From patchwork Mon Aug 21 12:30:55 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kefeng Wang X-Patchwork-Id: 1823623 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=lists.ozlabs.org (client-ip=2404:9400:2:0:216:3eff:fee1:b9f1; helo=lists.ozlabs.org; envelope-from=linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org; receiver=patchwork.ozlabs.org) Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2404:9400:2:0:216:3eff:fee1:b9f1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1)) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4RTsqD4HNfz1yYZ for ; Mon, 21 Aug 2023 22:53:44 +1000 (AEST) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4RTsqD3XM0z3dX0 for ; Mon, 21 Aug 2023 22:53:44 +1000 (AEST) X-Original-To: linuxppc-dev@lists.ozlabs.org Delivered-To: linuxppc-dev@lists.ozlabs.org Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=huawei.com (client-ip=45.249.212.188; helo=szxga02-in.huawei.com; envelope-from=wangkefeng.wang@huawei.com; receiver=lists.ozlabs.org) Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4RTsnb6Htnz3dFj for ; Mon, 21 Aug 2023 22:52:19 +1000 (AEST) 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 , 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 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 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kefeng Wang , x86@kernel.org, loongarch@lists.linux.dev, Peter Zijlstra , Catalin Marinas , Dave Hansen , "H . Peter Anvin" , WANG Xuerui , Will Deacon , Alexander Gordeev , linux-s390@vger.kernel.org, Huacai Chen , Russell King , willy@infradead.org, Ingo Molnar , Gerald Schaefer , Christian Borntraeger , Albert Ou , Vasily Gorbik , Heiko Carstens , Nicholas Piggin , Borislav Petkov , Andy Lutomirski , Paul Walmsley , Thomas Gleixner , surenb@google.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-ri scv@lists.infradead.org, Palmer Dabbelt , Sven Schnelle , linuxppc-dev@lists.ozlabs.org Errors-To: linuxppc-dev-bounces+incoming=patchwork.ozlabs.org@lists.ozlabs.org Sender: "Linuxppc-dev" 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); } +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 != exception_era(regs)) + return true; + if (!(vma->vm_flags & VM_EXEC) && addr == 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 *regs, if (user_mode(regs)) flags |= FAULT_FLAG_USER; + if (write) + flags |= FAULT_FLAG_WRITE; 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, si_code = SEGV_ACCERR; - if (write) { - flags |= FAULT_FLAG_WRITE; - if (!(vma->vm_flags & VM_WRITE)) - goto bad_area; - } else { - if (!(vma->vm_flags & VM_READ) && address != exception_era(regs)) - goto bad_area; - if (!(vma->vm_flags & VM_EXEC) && address == exception_era(regs)) - goto bad_area; - } + if (access_error(flags, regs, vma)) + goto bad_area; /* * If for any reason at all we couldn't handle the fault,