From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752483AbbCPLNB (ORCPT ); Mon, 16 Mar 2015 07:13:01 -0400 Received: from e06smtp14.uk.ibm.com ([195.75.94.110]:44245 "EHLO e06smtp14.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750899AbbCPLNA (ORCPT ); Mon, 16 Mar 2015 07:13:00 -0400 Message-ID: <5506BAB6.3080104@de.ibm.com> Date: Mon, 16 Mar 2015 12:12:54 +0100 From: Christian Borntraeger User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: "Kirill A. Shutemov" CC: linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] mm: trigger panic on bad page or PTE states if panic_on_oops References: <1426495021-6408-1-git-send-email-borntraeger@de.ibm.com> <20150316110033.GA20546@node.dhcp.inet.fi> In-Reply-To: <20150316110033.GA20546@node.dhcp.inet.fi> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15031611-0017-0000-0000-00000361EF0E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Am 16.03.2015 um 12:00 schrieb Kirill A. Shutemov: > On Mon, Mar 16, 2015 at 09:37:01AM +0100, Christian Borntraeger wrote: >> while debugging a memory management problem it helped a lot to >> get a system dump as early as possible for bad page states. >> >> Lets assume that if panic_on_oops is set then the system should >> not continue with broken mm data structures. > > bed_pte is not an oops. I know that this is not an oops, but semantically it is like one. I certainly want to a way to hard stop the system if something like that happens. Would something like panic_on_mm_error be better? > > Probably we should consider putting VM_BUG() at the end of these > functions instead. That is probably also a workable solution if I can reproduce the issue on my system, but VM_BUG defaults to off for many production systems (RHEL, SLES..) Any other suggestion? Christian