From nobody Thu Sep 18 21:47:36 2025 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 73571C43217 for ; Thu, 1 Dec 2022 15:25:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231586AbiLAPZi (ORCPT ); Thu, 1 Dec 2022 10:25:38 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35024 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229658AbiLAPZf (ORCPT ); Thu, 1 Dec 2022 10:25:35 -0500 Received: from szxga01-in.huawei.com (szxga01-in.huawei.com [45.249.212.187]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46197AA8CC for ; Thu, 1 Dec 2022 07:25:33 -0800 (PST) Received: from dggpemm500001.china.huawei.com (unknown [172.30.72.53]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4NNKY247dfzqSn7; Thu, 1 Dec 2022 23:21:26 +0800 (CST) Received: from localhost.localdomain.localdomain (10.175.113.25) by dggpemm500001.china.huawei.com (7.185.36.107) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.31; Thu, 1 Dec 2022 23:25:30 +0800 From: Kefeng Wang To: Russell King , Marco Elver , CC: Alexander Potapenko , , Kefeng Wang Subject: [PATCH] ARM: kfence: only handle translation faults Date: Thu, 1 Dec 2022 23:42:58 +0800 Message-ID: <20221201154258.126144-1-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.35.3 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.113.25] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpemm500001.china.huawei.com (7.185.36.107) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" This is a similar fixup like arm64 does, only handle translation faults in case of unexpected kfence report when alignment faults on ARM, see more from commit 0bb1fbffc631 ("arm64: mm: kfence: only handle translation faults"). Fixes: 75969686ec0d ("ARM: 9166/1: Support KFENCE for ARM") Signed-off-by: Kefeng Wang --- arch/arm/mm/fault.c | 18 ++++++++++++++++-- arch/arm/mm/fault.h | 9 ++++++--- 2 files changed, 22 insertions(+), 5 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 46cccd6bf705..de988cba9a4b 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -105,6 +105,19 @@ static inline bool is_write_fault(unsigned int fsr) return (fsr & FSR_WRITE) && !(fsr & FSR_CM); } =20 +static inline bool is_translation_fault(unsigned int fsr) +{ + int fs =3D fsr_fs(fsr); +#ifdef CONFIG_ARM_LPAE + if ((fs & FS_MMU_NOLL_MASK) =3D=3D FS_TRANS_NOLL) + return true; +#else + if (fs =3D=3D FS_L1_TRANS || fs =3D=3D FS_L2_TRANS) + return true; +#endif + return false; +} + static void die_kernel_fault(const char *msg, struct mm_struct *mm, unsigned long addr, unsigned int fsr, struct pt_regs *regs) @@ -140,7 +153,8 @@ __do_kernel_fault(struct mm_struct *mm, unsigned long a= ddr, unsigned int fsr, if (addr < PAGE_SIZE) { msg =3D "NULL pointer dereference"; } else { - if (kfence_handle_page_fault(addr, is_write_fault(fsr), regs)) + if (is_translation_fault(fsr) && + kfence_handle_page_fault(addr, is_write_fault(fsr), regs)) return; =20 msg =3D "paging request"; @@ -208,7 +222,7 @@ static inline bool is_permission_fault(unsigned int fsr) { int fs =3D fsr_fs(fsr); #ifdef CONFIG_ARM_LPAE - if ((fs & FS_PERM_NOLL_MASK) =3D=3D FS_PERM_NOLL) + if ((fs & FS_MMU_NOLL_MASK) =3D=3D FS_PERM_NOLL) return true; #else if (fs =3D=3D FS_L1_PERM || fs =3D=3D FS_L2_PERM) diff --git a/arch/arm/mm/fault.h b/arch/arm/mm/fault.h index 83b5ab32d7a4..54927ba1fa6e 100644 --- a/arch/arm/mm/fault.h +++ b/arch/arm/mm/fault.h @@ -14,8 +14,9 @@ =20 #ifdef CONFIG_ARM_LPAE #define FSR_FS_AEA 17 +#define FS_TRANS_NOLL 0x4 #define FS_PERM_NOLL 0xC -#define FS_PERM_NOLL_MASK 0x3C +#define FS_MMU_NOLL_MASK 0x3C =20 static inline int fsr_fs(unsigned int fsr) { @@ -23,8 +24,10 @@ static inline int fsr_fs(unsigned int fsr) } #else #define FSR_FS_AEA 22 -#define FS_L1_PERM 0xD -#define FS_L2_PERM 0xF +#define FS_L1_TRANS 0x5 +#define FS_L2_TRANS 0x7 +#define FS_L1_PERM 0xD +#define FS_L2_PERM 0xF =20 static inline int fsr_fs(unsigned int fsr) { --=20 2.27.0