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=-3.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS autolearn=no 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 2AA75C2D0A3 for ; Wed, 4 Nov 2020 00:31:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A9E3D2242A for ; Wed, 4 Nov 2020 00:31:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="ER7zLL0f" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A9E3D2242A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id EEAE66B005C; Tue, 3 Nov 2020 19:31:09 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id E9B866B005D; Tue, 3 Nov 2020 19:31:09 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id D8CA76B0068; Tue, 3 Nov 2020 19:31:09 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0235.hostedemail.com [216.40.44.235]) by kanga.kvack.org (Postfix) with ESMTP id A9ABD6B005C for ; Tue, 3 Nov 2020 19:31:09 -0500 (EST) Received: from smtpin27.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 4513A181AC9BF for ; Wed, 4 Nov 2020 00:31:09 +0000 (UTC) X-FDA: 77444856258.27.tail14_1106c41272bc Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin27.hostedemail.com (Postfix) with ESMTP id 27CF53D66D for ; Wed, 4 Nov 2020 00:31:09 +0000 (UTC) X-HE-Tag: tail14_1106c41272bc X-Filterd-Recvd-Size: 3253 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf21.hostedemail.com (Postfix) with ESMTP for ; Wed, 4 Nov 2020 00:31:08 +0000 (UTC) Received: from X1 (unknown [208.106.6.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 42824223EA; Wed, 4 Nov 2020 00:31:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604449867; bh=PJ+R6XPlsYAvbfPPVfH/b36l9Qxf3mjjxVF2HSd4mPY=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=ER7zLL0fsJywguzjfs3PdQZTmOgVAwtAz5yE5+b1SdacnLAOa3OQtAGteR5rW7qCD Ywc7Z9rUQo9Vi+5FVv3vDhZ6WcR6fNJM16p3Tc2cdLZyMHI3nO70s8Q5UgVBzUwL0U RpnJUxRfACjNdutK4tXoVqBpsWdb3+kUMVEy2qI4= Date: Tue, 3 Nov 2020 16:31:03 -0800 From: Andrew Morton To: Marco Elver Cc: glider@google.com, hpa@zytor.com, paulmck@kernel.org, andreyknvl@google.com, aryabinin@virtuozzo.com, luto@kernel.org, bp@alien8.de, catalin.marinas@arm.com, cl@linux.com, dave.hansen@linux.intel.com, rientjes@google.com, dvyukov@google.com, edumazet@google.com, gregkh@linuxfoundation.org, hdanton@sina.com, mingo@redhat.com, jannh@google.com, Jonathan.Cameron@huawei.com, corbet@lwn.net, iamjoonsoo.kim@lge.com, joern@purestorage.com, keescook@chromium.org, mark.rutland@arm.com, penberg@kernel.org, peterz@infradead.org, sjpark@amazon.com, tglx@linutronix.de, vbabka@suse.cz, will@kernel.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Subject: Re: [PATCH v7 0/9] KFENCE: A low-overhead sampling-based memory safety error detector Message-Id: <20201103163103.109deb9d49a140032d67434f@linux-foundation.org> In-Reply-To: <20201103175841.3495947-1-elver@google.com> References: <20201103175841.3495947-1-elver@google.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, 3 Nov 2020 18:58:32 +0100 Marco Elver wrote: > This adds the Kernel Electric-Fence (KFENCE) infrastructure. KFENCE is a > low-overhead sampling-based memory safety error detector of heap > use-after-free, invalid-free, and out-of-bounds access errors. This > series enables KFENCE for the x86 and arm64 architectures, and adds > KFENCE hooks to the SLAB and SLUB allocators. > > KFENCE is designed to be enabled in production kernels, and has near > zero performance overhead. Compared to KASAN, KFENCE trades performance > for precision. The main motivation behind KFENCE's design, is that with > enough total uptime KFENCE will detect bugs in code paths not typically > exercised by non-production test workloads. One way to quickly achieve a > large enough total uptime is when the tool is deployed across a large > fleet of machines. Has kfence detected any kernel bugs yet? What is its track record? Will a kfence merge permit us to remove some other memory debugging subsystem? We seem to have rather a lot of them.