From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794240067; b=H/KyTdmBSXLVzeuMekMlhA1vM8wZuwhkEEHr22Rsi6EuCNJ145ARsndeaJ6Tiuhl1kWn Q9l4TYWLJeuduLvXM5QfiwPhB/6HH1g6WffDc3qFdrBsqGZjdhqPLPZUUuJYcPoLOfuEm y5yhexlBu3KsUigD7l+o4wOP1JotI+hjpWmPd3x8ZKUyyK0QPoeHgz1EUytRemaAky3CF gg1QBecjrpsaIads7PBzu3DZp3IM4pEPnHqDJbUhcz8XflQU+NFZSGwl2xHfJLdMg4UMF 1S1PFHxH018SEEazZLaxwhLBl1LRBC4+rT/xK/lCXmKEfUO+i/YoqyGxvVIUBaTst2g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794240067; h=DMARC-Filter:Received:Received:DKIM-Signature:From:Date:Subject: MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id: References:In-Reply-To:To:Cc:X-Mailer:X-Developer-Signature: X-Developer-Key; bh=ySuENrGpUqjNOnPLgMFrEVBetZNZ5PFApDQ/o4nKV7Q=; b=vHW6+EaiT8AfYvY6IZZLOF/+TgFvbYK/TIl2/BoJcOFP66Kezue7WHpCgmU71wNXhz9e EF9NXuuPbx9zAktykDrn7u3avuzaLVCENT1eVJD6XB3WbPP8qkz1N7syS7A3HVH8sIHb6 sjUxAMjLExHltCVkNeEQZzs9y8ZU6PUpnXSiPszGvObgp/8dCNz0aJzcP2KRX45NE0IBF 1i809WzqGWXvLjjGG6BaCU9T7FVmplFqtjRzHwwQQahV7TWp+98+57smQq/LQMfzD0sdB 0umlqq/zEj76eTlmjBf7zlLZxs2Z3j7jkMBC2G1x2IUUlax3Ns5UwwFlmWf+gcsVQ4A== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=d4mirWSg; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CD813606EE82; Mon, 9 Nov 2026 16:01:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org CD813606EE82 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=d4mirWSg 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 2D08314BF; Mon, 9 Nov 2026 08:01:03 -0800 (PST) Received: from localhost.localdomain (e123572-lin.cambridge.arm.com [10.2.208.46]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4E7A73F632; Mon, 9 Nov 2026 08:01:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1794240066; bh=ME8w8wWVjC6kFFTloB33po9XzJ2RJqfmLmS2WG/lKf8=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=d4mirWSgxEi/JKu2hm3pp69pzDfwTMhGF+FxTJjtWYJGttTFyyMTaLtQF/oOiyJn9 h57+SBa9UM84EVZ5zS3Ap4mgf+iwD0lxSqxx1XC/tvqYGFdzzGa5mf+CX3SaCBrFAs nuOU8SkMYKk5YSjml0jU4OLWE+u4Rf23ebx0aWdw= From: Kevin Brodsky Date: Mon, 09 Nov 2026 15:58:31 +0000 Subject: [PATCH RFC v10 06/22] arm64: Disable EL2 trapping of POR_EL1 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20261109-kpkeys-v10-6-aa6c4d9603bc@arm.com> References: <20261109-kpkeys-v10-0-aa6c4d9603bc@arm.com> In-Reply-To: <20261109-kpkeys-v10-0-aa6c4d9603bc@arm.com> To: linux-hardening@vger.kernel.org Cc: Kevin Brodsky , Andrew Morton , Ard Biesheuvel , Andy Lutomirski , Catalin Marinas , Dave Hansen , "David Hildenbrand (Arm)" , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linu Cherian , Linus Walleij , Marc Zyngier , Mark Brown , Matthew Wilcox , Maxwell Bland , "Mike Rapoport (IBM)" , Peter Zijlstra , Pierre Langlois , =?utf-8?q?Pierre-Cl=C3=A9ment_Tosi?= , Quentin Perret , Rick Edgecombe , Ryan Roberts , Vlastimil Babka , Will Deacon , Yang Shi , Yeoreum Yun , linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org, Ira Weiny , Lorenzo Stoakes , Thomas Gleixner X-Mailer: b4 0.16.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1794240029; l=759; i=kevin.brodsky@arm.com; s=20260427; h=from:subject:message-id; bh=ME8w8wWVjC6kFFTloB33po9XzJ2RJqfmLmS2WG/lKf8=; b=rL512vL81TftsgVlNw/YWtwNuWTlsI6Cej/ghKNCNj73xPNjGm4Cg71LdhCcqnj1mhqyTW3HF I/KR6KaqUYRBomiLeE6iHzlv6Nr+WcGKvkmbY0SilOz0QDq5L3+GWlM X-Developer-Key: i=kevin.brodsky@arm.com; a=ed25519; pk=N2QG+eJKrvkNovwhhwJhnJ4+ScVfsGCHldmqLfcMTFs= Make sure EL2 doesn't trap kernel accesses to POR_EL1 by setting the nPOR_EL1 bit in HFGRT{R,W}_EL2. Signed-off-by: Kevin Brodsky --- arch/arm64/include/asm/el2_setup.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h index 12a500181291..a55e8d5f1eb8 100644 --- a/arch/arm64/include/asm/el2_setup.h +++ b/arch/arm64/include/asm/el2_setup.h @@ -380,7 +380,8 @@ ubfx x1, x1, #ID_AA64MMFR3_EL1_S1POE_SHIFT, #4 cbz x1, .Lskip_poe_fgt_\@ - /* Disable trapping of POR_EL0 */ + /* Disable trapping of POR_ELx */ + orr x0, x0, #HFGRTR_EL2_nPOR_EL1 orr x0, x0, #HFGRTR_EL2_nPOR_EL0 .Lskip_poe_fgt_\@: -- 2.56.0