From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753254AbbCPIgr (ORCPT ); Mon, 16 Mar 2015 04:36:47 -0400 Received: from e06smtp14.uk.ibm.com ([195.75.94.110]:39694 "EHLO e06smtp14.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751475AbbCPIgo (ORCPT ); Mon, 16 Mar 2015 04:36:44 -0400 From: Christian Borntraeger To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Christian Borntraeger Subject: [PATCH] mm: trigger panic on bad page or PTE states if panic_on_oops Date: Mon, 16 Mar 2015 09:37:01 +0100 Message-Id: <1426495021-6408-1-git-send-email-borntraeger@de.ibm.com> X-Mailer: git-send-email 2.3.0 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 15031608-0017-0000-0000-000003613729 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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. Signed-off-by: Christian Borntraeger --- mm/memory.c | 2 ++ mm/page_alloc.c | 2 ++ 2 files changed, 4 insertions(+) diff --git a/mm/memory.c b/mm/memory.c index 2c3536c..bdbf9cc 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -696,6 +696,8 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, printk(KERN_ALERT "vma->vm_file->f_op->mmap: %pSR\n", vma->vm_file->f_op->mmap); dump_stack(); + if (panic_on_oops) + panic("Fatal exception"); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); } diff --git a/mm/page_alloc.c b/mm/page_alloc.c index 8e20f9c..8c19db3 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -337,6 +337,8 @@ static void bad_page(struct page *page, const char *reason, print_modules(); dump_stack(); + if (panic_on_oops) + panic("Fatal exception"); out: /* Leave bad fields for debug, except PageBuddy could make trouble */ page_mapcount_reset(page); /* remove PageBuddy */ -- 2.3.0