From mboxrd@z Thu Jan 1 00:00:00 1970 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6179FFEFB6E for ; Fri, 27 Feb 2026 17:56:29 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id BFEF36B00A5; Fri, 27 Feb 2026 12:56:28 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BC6546B00A6; Fri, 27 Feb 2026 12:56:28 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AC8B96B00A7; Fri, 27 Feb 2026 12:56:28 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 950EE6B00A5 for ; Fri, 27 Feb 2026 12:56:28 -0500 (EST) Received: from smtpin20.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 489EE160834 for ; Fri, 27 Feb 2026 17:56:28 +0000 (UTC) X-FDA: 84490991256.20.BC7F442 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by imf17.hostedemail.com (Postfix) with ESMTP id AB15840012 for ; Fri, 27 Feb 2026 17:56:26 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=none; spf=pass (imf17.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com; dmarc=pass (policy=none) header.from=arm.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1772214986; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xZk4uFbR1NTKSt90CcjBXyNBU2NiCZmzMIIkXYZlYNg=; b=BLfe1y7tdG2rb+AuDNNxEPUKtjS9k5Iq4j1lFmxCG+CWZceJiWExXs9Z7CgCfF8ZgwcNuB BCU05lwcqdx+aJtqN43dMtxX0remODm3Ip+BVqtbdEF2ssn5yyhu65BOO8XyzEKS0ys3nm lC765BA+BKjddW3WQb2bdQLd0lWI3HA= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1772214986; a=rsa-sha256; cv=none; b=2RnfRsROaZ2WHIRHI7Qp5I0+CK6LbWpxbH5EANu8KunfseUFcNnBVkytKwK69+1IA26u/u 0vz9iosuRVROp2LievX2XqfwmhBB09L+yc776SXDRL6i84bSeswgbPGjimvHsNnoflmIkJ ZcN3rPd5T2F8ITbITk8/m0swCKmtaYQ= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=none; spf=pass (imf17.hostedemail.com: domain of kevin.brodsky@arm.com designates 217.140.110.172 as permitted sender) smtp.mailfrom=kevin.brodsky@arm.com; dmarc=pass (policy=none) header.from=arm.com 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 783D814BF; Fri, 27 Feb 2026 09:56:19 -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 5F0893F73B; Fri, 27 Feb 2026 09:56:21 -0800 (PST) From: Kevin Brodsky To: linux-hardening@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Andrew Morton , Andy Lutomirski , Catalin Marinas , Dave Hansen , David Hildenbrand , Ira Weiny , Jann Horn , Jeff Xu , Joey Gouly , Kees Cook , Linus Walleij , Lorenzo Stoakes , Marc Zyngier , Mark Brown , Matthew Wilcox , Maxwell Bland , "Mike Rapoport (IBM)" , Peter Zijlstra , Pierre Langlois , Quentin Perret , Rick Edgecombe , Ryan Roberts , Thomas Gleixner , Vlastimil Babka , Will Deacon , Yang Shi , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, x86@kernel.org Subject: [PATCH v6 09/30] arm64: Initialize POR_EL1 register on cpu_resume() Date: Fri, 27 Feb 2026 17:54:57 +0000 Message-ID: <20260227175518.3728055-10-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20260227175518.3728055-1-kevin.brodsky@arm.com> References: <20260227175518.3728055-1-kevin.brodsky@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Rspam-User: X-Stat-Signature: tdxqjobxwwhrc5kszkwm9jwzc8qxaskn X-Rspamd-Queue-Id: AB15840012 X-Rspamd-Server: rspam03 X-HE-Tag: 1772214986-951652 X-HE-Meta: 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 aqPApoMg oHRanqBmD/AZNA/kgYOj0bZcKuOEO1nOm2HHsKFPsDt8qnBGuPS3igAde+Xop4prfkrCwKAa1aw0WZOMbQwpQiMVbrEBHJDWPqSTa0CbBFHHsV9Y/vReMSLhgQKoIADalD6F2Twu3Nj9v/zplS/0T2dA5TRybplxBs46FD/IKmpzYL5UmtKusd3T4QdKu1xR5nm5ADpgm4gP0RH7ZnZXHpGEnIKGaBlNAzeaET/NOSJpbxcg= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Yeoreum Yun The POR_EL1 register is reset to an unknown value after cpu_suspend(). Since POR_EL1 always holds POR_EL1_INIT when entering cpu_suspend(), initialize POR_EL1 with POR_EL1_INIT before cpu_do_resume(). Signed-off-by: Yeoreum Yun Signed-off-by: Kevin Brodsky --- arch/arm64/kernel/sleep.S | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/arch/arm64/kernel/sleep.S b/arch/arm64/kernel/sleep.S index f093cdf71be1..e0a6ad85cd24 100644 --- a/arch/arm64/kernel/sleep.S +++ b/arch/arm64/kernel/sleep.S @@ -3,6 +3,7 @@ #include #include #include +#include #include .text @@ -134,6 +135,17 @@ SYM_FUNC_START(_cpu_resume) /* load sp from context */ ldr x2, [x0, #CPU_CTX_SP] mov sp, x2 + +#ifdef CONFIG_ARM64_POE +alternative_if_not ARM64_HAS_S1POE + b .Lskip_por_set +alternative_else_nop_endif + mov_q x2, POR_EL1_INIT + msr_s SYS_POR_EL1, x2 + /* isb can be skipped since cpu_do_resume() will do it. */ +.Lskip_por_set: +#endif /* CONFIG_ARM64_POE */ + /* * cpu_do_resume expects x0 to contain context address pointer */ -- 2.51.2