From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754429AbaEHKoy (ORCPT ); Thu, 8 May 2014 06:44:54 -0400 Received: from terminus.zytor.com ([198.137.202.10]:33258 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753488AbaEHKov (ORCPT ); Thu, 8 May 2014 06:44:51 -0400 Date: Thu, 8 May 2014 03:43:19 -0700 From: tip-bot for Rik van Riel Message-ID: Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org, torvalds@linux-foundation.org, kirill.shutemov@linux.intel.com, peterz@infradead.org, hannes@cmpxchg.org, n-horiguchi@ah.jp.nec.com, riel@redhat.com, akpm@linux-foundation.org, mgorman@suse.de, sunil.k.pandey@intel.com, tglx@linutronix.de Reply-To: mingo@kernel.org, hpa@zytor.com, linux-kernel@vger.kernel.org, kirill.shutemov@linux.intel.com, torvalds@linux-foundation.org, peterz@infradead.org, hannes@cmpxchg.org, n-horiguchi@ah.jp.nec.com, riel@redhat.com, akpm@linux-foundation.org, sunil.k.pandey@intel.com, mgorman@suse.de, tglx@linutronix.de In-Reply-To: <20140429153615.2d72098e@annuminas.surriel.com> References: <20140429153615.2d72098e@annuminas.surriel.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:sched/core] mm/numa: Remove BUG_ON() in __handle_mm_fault() Git-Commit-ID: 107437febd495a50e2cd09c81bbaa84d30e57b07 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 107437febd495a50e2cd09c81bbaa84d30e57b07 Gitweb: http://git.kernel.org/tip/107437febd495a50e2cd09c81bbaa84d30e57b07 Author: Rik van Riel AuthorDate: Tue, 29 Apr 2014 15:36:15 -0400 Committer: Ingo Molnar CommitDate: Wed, 7 May 2014 13:33:48 +0200 mm/numa: Remove BUG_ON() in __handle_mm_fault() Changing PTEs and PMDs to pte_numa & pmd_numa is done with the mmap_sem held for reading, which means a pmd can be instantiated and turned into a numa one while __handle_mm_fault() is examining the value of old_pmd. If that happens, __handle_mm_fault() should just return and let the page fault retry, instead of throwing an oops. This is handled by the test for pmd_trans_huge(*pmd) below. Signed-off-by: Rik van Riel Reviewed-by: Naoya Horiguchi Reported-by: Sunil Pandey Signed-off-by: Peter Zijlstra Cc: Andrew Morton Cc: Johannes Weiner Cc: Kirill A. Shutemov Cc: Linus Torvalds Cc: Mel Gorman Cc: linux-mm@kvack.org Cc: lwoodman@redhat.com Cc: dave.hansen@intel.com Link: http://lkml.kernel.org/r/20140429153615.2d72098e@annuminas.surriel.com Signed-off-by: Ingo Molnar --- mm/memory.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/mm/memory.c b/mm/memory.c index d0f0bef..9c2dc65 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3900,9 +3900,6 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, } } - /* THP should already have been handled */ - BUG_ON(pmd_numa(*pmd)); - /* * Use __pte_alloc instead of pte_alloc_map, because we can't * run pte_offset_map on the pmd, if an huge pmd could