From owner-freebsd-hackers@FreeBSD.ORG Thu May 7 11:31:22 2015 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 3A1FDACE for ; Thu, 7 May 2015 11:31:22 +0000 (UTC) Received: from puchar.net (puchar.net [188.252.31.250]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "puchar.net", Issuer "puchar.net" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id B716B174A for ; Thu, 7 May 2015 11:31:21 +0000 (UTC) Received: Received: from 127.0.0.1 (localhost [127.0.0.1]) by puchar.net (8.14.9/8.14.9) with ESMTP id t47BLJZa090437 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Thu, 7 May 2015 13:21:19 +0200 (CEST) (envelope-from wojtek@puchar.net) Received: from laptop.wojtek.intra (localhost [127.0.0.1]) by laptop.wojtek.intra (8.14.9/8.14.9) with ESMTP id t47BLFYV000874; Thu, 7 May 2015 13:21:15 +0200 (CEST) (envelope-from wojtek@puchar.net) Received: from localhost (wojtek@localhost) by laptop.wojtek.intra (8.14.9/8.14.9/Submit) with ESMTP id t47BL9IX000871; Thu, 7 May 2015 13:21:10 +0200 (CEST) (envelope-from wojtek@puchar.net) X-Authentication-Warning: laptop.wojtek.intra: wojtek owned process doing -bs Date: Thu, 7 May 2015 13:21:09 +0200 (CEST) From: Wojciech Puchar X-X-Sender: wojtek@laptop.wojtek.intra To: "Julian H. Stacey" cc: NGie Cooper , "freebsd-hackers@freebsd.org" , Ryan Stone Subject: Re: What's required to make removal of a mounted USB stick safe? In-Reply-To: <201505062159.t46Lx0iZ028607@fire.js.berklix.net> Message-ID: References: <201505062159.t46Lx0iZ028607@fire.js.berklix.net> User-Agent: Alpine 2.20 (BSF 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.4.3 (puchar.net [10.0.1.1]); Thu, 07 May 2015 13:21:20 +0200 (CEST) X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 07 May 2015 11:31:22 -0000 > - Deep kernel work (dont hold your breath, see 30 above, & don't look at me :-) > - Cobble up some C to run from user space, not as root, > so that your UFS is not mounted, but accessed by user level > programs (much like mwrite & mread for accessing DOS media of old) > - man 8 amd : set a short timeout to auto unmount, > it wont total solve your problem, but should lessen the frequency of panics. > - Mount the USB media on a spare laptop running as an NFS+ AMD server, > then access the FS via NFS from your real client big PC. When > you pull the stick by accident forgetting its mounted, just the > laptop crashes afte a bit, the AMD access on the other PC just > hangs but doesnt crash. > - Encourage A SOC (google summer of code) student to look at it, > probably wont come to a solution though, see 30 above. > - Toss money at the problem :-) If your company can afford some cash, either: > - help fund FreeBSD Foundation & ask them to solve it, > - Or pay some consultant somewhere to look at it, Here's a globaly > geographicaly indexed list http://berklix.com/consultants/ > maybe there's one near your company ? - mount using fuse