From owner-freebsd-stable@freebsd.org Tue Mar 14 23:47:20 2017 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 5BCF7D0DBC7; Tue, 14 Mar 2017 23:47:20 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from raven.bwct.de (raven.bwct.de [195.149.99.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "raven.bwct.de", Issuer "raven.bwct.de" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id E5DC81CE9; Tue, 14 Mar 2017 23:47:19 +0000 (UTC) (envelope-from ticso@cicely7.cicely.de) Received: from mail.cicely.de ([10.1.1.37]) by raven.bwct.de (8.15.2/8.15.2) with ESMTPS id v2ENihnU040775 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Wed, 15 Mar 2017 00:44:43 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (cicely7.cicely.de [10.1.1.9]) by mail.cicely.de (8.14.5/8.14.4) with ESMTP id v2ENifKN051896 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 15 Mar 2017 00:44:41 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: from cicely7.cicely.de (localhost [127.0.0.1]) by cicely7.cicely.de (8.15.2/8.15.2) with ESMTP id v2ENiecG025847; Wed, 15 Mar 2017 00:44:40 +0100 (CET) (envelope-from ticso@cicely7.cicely.de) Received: (from ticso@localhost) by cicely7.cicely.de (8.15.2/8.15.2/Submit) id v2ENicbl025846; Wed, 15 Mar 2017 00:44:38 +0100 (CET) (envelope-from ticso) Date: Wed, 15 Mar 2017 00:44:38 +0100 From: Bernd Walter To: Mark Millard Cc: Andrew Turner , freebsd-arm , FreeBSD Current , FreeBSD-STABLE Mailing List Subject: Re: arm64 fork/swap data corruptions: A ~110 line C program demonstrating an example (Pine64+ 2GB context) [Corrected subject: arm64!] Message-ID: <20170314234437.GA25820@cicely7.cicely.de> Reply-To: ticso@cicely.de References: <01735A68-FED6-4E63-964F-0820FE5C446C@dsl-only.net> <16B3D614-62E1-4E58-B409-8DB9DBB35BCB@dsl-only.net> <5BEAFC6C-DA80-4D7B-AB55-977E585D1ACC@dsl-only.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Operating-System: FreeBSD cicely7.cicely.de 10.2-RELEASE amd64 User-Agent: Mutt/1.5.11 X-Spam-Status: No, score=-4.4 required=5.0 tests=ALL_TRUSTED=-1, BAYES_00=-1.9, RP_MATCHES_RCVD=-1.507 autolearn=ham version=3.3.0 X-Spam-Checker-Version: SpamAssassin 3.3.0 (2010-01-18) on spamd.cicely.de X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 14 Mar 2017 23:47:20 -0000 On Tue, Mar 14, 2017 at 03:28:53PM -0700, Mark Millard wrote: > [test_check() between the fork and the wait/sleep prevents the > failure from occurring. Even a small access to the memory at > that stage prevents the failure. Details follow.] Maybe a stupid question, since you might have written it somewhere. What medium do you swap to? I've seen broken firmware on microSD cards doing silent data corruption for some access patterns. -- B.Walter http://www.bwct.de Modbus/TCP Ethernet I/O Baugruppen, ARM basierte FreeBSD Rechner uvm.