From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750755AbWAYHPg (ORCPT ); Wed, 25 Jan 2006 02:15:36 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750759AbWAYHPg (ORCPT ); Wed, 25 Jan 2006 02:15:36 -0500 Received: from smtp.osdl.org ([65.172.181.4]:49866 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S1750755AbWAYHPf (ORCPT ); Wed, 25 Jan 2006 02:15:35 -0500 Date: Tue, 24 Jan 2006 23:15:10 -0800 From: Andrew Morton To: Fernando Luis Vazquez Cao Cc: ebiederm@xmission.com, ak@suse.de, vgoyal@in.ibm.com, linux-kernel@vger.kernel.org, fastboot@lists.osdl.org Subject: Re: [PATCH 3/5] stack overflow safe kdump (2.6.16-rc1-i386) - fault Message-Id: <20060124231510.35eabe15.akpm@osdl.org> In-Reply-To: <1138172000.2370.68.camel@localhost.localdomain> References: <1138172000.2370.68.camel@localhost.localdomain> X-Mailer: Sylpheed version 1.0.4 (GTK+ 1.2.10; i386-redhat-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 Fernando Luis Vazquez Cao wrote: > > When we have a bloated stack it is likely that it ends up making an > invalid memory access that in turn causes a page fault. Take this case > into account in the page fault code. > > + if (!virt_addr_valid(tsk)) { Is virt_addr_valid() a sufficiently strong test here? One could probe the address to see if it generates a fault, like the __get_user() in kmem_cache_create(). > + printk("do_page_fault: Discarding invalid 'current' struct task_struct * = 0x%p\n", tsk); > + printk("do_page_fault: Discarding invalid current->mm struct mm_struct * = 0x%p\n", mm); Try to make the code look nice in an 80-col window please.