From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762774AbWLKKeu (ORCPT ); Mon, 11 Dec 2006 05:34:50 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762775AbWLKKeu (ORCPT ); Mon, 11 Dec 2006 05:34:50 -0500 Received: from smtp.osdl.org ([65.172.181.25]:39130 "EHLO smtp.osdl.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762774AbWLKKet (ORCPT ); Mon, 11 Dec 2006 05:34:49 -0500 Date: Mon, 11 Dec 2006 02:34:36 -0800 From: Andrew Morton To: Al Viro Cc: Andrew MChuck Ebbert <76306.1226@compuserve.com>, linux-kernel , "Linus Torvalds orton " Subject: Re: [patch] pipe: Don't oops when pipe filesystem isn't mounted Message-Id: <20061211023436.258bb3ea.akpm@osdl.org> In-Reply-To: <20061211102207.GE4587@ftp.linux.org.uk> References: <200612110330_MC3-1-D49B-BC0F@compuserve.com> <20061211005557.04643a75.akpm@osdl.org> <20061211011327.f9478117.akpm@osdl.org> <20061211092130.GB4587@ftp.linux.org.uk> <20061211012545.ed945cbd.akpm@osdl.org> <20061211093314.GC4587@ftp.linux.org.uk> <20061211014727.21c4ab25.akpm@osdl.org> <20061211100301.GD4587@ftp.linux.org.uk> <20061211021718.a6954106.akpm@osdl.org> <20061211102207.GE4587@ftp.linux.org.uk> X-Mailer: Sylpheed version 2.2.7 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 11 Dec 2006 10:22:07 +0000 Al Viro wrote: > On Mon, Dec 11, 2006 at 02:17:18AM -0800, Andrew Morton wrote: > > I think we should aim to have as many subsystems ready to go as possible - > > ideally all of them. Right now we can potentially run userspace before > > AIO, posix-timers, message-queues, BIO, networking, etc are ready to run. > > > > It looks to be pretty easy to fix... > > > > > As for that example, I'd love to see specifics - which driver triggers > > > hotplug? Presumably it happens from an initcall, so we also have something > > > fishy here... > > > > I don't know in this case - but firmware loading from a statically-linked > > driver is a legit thing to do. > > Umm... statically linked driver that might want firmware shouldn't precede > the subsystems unless something is seriously wrong with priorities... There are plenty of drivers in there using subsys_initcall, arch_initcall, postcore_initcall, core_initcall and even one pure_initcall. Heaven knows why. They're drivers :( > IOW, I still wonder what's really going on - pipes are fs_initcall() and > any hardware stuff ought to be simple module_init(). So something fishy > is going on, regardless of anything else. A heck of a lot of things can trigger an /sbin/hotplug run. It could well be that Andrew's driver didn't want to run hotplug at all, but the kernel did it anwyay. But as soon as the script appeared at /sbin/hotplug, and it happened to use foo|bar: boom.