Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263688AbTETKfi (ORCPT ); Tue, 20 May 2003 06:35:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263686AbTETKfi (ORCPT ); Tue, 20 May 2003 06:35:38 -0400 Received: from boden.synopsys.com ([204.176.20.19]:18631 "HELO boden.synopsys.com") by vger.kernel.org with SMTP id S263681AbTETKfg (ORCPT ); Tue, 20 May 2003 06:35:36 -0400 Date: Tue, 20 May 2003 12:48:20 +0200 From: Alex Riesen To: Carl-Daniel Hailfinger Cc: mikpe@csd.uu.se, sfr@canb.auug.org.au, linux-kernel@vger.kernel.org, linux-laptop@vger.kernel.org Subject: Re: 2.5.69+bk: oops in apmd after waking up from suspend mode Message-ID: <20030520104820.GA7580@Synopsys.COM> Reply-To: alexander.riesen@synopsys.COM References: <200305191216.h4JCGONj015081@harpo.it.uu.se> <20030519123119.GA20385@Synopsys.COM> <20030519144130.GM32559@Synopsys.COM> <3ECA05FA.6090008@gmx.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3ECA05FA.6090008@gmx.net> Organization: Synopsys, Inc. User-Agent: Mutt/1.5.4i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1474 Lines: 35 Carl-Daniel Hailfinger, Tue, May 20, 2003 12:39:54 +0200: > >>>>EIP is at fix_processor_context+0x5f/0x100 > >>>>Process kapmd (pid: 4, threadinfo=c5f0e000 task=c5fbc640) > >>> > >>>After receiving Alex' .config and gcc version (3.2.3), I've been > >>>able to decipher this. current->mm is NULL in the kapmd task. The call > >>> > >>> load_LDT(¤t->mm->context); /* This does lldt */ > >>> > >>>in fix_processor_context() computes the address of context as > >>>(current->mm)+0x7c, which is 0x7c. load_LDT_nolock() dereferences > >>>0x7c+0x14 (void *segments = pc->ldt) and the oops follows. > >>> > >>>As to _why_ kapmd's current->mm is NULL, I don't know. It isn't > >>>when I test APM suspend in 2.5.69-bk. A lot of code dereferences > >>>current->mm without checking, so I guess current->mm==NULL is a bug. > >> > >>i just go and try it with the latest -bk. > > > > no change. Still oopses. > > Could you try to compile with gcc-3.3? In another thread (2.5.69-mm6: > pccard oops) this helped IIRC. I'm suspecting gcc 3.2.3 generates > incorrect code for some cases. I preferably not. Zwane already mentioned that current->mm allowed to be NULL for kernel threads, and i seen it be NULL even before suspending. -alex - 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/