From nobody Wed Dec 17 14:21:49 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 BEB76EE49AF for ; Mon, 21 Aug 2023 12:31:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235002AbjHUMbh (ORCPT ); Mon, 21 Aug 2023 08:31:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40980 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234979AbjHUMbf (ORCPT ); Mon, 21 Aug 2023 08:31:35 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BC8C2106; Mon, 21 Aug 2023 05:31:26 -0700 (PDT) Received: from dggpemm100001.china.huawei.com (unknown [172.30.72.54]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4RTsGv1szHzVksj; Mon, 21 Aug 2023 20:29:11 +0800 (CST) Received: from localhost.localdomain (10.175.112.125) by dggpemm100001.china.huawei.com (7.185.36.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Mon, 21 Aug 2023 20:31:23 +0800 From: Kefeng Wang To: Andrew Morton , CC: , , Russell King , Catalin Marinas , Will Deacon , Huacai Chen , WANG Xuerui , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexander Gordeev , Gerald Schaefer , Heiko Carstens , Vasily Gorbik , Christian Borntraeger , Sven Schnelle , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Thomas Gleixner , Ingo Molnar , Borislav Petkov , , "H . Peter Anvin" , , , , , , , Kefeng Wang Subject: [PATCH rfc v2 09/10] loongarch: mm: add access_error() helper Date: Mon, 21 Aug 2023 20:30:55 +0800 Message-ID: <20230821123056.2109942-10-wangkefeng.wang@huawei.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20230821123056.2109942-1-wangkefeng.wang@huawei.com> References: <20230821123056.2109942-1-wangkefeng.wang@huawei.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.175.112.125] X-ClientProxiedBy: dggems705-chm.china.huawei.com (10.3.19.182) To dggpemm100001.china.huawei.com (7.185.36.93) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add access_error() to check whether vma could be accessible or not, which will be used __do_page_fault() and later vma locked based page fault. Signed-off-by: Kefeng Wang --- arch/loongarch/mm/fault.c | 30 ++++++++++++++++++++---------- 1 file changed, 20 insertions(+), 10 deletions(-) diff --git a/arch/loongarch/mm/fault.c b/arch/loongarch/mm/fault.c index 5d4c742c4bc5..2a45e9f3a485 100644 --- a/arch/loongarch/mm/fault.c +++ b/arch/loongarch/mm/fault.c @@ -126,6 +126,22 @@ static void __kprobes do_sigsegv(struct pt_regs *regs, force_sig_fault(SIGSEGV, si_code, (void __user *)address); } =20 +static inline bool access_error(unsigned int flags, struct pt_regs *regs, + unsigned long addr, struct vm_area_struct *vma) +{ + if (flags & FAULT_FLAG_WRITE) { + if (!(vma->vm_flags & VM_WRITE)) + return true; + } else { + if (!(vma->vm_flags & VM_READ) && addr !=3D exception_era(regs)) + return true; + if (!(vma->vm_flags & VM_EXEC) && addr =3D=3D exception_era(regs)) + return true; + } + + return false; +} + /* * This routine handles page faults. It determines the address, * and the problem, and then passes it off to one of the appropriate @@ -169,6 +185,8 @@ static void __kprobes __do_page_fault(struct pt_regs *r= egs, =20 if (user_mode(regs)) flags |=3D FAULT_FLAG_USER; + if (write) + flags |=3D FAULT_FLAG_WRITE; =20 perf_sw_event(PERF_COUNT_SW_PAGE_FAULTS, 1, regs, address); retry: @@ -178,16 +196,8 @@ static void __kprobes __do_page_fault(struct pt_regs *= regs, =20 si_code =3D SEGV_ACCERR; =20 - if (write) { - flags |=3D FAULT_FLAG_WRITE; - if (!(vma->vm_flags & VM_WRITE)) - goto bad_area; - } else { - if (!(vma->vm_flags & VM_READ) && address !=3D exception_era(regs)) - goto bad_area; - if (!(vma->vm_flags & VM_EXEC) && address =3D=3D exception_era(regs)) - goto bad_area; - } + if (access_error(flags, regs, vma)) + goto bad_area; =20 /* * If for any reason at all we couldn't handle the fault, --=20 2.27.0