From patchwork Mon Feb 3 10:18:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 13957244 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 0DE1CC02192 for ; Mon, 3 Feb 2025 10:30:40 +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:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=1RJ6r3cxM9fgt2mbPkhm9caNHqt7aSNUg8ljSrwtyWY=; b=IZeossuUP1PjC7aKltpfBp8mMO 9bIZNgihIJ+aBkPEMLfG5tnd/BYtTOiSKsFXzrpWFTtBNiTneUVTlH2Zsv5pSXEZ6LCahUDv3fpWu Qkv+ROtrIJwsAFgAiNuy/hxEXsxkIIlhNWSBCKkerkqwKiFBz3OJyQ1/JnPHxw3Sz90HlnVznTv4T WK81UmJz3TeKq36krQLJkN/BWNmaYJBhD4gEUNRpimsvXQ0zqJNqgGEFQZnNcBq+e6gSMau8elJlj mJ5qsNUMA0dlKtr/8oeYZMv37EwiT91PPy+N6xE3BkGs/Fd1PAyD/JLhR/rHFAt3Qo0NvJuzgYRo/ Ahjnwnqw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tetio-0000000F7pQ-1HU4; Mon, 03 Feb 2025 10:30:30 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tetYr-0000000F64K-1tyi for linux-arm-kernel@bombadil.infradead.org; Mon, 03 Feb 2025 10:20:13 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Content-Transfer-Encoding:MIME-Version :References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From:Sender:Reply-To: Content-Type:Content-ID:Content-Description; bh=1RJ6r3cxM9fgt2mbPkhm9caNHqt7aSNUg8ljSrwtyWY=; b=kfWz6MzlBSfKOu36Dnog4XtQhd 1kJUWw7763nivRmrGnuqfiDNJQmhcoHohbv7hWC6KI0NsS7GhcvGP2Er6r8drnXwS0mbY8bbTm1XF PuMj3eSxN6lnHwJViDmKiAwyNjwBPMghQKTOAEqUjmHYQLA6aq29i/1kMRwzWhQke+8tFG7oSUuys DLCekwo9cuY4YGHRkWzgZOG5r/m+6lOEwiLbqViotBAyFkU9DGIsFMmxUW/n3qZ3zwdYM8TSxQsLN vI+hpBFnNIhlmkyvobNkquhlrgqNxpQCxD+WYQM8zt3VK34v9PFPw3+OQbsJnIgjUOoktuCxlyGN/ wjpIe56Q==; Received: from foss.arm.com ([217.140.110.172]) by desiato.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tetYn-0000000G3Ty-2LcE for linux-arm-kernel@lists.infradead.org; Mon, 03 Feb 2025 10:20:12 +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 3B2CE1682; Mon, 3 Feb 2025 02:20:33 -0800 (PST) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 48ED23F63F; Mon, 3 Feb 2025 02:20:05 -0800 (PST) From: Kevin Brodsky To: linux-hardening@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Andrew Morton , Mark Brown , Catalin Marinas , Dave Hansen , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Andy Lutomirski , Marc Zyngier , Peter Zijlstra , Pierre Langlois , Quentin Perret , "Mike Rapoport (IBM)" , Ryan Roberts , Thomas Gleixner , Will Deacon , Matthew Wilcox , Qi Zheng , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org Subject: [RFC PATCH v3 07/15] arm64: Enable kpkeys Date: Mon, 3 Feb 2025 10:18:31 +0000 Message-ID: <20250203101839.1223008-8-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250203101839.1223008-1-kevin.brodsky@arm.com> References: <20250203101839.1223008-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250203_102009_949709_348670E7 X-CRM114-Status: GOOD ( 13.22 ) 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 This is the final step to enable kpkeys on arm64. We enable POE at EL1 by setting TCR2_EL1.POE, and initialise POR_EL1 so that it enables access to the default pkey/POIndex (default kpkeys level). An ISB is added so that POE restrictions are enforced immediately. Having done this, we can now select ARCH_HAS_KPKEYS if ARM64_POE is enabled. Signed-off-by: Kevin Brodsky --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/cpufeature.c | 5 ++++- 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index fcdd0ed3eca8..34f15348ada8 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2186,6 +2186,7 @@ config ARM64_POE def_bool y select ARCH_USES_HIGH_VMA_FLAGS select ARCH_HAS_PKEYS + select ARCH_HAS_KPKEYS help The Permission Overlay Extension is used to implement Memory Protection Keys. Memory Protection Keys provides a mechanism for diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 4eb7c6698ae4..28b8c93c60c7 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -76,6 +76,7 @@ #include #include #include +#include #include #include @@ -2385,8 +2386,10 @@ static void cpu_enable_mops(const struct arm64_cpu_capabilities *__unused) #ifdef CONFIG_ARM64_POE static void cpu_enable_poe(const struct arm64_cpu_capabilities *__unused) { - sysreg_clear_set(REG_TCR2_EL1, 0, TCR2_EL1_E0POE); + write_sysreg_s(por_set_kpkeys_level(0, KPKEYS_LVL_DEFAULT), SYS_POR_EL1); + sysreg_clear_set(REG_TCR2_EL1, 0, TCR2_EL1_E0POE | TCR2_EL1_POE); sysreg_clear_set(CPACR_EL1, 0, CPACR_EL1_E0POE); + isb(); } #endif