From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 243C3C282CE for ; Tue, 4 Jun 2019 08:12:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 00ECD24D92 for ; Tue, 4 Jun 2019 08:12:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727159AbfFDIMH (ORCPT ); Tue, 4 Jun 2019 04:12:07 -0400 Received: from foss.arm.com ([217.140.101.70]:37106 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726637AbfFDIMG (ORCPT ); Tue, 4 Jun 2019 04:12:06 -0400 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 22F87A78; Tue, 4 Jun 2019 01:12:06 -0700 (PDT) Received: from [10.162.40.144] (p8cg001049571a15.blr.arm.com [10.162.40.144]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 82BA43F246; Tue, 4 Jun 2019 01:11:55 -0700 (PDT) Subject: Re: [RFC V2] mm: Generalize notify_page_fault() To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, x86@kernel.org, Andrew Morton , Michal Hocko , Matthew Wilcox , Mark Rutland , Christophe Leroy , Stephen Rothwell , Andrey Konovalov , Michael Ellerman , Paul Mackerras , Russell King , Catalin Marinas , Will Deacon , Tony Luck , Fenghua Yu , Martin Schwidefsky , Heiko Carstens , Yoshinori Sato , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Andy Lutomirski , Dave Hansen References: <1559630046-12940-1-git-send-email-anshuman.khandual@arm.com> <20190604065401.GE3402@hirez.programming.kicks-ass.net> From: Anshuman Khandual Message-ID: Date: Tue, 4 Jun 2019 13:42:10 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190604065401.GE3402@hirez.programming.kicks-ass.net> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/04/2019 12:24 PM, Peter Zijlstra wrote: > On Tue, Jun 04, 2019 at 12:04:06PM +0530, Anshuman Khandual wrote: >> 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; >> +} > > That thing should be called kprobe_page_fault() or something, > notify_page_fault() is a horribly crap name for this function. Agreed. kprobe_page_fault() sounds good.