From patchwork Wed Jan 8 10:32:49 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Brodsky X-Patchwork-Id: 13930546 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 C7222E77188 for ; Wed, 8 Jan 2025 10:53:38 +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=ntdmAnzrmKEdik76S3k2Sqibao4Hg1fMJIxwDwAihec=; b=cfcYHDW1ggrKCczyfKzXfFcmXo jNNp/YphWaoi7niZLhAiH3PQFyqYSf54zlcxbHo9NEyKt598g/nCIH3KOUel1P8wESLna8QckACLB q2SsVO27oMqKnilIdxusV27MiDOa1fr8qL9jCBQRqTl5adlV6uY94KDFQ4WMJAUfhxN6CA1Cyq068 3p5QazSr2Q2d3RvrQBXUyD90i/r9kFowDvV8eGkexLwil+5bYug2c/n5k5Ehe1rdMMJ/3dNYn72H1 SMNLdWuRnqGz4vxRv1BL+ulyYfkImqg/mS0HjtK9rnkc5A/PGJ3mS2CyyvzlwiBxDftx04xGQW2hF TcXtY/nQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tVTgk-000000084W3-2UL8; Wed, 08 Jan 2025 10:53:26 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tVTOn-000000080NI-3W8G for linux-arm-kernel@lists.infradead.org; Wed, 08 Jan 2025 10:34:55 +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 B77C613D5; Wed, 8 Jan 2025 02:35:21 -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 9D9D73F673; Wed, 8 Jan 2025 02:34:50 -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, x86@kernel.org Subject: [RFC PATCH v2 14/15] arm64: Enable kpkeys_hardened_pgtables support Date: Wed, 8 Jan 2025 10:32:49 +0000 Message-ID: <20250108103250.3188419-15-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250108103250.3188419-1-kevin.brodsky@arm.com> References: <20250108103250.3188419-1-kevin.brodsky@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250108_023453_920725_49047473 X-CRM114-Status: GOOD ( 12.25 ) 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 kpkeys_hardened_pgtables should be enabled as early as possible (if selected). It does however require kpkeys being available, which means on arm64 POE being detected and enabled. POE is a boot feature, so calling kpkeys_hardened_pgtables_enable() just after setup_boot_cpu_features() in smp_prepare_boot_cpu() is the best we can do. With that done, all the bits are in place and we can advertise support for kpkeys_hardened_pgtables by selecting ARCH_HAS_KPKEYS_HARDENED_PGTABLES if ARM64_POE is enabled. Signed-off-by: Kevin Brodsky --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/smp.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 688ffd9bf503..654e6dff9a79 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -2185,6 +2185,7 @@ config ARM64_POE select ARCH_USES_HIGH_VMA_FLAGS select ARCH_HAS_PKEYS select ARCH_HAS_KPKEYS + select ARCH_HAS_KPKEYS_HARDENED_PGTABLES 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/smp.c b/arch/arm64/kernel/smp.c index 3b3f6b56e733..074cab55f9db 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -35,6 +35,7 @@ #include #include #include +#include #include #include @@ -468,6 +469,7 @@ void __init smp_prepare_boot_cpu(void) if (system_uses_irq_prio_masking()) init_gic_priority_masking(); + kpkeys_hardened_pgtables_enable(); kasan_init_hw_tags(); /* Init percpu seeds for random tags after cpus are set up. */ kasan_init_sw_tags();