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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 9E9F8C4332F for ; Fri, 9 Dec 2022 11:17:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5cfIxkQb+Pto0rEAN5ptCpOmuKmqvZ8VsJG2BTT4prM=; b=SnfXB07Se+R0Lg LhLNfWSoB3wgqHQxwswelFQdilsWfjUFmWkEAroPGwlo1wKc00bNVmjABtWADsAM7ttUg91pJ7z6s igmk/gLlkJYt+H5MwfKwcUlokD6VwBErVQmJ5Uaj1d97AVU3hluOm49+t8SWZwC5DiwVHtL9aJ4vc G5nc63AbZwnl541CQ+nXDRieLVxW8PL3nfG2Czn2On5dIOtNxT86xFgInl19KN6GJQDw9UISPFBTe LdC0Dm8u5YI11e7+rIpUJhnscq4t48ePp8zwOZ6Bc/KudNjDi3JpNza3ZunzuZAvSJ3QO9fsUu7sR KL/i/jqqcooMsA4u/7hw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p3bMy-0075DJ-83; Fri, 09 Dec 2022 11:16:44 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p3bMt-0075Bc-HW for linux-arm-kernel@lists.infradead.org; Fri, 09 Dec 2022 11:16:40 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0AFCA23A; Fri, 9 Dec 2022 03:16:45 -0800 (PST) Received: from FVFF77S0Q05N (unknown [10.57.39.232]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C089A3F73B; Fri, 9 Dec 2022 03:16:36 -0800 (PST) Date: Fri, 9 Dec 2022 11:16:34 +0000 From: Mark Rutland To: Masami Hiramatsu Cc: Catalin Marinas , Will Deacon , Mark Brown , Kalesh Singh , Marc Zyngier , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Sandeepa Prabhu Subject: Re: [PATCH v2 1/3] arm64: Prohibit instrumentation on arch_stack_walk() Message-ID: References: <166994750386.439920.1754385804350980158.stgit@devnote3> <166994751368.439920.3236636557520824664.stgit@devnote3> <20221206094137.389e4c374f4be060af19f33a@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20221206094137.389e4c374f4be060af19f33a@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221209_031639_651900_CE012915 X-CRM114-Status: GOOD ( 14.47 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Dec 06, 2022 at 09:41:37AM +0900, Masami Hiramatsu wrote: > On Fri, 2 Dec 2022 13:17:30 +0000 > Mark Rutland wrote: > > I had a go at testing this patch, and it fixes the crash with the reproducer > > above, but there are plenty of other instances in stacktrace.c that lead to the > > same sort of crash, e.g. > > > > # echo p stackinfo_get_task >> ${TRACEFS}/kprobe_events > > # echo 1 > ${TRACEFS}/events/kprobes/enable > > Oops, thanks for pointing! Hmm, I thought stackinfo_get_task() is an > inlined function usually. Maybe we should make it nokprobe_inline. > But this is just one case. I need to scan all symbols to trace... FWIW, due to other instrumentation issues I've started doing a larger noinstr cleanup on arm64 which should address this, as fixing this properly involves also modifying a bunch of underlying helpers (e.g. preempt_count()). I can Cc you when sending that out, if you'd like? That'll probably be in the new year. Thanks, Mark. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel