From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261546AbUBUNeO (ORCPT ); Sat, 21 Feb 2004 08:34:14 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261555AbUBUNeO (ORCPT ); Sat, 21 Feb 2004 08:34:14 -0500 Received: from gprs154-206.eurotel.cz ([160.218.154.206]:16512 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S261546AbUBUNeN (ORCPT ); Sat, 21 Feb 2004 08:34:13 -0500 Date: Sat, 21 Feb 2004 14:33:59 +0100 From: Pavel Machek To: Rusty Russell Cc: akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] Booting when CPUs fail to come up. Message-ID: <20040221133359.GA339@elf.ucw.cz> References: <20040220161042.GI23278@elf.ucw.cz> <20040221010811.2D3112C3A8@lists.samba.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20040221010811.2D3112C3A8@lists.samba.org> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi! > > > I recently played with setting a bit in cpu_possible_map that wasn't > > > in cpu_online_map: this can happen without hotplug CPU when a CPU > > > fails to boot, for example. > > > > Is it safe to continue when one cpu is apparently malfunctioning? > > Well, patch was overzealous and no longer required. > > But we shouldn't crash when this happens just because a CPU didn't > come up. I still do not agree. You have a system you tried to kick CPU #13 alive, and something very wrong happened, CPU #13 did not come up. It is there, has full access to memory, it is probably running some kind of program.... I'd not dare mount disks read-write in such situation and I believe crashing early is actually right thing to do. Pavel -- When do you have a heart between your knees? [Johanka's followup: and *two* hearts?]