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=-5.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=unavailable 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 19559C43387 for ; Fri, 11 Jan 2019 18:22:57 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id EA87E21841 for ; Fri, 11 Jan 2019 18:22:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="JMAPRm9V" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EA87E21841 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date: Message-ID:From:References:To:Subject:Reply-To:Content-ID:Content-Description :Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hTgE6XxfKGC5PQUeR6VN/Mlt2x8OcIMZQTkM/SOuYRI=; b=JMAPRm9VX9h/jE jLAIclviaLWY07g4clTVRK3OXsejRiLgGt3qYrqWa8RkxC8eqcAa+rceChe9uptNGGNXoy2ekGoWh XT1Tkd2+giWWjRLV0O2MIcfntt2+/Fj2Vs5pWgTwcYCn20km9e3Y4fCCHBoHQnDLbHM5PcQ2z3GaK NOJ3LVCVTZB6m90R1R36FhYG+1DhPA3XEiRMUGUx0xe9jS1nk3FyWqiEirbzTqgrzjoU7L/tU2Pyb STDjgZwfhvIuSvQL2jEgU7qDj7++Pf6NijPHBhWukamfxbppo9gkhY8Pel0ka6feFdKv/zoyqOjDL xgjkIwk3cvEW6F2g8MzQ==; 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 1gi1SC-00043s-OI; Fri, 11 Jan 2019 18:22:48 +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 1gi1S8-00043G-QJ for linux-arm-kernel@lists.infradead.org; Fri, 11 Jan 2019 18:22:46 +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 145BC80D; Fri, 11 Jan 2019 10:22:42 -0800 (PST) Received: from [10.1.196.105] (eglon.cambridge.arm.com [10.1.196.105]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 760CD3F6CF; Fri, 11 Jan 2019 10:22:40 -0800 (PST) Subject: Re: [PATCH 1/3] arm64: kprobes: Move extable address check into arch_prepare_kprobe() To: Masami Hiramatsu References: <154502881646.30629.9938335052821665530.stgit@devbox> <154502884653.30629.3172839440883293817.stgit@devbox> <20190108113953.8bc0cc7d196ddba370377217@kernel.org> <20190109110500.b4b5049f4c67dfc85b9ced4e@kernel.org> From: James Morse Message-ID: <92c160a8-7627-0c64-ed73-df616e9c057d@arm.com> Date: Fri, 11 Jan 2019 18:22:38 +0000 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:60.0) Gecko/20100101 Thunderbird/60.3.1 MIME-Version: 1.0 In-Reply-To: <20190109110500.b4b5049f4c67dfc85b9ced4e@kernel.org> Content-Language: en-GB X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190111_102244_854584_9D99D246 X-CRM114-Status: GOOD ( 15.76 ) 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: Pratyush Anand , Catalin Marinas , Will Deacon , linux-kernel , "David A . Long" , linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On 09/01/2019 02:05, Masami Hiramatsu wrote: > On Tue, 8 Jan 2019 17:13:36 +0000 > James Morse wrote: >> On 08/01/2019 02:39, Masami Hiramatsu wrote: >>> On Thu, 3 Jan 2019 17:05:18 +0000 >>> James Morse wrote: >>>> On 17/12/2018 06:40, Masami Hiramatsu wrote: >>>>> Move extable address check into arch_prepare_kprobe() from >>>>> arch_within_kprobe_blacklist(). >>>> >>>> I'm trying to work out the pattern for what should go in the blacklist, and what >>>> should be rejected by the arch code. >>>> >>>> It seems address-ranges should be blacklisted as the contents don't matter. >>>> easy-example: the idmap text. >>> >>> Yes, more precisely, the code smaller than a function (symbol), it must be >>> rejected by arch_prepare_kprobe(), since blacklist is poplated based on >>> kallsyms. >> >> Ah, okay, so the pattern is the blacklist should only be for whole symbols, >> (which explains why its usually based on sections). > > Correct. Actually, the blacklist is generated based on the symbol info > from symbol address. > >> I see kprobe_add_ksym_blacklist() would go wrong if you give it something like: >> platform_drv_probe+0x50/0xb0, as it will log platform_drv_probe+0x50 as the >> start_addr and platform_drv_probe+0x50+0xb0 as the end. > > Yes, it expects given address is the entry of a symbol. >> But how does anything from the arch code's blacklist get into the >> kprobe_blacklist list? > > It should be done via arch_populate_kprobe_blacklist(). >> We don't have an arch_populate_kprobe_blacklist(), so rely on >> within_kprobe_blacklist() calling arch_within_kprobe_blacklist() with the >> address, as well as walking kprobe_blacklist. >> >> Is this cleanup ahead of a series that does away with >> arch_within_kprobe_blacklist() so that debugfs list is always complete? > > Right, after this cleanup, I will send arch_populate_kprobe_blacklist() > patch for arm64 and others. My plan is to move all arch_within_kprobe_blacklist() > to arch_populate_kprobe_blacklist() so that user can get more precise blacklist > via debugfs. Thanks, now it all makes sense! Reviewed-by: James Morse Could you include a paragraph like that in the cover-letter or commit-message? The 'fix' in the cover-letter subject had me looking for the bug! Thanks, James _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel