: "H.J. Lu" , Paul Walmsley , Palmer Dabbelt , Albert Ou , Florian Weimer , Christian Brauner , Thiago Jung Bauermann , Ross Burton , Yury Khrustalev , Wilco Dijkstra , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, kvmarm@lists.linux.dev, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Mark Brown X-Mailer: b4 0.15-dev-37811 X-Developer-Signature: v=1; a=openpgp-sha256; l=2509; i=broonie@kernel.org; h=from:subject:message-id; bh=sqQ+QKkmK52Q/49cSzsvA/P7PZLEWrgUxaLRjQV/ejo=; b=owEBbQGS/pANAwAKASTWi3JdVIfQAcsmYgBmxpEssm61j0572jagQn51jVrKg0sQmM+kpfxtQyMu q2YtYBmJATMEAAEKAB0WIQSt5miqZ1cYtZ/in+ok1otyXVSH0AUCZsaRLAAKCRAk1otyXVSH0HenB/ 9SaBGUP0WgFMNDS/6ZR0f8D4eoA6DGU5iVT+BfZQrizL/iBEle0/DIkVgRcO1R30x2kxo4FfClzkc8 aI5PSj4d5AABqhPGa7Le2lPuu5hKBDz2Ta5aBGB1c994qpPa3F0q0HQ4cKEgHLTW8eBqYjyKMIgN/1 gavDgSQOL0Qox4HtTk5FLiatlutI7Slz7KtRR/awNPukoFlsXqXV5BbLivqOsVJX0HlC9t6YC9O1Rb vdN6j0pK3/SsY+CGIoWUWn3h6ykmoKhpwH+Q+59peF12FvFCbD9ZCNADQ9MZLNDNX8dNex7edvJAT8 LBKKQujdtKbLssSgzxABrstFIs4d2s X-Developer-Key: i=broonie@kernel.org; a=openpgp; fpr=3F2568AAC26998F9E813A1C5C3F436CA30F5D8EB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240821_181822_994991_92D7D9CB X-CRM114-Status: GOOD ( 11.02 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add a cpufeature for GCS, allowing other code to conditionally support it at runtime. Reviewed-by: Thiago Jung Bauermann Reviewed-by: Catalin Marinas Signed-off-by: Mark Brown --- arch/arm64/include/asm/cpufeature.h | 6 ++++++ arch/arm64/kernel/cpufeature.c | 9 +++++++++ arch/arm64/tools/cpucaps | 1 + 3 files changed, 16 insertions(+) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 558434267271..e0f0e4c24544 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -832,6 +832,12 @@ static inline bool system_supports_lpa2(void) return cpus_have_final_cap(ARM64_HAS_LPA2); } +static inline bool system_supports_gcs(void) +{ + return IS_ENABLED(CONFIG_ARM64_GCS) && + alternative_has_cap_unlikely(ARM64_HAS_GCS); +} + int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt); bool try_emulate_mrs(struct pt_regs *regs, u32 isn); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 646ecd3069fd..315bd7be1106 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -291,6 +291,8 @@ static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = { }; static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = { + ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_GCS), + FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_GCS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_SME_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_EL1_MPAM_frac_SHIFT, 4, 0), @@ -2870,6 +2872,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .matches = has_nv1, ARM64_CPUID_FIELDS_NEG(ID_AA64MMFR4_EL1, E2H0, NI_NV1) }, + { + .desc = "Guarded Control Stack (GCS)", + .capability = ARM64_HAS_GCS, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .matches = has_cpuid_feature, + ARM64_CPUID_FIELDS(ID_AA64PFR1_EL1, GCS, IMP) + }, {}, }; diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index ac3429d892b9..66eff95c0824 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -29,6 +29,7 @@ HAS_EVT HAS_FPMR HAS_FGT HAS_FPSIMD +HAS_GCS HAS_GENERIC_AUTH HAS_GENERIC_AUTH_ARCH_QARMA3 HAS_GENERIC_AUTH_ARCH_QARMA5