From: Andrew Morton Subject: Re: Boot failure with ext2 and initrds Date: Thu, 16 Nov 2006 01:49:20 -0800 Message-ID: <20061116014920.2a0f4d46.akpm@osdl.org> References: <20061114014125.dd315fff.akpm@osdl.org> <20061114184919.GA16020@skynet.ie> <20061114113120.d4c22b02.akpm@osdl.org> <20061115214534.72e6f2e8.akpm@osdl.org> <455C0B6F.7000201@us.ibm.com> <20061115232228.afaf42f2.akpm@osdl.org> <1163666960.4310.40.camel@localhost.localdomain> <20061116011351.1401a00f.akpm@osdl.org> <20061116014809.914a5425.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.osdl.org ([65.172.181.4]:43683 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1422805AbWKPJus (ORCPT ); Thu, 16 Nov 2006 04:50:48 -0500 To: Alex Tomas , cmm@us.ibm.com, Hugh Dickins , Mel Gorman , "Martin J. Bligh" , linux-kernel@vger.kernel.org, "linux-ext4@vger.kernel.org" In-Reply-To: <20061116014809.914a5425.akpm@osdl.org> Sender: linux-ext4-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Thu, 16 Nov 2006 01:48:09 -0800 Andrew Morton wrote: > On Thu, 16 Nov 2006 12:37:17 +0300 > Alex Tomas wrote: > > > >>>>> Andrew Morton (AM) writes: > > > > AM> What lock protects the fields in struct ext[234]_reserve_window from being > > AM> concurrently modified by two CPUs? None, it seems. Ditto > > AM> ext[234]_reserve_window_node. i_mutex will cover it for write(), but not > > AM> for pageout over a file hole. If we end up with a zero- or negative-sized > > AM> window then odd things might happen. > > > > truncate_mutex? > > > > yes. hmm. by which I mean "ext2 doesn't have a truncate_mutex".