From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9B8D71AA7A6; Tue, 17 Mar 2026 17:21:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773768071; cv=none; b=KHoxRLigW+vqkffabmFL9gtG4EsU6RvO5W/4eAKPUGBPzKodaQli7hC2AiNNFtWgXtV/N++BqIwPiLnZBwxzuJSWENbJwMZqeNIsXoJ98OllvSsNeBJ/UQb4fNcPMc/r3PuXkdk+s4UFisucBG7HKamL+HbsC7f7Kxs01nBZK4I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773768071; c=relaxed/simple; bh=R0oY3W65lb2I8UGcVAzGv1a64xbpOUgeaYIzFkzej5k=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XNsHdMSz73fQVcF0FL3PGhsi99CF7ccVEn2dFOyO/19TineWlkXOSDSVovTilDUtmqKac+DsI3uWinFZNI1zphY7vl6yMz5XAIlEwfv80IfIrU89zBCAXih/5rSNRchUTZOgyJ7Mc9BElWxQg1mTfWcous2bbDFcStsH9XG0AZ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BXTA4kUP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="BXTA4kUP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 93B56C4CEF7; Tue, 17 Mar 2026 17:21:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1773768071; bh=R0oY3W65lb2I8UGcVAzGv1a64xbpOUgeaYIzFkzej5k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BXTA4kUPTInHpyE/rRd0W54BZ74u9l2++CaqxrURHhsA9lRC0SqTcXhVheUlhcOLl uwrKaFFOMU7/sVZKW+iuwm0IUjboebPBbgISXtMcaXLSBP1KCYEZWTNO3teDMAmdLw Zib+V/aCTry6ZRNFudsYBhKg2cgk07K3dPCy/DQw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Catalin Marinas , Jianpeng Chang , Will Deacon , "Huang, Ying" , Guenter Roeck Subject: [PATCH 6.18 225/333] arm64: mm: Add PTE_DIRTY back to PAGE_KERNEL* to fix kexec/hibernation Date: Tue, 17 Mar 2026 17:34:14 +0100 Message-ID: <20260317163007.708170404@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260317162959.345812316@linuxfoundation.org> References: <20260317162959.345812316@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Catalin Marinas commit c25c4aa3f79a488cc270507935a29c07dc6bddfc upstream. Commit 143937ca51cc ("arm64, mm: avoid always making PTE dirty in pte_mkwrite()") changed pte_mkwrite_novma() to only clear PTE_RDONLY when PTE_DIRTY is set. This was to allow writable-clean PTEs for swap pages that haven't actually been written. However, this broke kexec and hibernation for some platforms. Both go through trans_pgd_create_copy() -> _copy_pte(), which calls pte_mkwrite_novma() to make the temporary linear-map copy fully writable. With the updated pte_mkwrite_novma(), read-only kernel pages (without PTE_DIRTY) remain read-only in the temporary mapping. While such behaviour is fine for user pages where hardware DBM or trapping will make them writeable, subsequent in-kernel writes by the kexec relocation code will fault. Add PTE_DIRTY back to all _PAGE_KERNEL* protection definitions. This was the case prior to 5.4, commit aa57157be69f ("arm64: Ensure VM_WRITE|VM_SHARED ptes are clean by default"). With the kernel linear-map PTEs always having PTE_DIRTY set, pte_mkwrite_novma() correctly clears PTE_RDONLY. Fixes: 143937ca51cc ("arm64, mm: avoid always making PTE dirty in pte_mkwrite()") Signed-off-by: Catalin Marinas Cc: stable@vger.kernel.org Reported-by: Jianpeng Chang Link: https://lore.kernel.org/r/20251204062722.3367201-1-jianpeng.chang.cn@windriver.com Cc: Will Deacon Cc: Huang, Ying Cc: Guenter Roeck Reviewed-by: Huang Ying Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- arch/arm64/include/asm/pgtable-prot.h | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -50,11 +50,11 @@ #define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL)) -#define _PAGE_KERNEL (PROT_NORMAL) -#define _PAGE_KERNEL_RO ((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY) -#define _PAGE_KERNEL_ROX ((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY) -#define _PAGE_KERNEL_EXEC (PROT_NORMAL & ~PTE_PXN) -#define _PAGE_KERNEL_EXEC_CONT ((PROT_NORMAL & ~PTE_PXN) | PTE_CONT) +#define _PAGE_KERNEL (PROT_NORMAL | PTE_DIRTY) +#define _PAGE_KERNEL_RO ((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY | PTE_DIRTY) +#define _PAGE_KERNEL_ROX ((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY | PTE_DIRTY) +#define _PAGE_KERNEL_EXEC ((PROT_NORMAL & ~PTE_PXN) | PTE_DIRTY) +#define _PAGE_KERNEL_EXEC_CONT ((PROT_NORMAL & ~PTE_PXN) | PTE_CONT | PTE_DIRTY) #define _PAGE_SHARED (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) #define _PAGE_SHARED_EXEC (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE)