Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261920AbVASWIU (ORCPT ); Wed, 19 Jan 2005 17:08:20 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261931AbVASWHs (ORCPT ); Wed, 19 Jan 2005 17:07:48 -0500 Received: from alog0085.analogic.com ([208.224.220.100]:13440 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S261925AbVASWBm (ORCPT ); Wed, 19 Jan 2005 17:01:42 -0500 Date: Wed, 19 Jan 2005 17:01:23 -0500 (EST) From: linux-os Reply-To: linux-os@analogic.com To: Andrew Morton cc: Badari Pulavarty , linux-kernel@vger.kernel.org Subject: Re: 2.6.10-mm1 hang In-Reply-To: <20050119133136.7a1c0454.akpm@osdl.org> Message-ID: References: <1106153215.3577.134.camel@dyn318077bld.beaverton.ibm.com> <20050119133136.7a1c0454.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1543 Lines: 45 On Wed, 19 Jan 2005, Andrew Morton wrote: > Badari Pulavarty wrote: >> >> I was playing with kexec+kdump and ran into this on 2.6.10-mm1. >> I have seen similar behaviour on 2.6.10. >> >> I am using a 4-way P-III machine. I have a module which tries >> gets same spinlock twice. When I try to "insmod" this module, >> my system hangs. All my windows froze, no more new logins, >> console froze, doesn't respond to sysrq. I wasn't expecting >> a system hang. Why ? Ideas ? >> > > Maybe all the other CPUs are stuck trying to send an IPI to this one? An > NMI watchdog trace would tell. > >> #include >> #include >> #include >> spinlock_t mylock = SPIN_LOCK_UNLOCKED; >> static int __init panic_init(void) >> { >> spin_lock_irq(&mylock); >> spin_lock_irq(&mylock); >> return 1; >> } > - What would you expect this to do? After the first lock is obtained, the second MUST fail forever or else the spin-lock doesn't work. The code, above, just proves that spin-locks work! Cheers, Dick Johnson Penguin : Linux version 2.6.10 on an i686 machine (5537.79 BogoMips). Notice : All mail here is now cached for review by Dictator Bush. 98.36% of all statistics are fiction. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/