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=-0.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 BBD37C433E0 for ; Wed, 20 May 2020 00:10:01 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7DA5F20825 for ; Wed, 20 May 2020 00:10:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="T4knsEdc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7DA5F20825 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 1C81780034; Tue, 19 May 2020 20:10:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1787C8002C; Tue, 19 May 2020 20:10:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 08E3680034; Tue, 19 May 2020 20:10:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0037.hostedemail.com [216.40.44.37]) by kanga.kvack.org (Postfix) with ESMTP id E62768002C for ; Tue, 19 May 2020 20:10:00 -0400 (EDT) Received: from smtpin11.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 99203181AEF10 for ; Wed, 20 May 2020 00:10:00 +0000 (UTC) X-FDA: 76835164560.11.care70_3a411ce90f831 X-HE-Tag: care70_3a411ce90f831 X-Filterd-Recvd-Size: 2624 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf23.hostedemail.com (Postfix) with ESMTP for ; Wed, 20 May 2020 00:10:00 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 127CA207C4; Wed, 20 May 2020 00:09:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1589933399; bh=ncS4/WJ13FIx6+ovp8byd0aXq8LXhHwOMR/bGy+ucpM=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=T4knsEdcbJxOWgUV5tpYiL5MmKlO+Lup+tlcl6W5gxC7ZR1kNeChYC+sK2ciY9bbJ IDXkgQPZWuoHtFdmT06VI2UA+8pxn/h8x/CujDcnmo0Tc385EL3r++J5E26Jx/Q3hS C2mYP3dD9X2uXhyuPW5VrKIi7I2qNpiXTTvD8HOU= Date: Tue, 19 May 2020 17:09:58 -0700 From: Andrew Morton To: Andrey Konovalov Cc: Marco Elver , Dmitry Vyukov , Alexander Potapenko , LKML , kasan-dev , Andrey Ryabinin , Linux Memory Management List , kernel test robot Subject: Re: [PATCH] kasan: Disable branch tracing for core runtime Message-Id: <20200519170958.d6e399f7f98286c1162f1383@linux-foundation.org> In-Reply-To: References: <20200519182459.87166-1-elver@google.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; 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, 19 May 2020 23:05:46 +0200 Andrey Konovalov wrote: > On Tue, May 19, 2020 at 8:25 PM Marco Elver wrote: > > > > During early boot, while KASAN is not yet initialized, it is possible to > > enter reporting code-path and end up in kasan_report(). While > > uninitialized, the branch there prevents generating any reports, > > however, under certain circumstances when branches are being traced > > (TRACE_BRANCH_PROFILING), we may recurse deep enough to cause kernel > > reboots without warning. > > > > To prevent similar issues in future, we should disable branch tracing > > for the core runtime. > > > > ... > > Reviewed-by: Andrey Konovalov Thanks, I queued this for 5.7.