From patchwork Tue Jun 4 06:34:06 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anshuman Khandual X-Patchwork-Id: 10974223 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8496276 for ; Tue, 4 Jun 2019 06:36:00 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6B8A526E90 for ; Tue, 4 Jun 2019 06:36:00 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 59FFE28346; Tue, 4 Jun 2019 06:36:00 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7CBD126E90 for ; Tue, 4 Jun 2019 06:35:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date: Subject:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To: References:List-Owner; bh=3r4FVPTgJuq8AbVUNUhlosfA+N/2dvDYSUUmvxzlD50=; b=M5g aWNrE6/Zn5acCZC82Ve+iNEvladsrZvWIXd+ZIgDt/Jn+iyZ/je9+iAJyUKjsIrE30TULa9DW+sSZ dtZI7qh7ZIiUL+VYN0B45X6Nj1V1cMP3iqtB786QM6dy2aNuCTg287DP9MSR8iGR6n5x6zq02EPd8 nzeelVLrBdS5NngzSrnIIsMOji9OgkOuYG1bY3mjGVdpDAYOmObU9PDcmigdC+Tva90yxc0PsAUp6 fkNtcU5frdnNEFd9yQJO33xo4s2s07MrccQkECNJKGY60cwbWfB+pGnEuGAW6BtI7CWd5USziID1F 0yCJskF3cuX6KI469U6ozDuz9hftXfw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hY334-0003ou-BN; Tue, 04 Jun 2019 06:35:54 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hY32z-0003nw-P7 for linux-arm-kernel@lists.infradead.org; Tue, 04 Jun 2019 06:35:51 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 750C8A78; Mon, 3 Jun 2019 23:35:46 -0700 (PDT) Received: from p8cg001049571a15.blr.arm.com (p8cg001049571a15.blr.arm.com [10.162.40.144]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id BBFB23F690; Mon, 3 Jun 2019 23:35:35 -0700 (PDT) From: Anshuman Khandual To: linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [RFC V2] mm: Generalize notify_page_fault() Date: Tue, 4 Jun 2019 12:04:06 +0530 Message-Id: <1559630046-12940-1-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190603_233549_831856_EE4E895A X-CRM114-Status: GOOD ( 21.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Michal Hocko , linux-ia64@vger.kernel.org, linux-sh@vger.kernel.org, Peter Zijlstra , Catalin Marinas , Dave Hansen , Will Deacon , Paul Mackerras , sparclinux@vger.kernel.org, Stephen Rothwell , linux-s390@vger.kernel.org, Yoshinori Sato , Michael Ellerman , x86@kernel.org, Russell King , Matthew Wilcox , Ingo Molnar , Fenghua Yu , Anshuman Khandual , Andrey Konovalov , Andy Lutomirski , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Christophe Leroy , Tony Luck , Heiko Carstens , Martin Schwidefsky , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP Similar notify_page_fault() definitions are being used by architectures duplicating much of the same code. This attempts to unify them into a single implementation, generalize it and then move it to a common place. kprobes_built_in() can detect CONFIG_KPROBES, hence notify_page_fault() need not be wrapped again within CONFIG_KPROBES. Trap number argument can now contain upto an 'unsigned int' accommodating all possible platforms. Cc: linux-arm-kernel@lists.infradead.org Cc: linux-ia64@vger.kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-s390@vger.kernel.org Cc: linux-sh@vger.kernel.org Cc: sparclinux@vger.kernel.org Cc: x86@kernel.org Cc: Andrew Morton Cc: Michal Hocko Cc: Matthew Wilcox Cc: Mark Rutland Cc: Christophe Leroy Cc: Stephen Rothwell Cc: Andrey Konovalov Cc: Michael Ellerman Cc: Paul Mackerras Cc: Russell King Cc: Catalin Marinas Cc: Will Deacon Cc: Tony Luck Cc: Fenghua Yu Cc: Martin Schwidefsky Cc: Heiko Carstens Cc: Yoshinori Sato Cc: "David S. Miller" Cc: Thomas Gleixner Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Andy Lutomirski Cc: Dave Hansen Signed-off-by: Anshuman Khandual --- Testing: - Build and boot tested on arm64 and x86 - Build tested on some other archs (arm, sparc64, alpha, powerpc etc) Changes in RFC V2: - Changed generic notify_page_fault() per Mathew Wilcox - Changed x86 to use new generic notify_page_fault() - s/must not/need not/ in commit message per Matthew Wilcox Changes in RFC V1: (https://patchwork.kernel.org/patch/10968273/) arch/arm/mm/fault.c | 22 ---------------------- arch/arm64/mm/fault.c | 22 ---------------------- arch/ia64/mm/fault.c | 22 ---------------------- arch/powerpc/mm/fault.c | 23 ++--------------------- arch/s390/mm/fault.c | 16 +--------------- arch/sh/mm/fault.c | 14 -------------- arch/sparc/mm/fault_64.c | 16 +--------------- arch/x86/mm/fault.c | 21 ++------------------- include/linux/mm.h | 1 + mm/memory.c | 16 ++++++++++++++++ 10 files changed, 23 insertions(+), 150 deletions(-) diff --git a/arch/arm/mm/fault.c b/arch/arm/mm/fault.c index 58f69fa..1bc3b18 100644 --- a/arch/arm/mm/fault.c +++ b/arch/arm/mm/fault.c @@ -30,28 +30,6 @@ #ifdef CONFIG_MMU -#ifdef CONFIG_KPROBES -static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) -{ - int ret = 0; - - if (!user_mode(regs)) { - /* kprobe_running() needs smp_processor_id() */ - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, fsr)) - ret = 1; - preempt_enable(); - } - - return ret; -} -#else -static inline int notify_page_fault(struct pt_regs *regs, unsigned int fsr) -{ - return 0; -} -#endif - /* * This is useful to dump out the page tables associated with * 'addr' in mm 'mm'. diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index a30818e..152f1f1 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -70,28 +70,6 @@ static inline const struct fault_info *esr_to_debug_fault_info(unsigned int esr) return debug_fault_info + DBG_ESR_EVT(esr); } -#ifdef CONFIG_KPROBES -static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr) -{ - int ret = 0; - - /* kprobe_running() needs smp_processor_id() */ - if (!user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, esr)) - ret = 1; - preempt_enable(); - } - - return ret; -} -#else -static inline int notify_page_fault(struct pt_regs *regs, unsigned int esr) -{ - return 0; -} -#endif - static void data_abort_decode(unsigned int esr) { pr_alert("Data abort info:\n"); diff --git a/arch/ia64/mm/fault.c b/arch/ia64/mm/fault.c index 5baeb02..64283d2 100644 --- a/arch/ia64/mm/fault.c +++ b/arch/ia64/mm/fault.c @@ -21,28 +21,6 @@ extern int die(char *, struct pt_regs *, long); -#ifdef CONFIG_KPROBES -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - int ret = 0; - - if (!user_mode(regs)) { - /* kprobe_running() needs smp_processor_id() */ - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, trap)) - ret = 1; - preempt_enable(); - } - - return ret; -} -#else -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - return 0; -} -#endif - /* * Return TRUE if ADDRESS points at a page in the kernel's mapped segment * (inside region 5, on ia64) and that page is present. diff --git a/arch/powerpc/mm/fault.c b/arch/powerpc/mm/fault.c index b5d3578..5a0d71f 100644 --- a/arch/powerpc/mm/fault.c +++ b/arch/powerpc/mm/fault.c @@ -46,26 +46,6 @@ #include #include -static inline bool notify_page_fault(struct pt_regs *regs) -{ - bool ret = false; - -#ifdef CONFIG_KPROBES - /* kprobe_running() needs smp_processor_id() */ - if (!user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, 11)) - ret = true; - preempt_enable(); - } -#endif /* CONFIG_KPROBES */ - - if (unlikely(debugger_fault_handler(regs))) - ret = true; - - return ret; -} - /* * Check whether the instruction inst is a store using * an update addressing form which will update r1. @@ -466,8 +446,9 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address, int is_write = page_fault_is_write(error_code); vm_fault_t fault, major = 0; bool must_retry = false; + int kprobe_fault = notify_page_fault(regs, 11); - if (notify_page_fault(regs)) + if (unlikely(debugger_fault_handler(regs) || kprobe_fault)) return 0; if (unlikely(page_fault_is_bad(error_code))) { diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index c220399..d317263 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c @@ -67,20 +67,6 @@ static int __init fault_init(void) } early_initcall(fault_init); -static inline int notify_page_fault(struct pt_regs *regs) -{ - int ret = 0; - - /* kprobe_running() needs smp_processor_id() */ - if (kprobes_built_in() && !user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, 14)) - ret = 1; - preempt_enable(); - } - return ret; -} - /* * Find out which address space caused the exception. * Access register mode is impossible, ignore space == 3. @@ -409,7 +395,7 @@ static inline vm_fault_t do_exception(struct pt_regs *regs, int access) */ clear_pt_regs_flag(regs, PIF_PER_TRAP); - if (notify_page_fault(regs)) + if (notify_page_fault(regs, 14)) return 0; mm = tsk->mm; diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c index 6defd2c6..94bdfcb 100644 --- a/arch/sh/mm/fault.c +++ b/arch/sh/mm/fault.c @@ -24,20 +24,6 @@ #include #include -static inline int notify_page_fault(struct pt_regs *regs, int trap) -{ - int ret = 0; - - if (kprobes_built_in() && !user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, trap)) - ret = 1; - preempt_enable(); - } - - return ret; -} - static void force_sig_info_fault(int si_signo, int si_code, unsigned long address, struct task_struct *tsk) diff --git a/arch/sparc/mm/fault_64.c b/arch/sparc/mm/fault_64.c index 8f8a604..e5557a1 100644 --- a/arch/sparc/mm/fault_64.c +++ b/arch/sparc/mm/fault_64.c @@ -38,20 +38,6 @@ int show_unhandled_signals = 1; -static inline __kprobes int notify_page_fault(struct pt_regs *regs) -{ - int ret = 0; - - /* kprobe_running() needs smp_processor_id() */ - if (kprobes_built_in() && !user_mode(regs)) { - preempt_disable(); - if (kprobe_running() && kprobe_fault_handler(regs, 0)) - ret = 1; - preempt_enable(); - } - return ret; -} - static void __kprobes unhandled_fault(unsigned long address, struct task_struct *tsk, struct pt_regs *regs) @@ -285,7 +271,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) fault_code = get_thread_fault_code(); - if (notify_page_fault(regs)) + if (notify_page_fault(regs, 0)) goto exit_exception; si_code = SEGV_MAPERR; diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 46df4c6..1790859 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -46,23 +46,6 @@ kmmio_fault(struct pt_regs *regs, unsigned long addr) return 0; } -static nokprobe_inline int kprobes_fault(struct pt_regs *regs) -{ - if (!kprobes_built_in()) - return 0; - if (user_mode(regs)) - return 0; - /* - * To be potentially processing a kprobe fault and to be allowed to call - * kprobe_running(), we have to be non-preemptible. - */ - if (preemptible()) - return 0; - if (!kprobe_running()) - return 0; - return kprobe_fault_handler(regs, X86_TRAP_PF); -} - /* * Prefetch quirks: * @@ -1280,7 +1263,7 @@ do_kern_addr_fault(struct pt_regs *regs, unsigned long hw_error_code, return; /* kprobes don't want to hook the spurious faults: */ - if (kprobes_fault(regs)) + if (notify_page_fault(regs, X86_TRAP_PF)) return; /* @@ -1311,7 +1294,7 @@ void do_user_addr_fault(struct pt_regs *regs, mm = tsk->mm; /* kprobes don't want to hook the spurious faults: */ - if (unlikely(kprobes_fault(regs))) + if (unlikely(notify_page_fault(regs, X86_TRAP_PF))) return; /* diff --git a/include/linux/mm.h b/include/linux/mm.h index 0e8834a..c5a8dcf 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1778,6 +1778,7 @@ static inline int pte_devmap(pte_t pte) } #endif +int notify_page_fault(struct pt_regs *regs, unsigned int trap); int vma_wants_writenotify(struct vm_area_struct *vma, pgprot_t vm_page_prot); extern pte_t *__get_locked_pte(struct mm_struct *mm, unsigned long addr, diff --git a/mm/memory.c b/mm/memory.c index ddf20bd..b6bae8f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -52,6 +52,7 @@ #include #include #include +#include #include #include #include @@ -141,6 +142,21 @@ static int __init init_zero_pfn(void) core_initcall(init_zero_pfn); +int __kprobes notify_page_fault(struct pt_regs *regs, unsigned int trap) +{ + int ret = 0; + + /* + * To be potentially processing a kprobe fault and to be allowed + * to call kprobe_running(), we have to be non-preemptible. + */ + if (kprobes_built_in() && !preemptible() && !user_mode(regs)) { + if (kprobe_running() && kprobe_fault_handler(regs, trap)) + ret = 1; + } + return ret; +} + #if defined(SPLIT_RSS_COUNTING) void sync_mm_rss(struct mm_struct *mm)