From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751700AbbCGPVX (ORCPT ); Sat, 7 Mar 2015 10:21:23 -0500 Received: from cantor2.suse.de ([195.135.220.15]:52308 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750820AbbCGPU5 (ORCPT ); Sat, 7 Mar 2015 10:20:57 -0500 From: Mel Gorman To: Dave Chinner Cc: Andrew Morton , Ingo Molnar , Linus Torvalds , Aneesh Kumar , Linux Kernel Mailing List , Linux-MM , xfs@oss.sgi.com, linuxppc-dev@lists.ozlabs.org, Mel Gorman Subject: [PATCH 1/4] mm: thp: Return the correct value for change_huge_pmd Date: Sat, 7 Mar 2015 15:20:48 +0000 Message-Id: <1425741651-29152-2-git-send-email-mgorman@suse.de> X-Mailer: git-send-email 2.1.2 In-Reply-To: <1425741651-29152-1-git-send-email-mgorman@suse.de> References: <1425741651-29152-1-git-send-email-mgorman@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The wrong value is being returned by change_huge_pmd since commit 10c1045f28e8 ("mm: numa: avoid unnecessary TLB flushes when setting NUMA hinting entries") which allows a fallthrough that tries to adjust non-existent PTEs. This patch corrects it. Signed-off-by: Mel Gorman --- mm/huge_memory.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index fc00c8cb5a82..194c0f019774 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1482,6 +1482,7 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, if (__pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { pmd_t entry; + ret = 1; /* * Avoid trapping faults against the zero page. The read-only @@ -1490,11 +1491,10 @@ int change_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, */ if (prot_numa && is_huge_zero_pmd(*pmd)) { spin_unlock(ptl); - return 0; + return ret; } if (!prot_numa || !pmd_protnone(*pmd)) { - ret = 1; entry = pmdp_get_and_clear_notify(mm, addr, pmd); entry = pmd_modify(entry, newprot); ret = HPAGE_PMD_NR; -- 2.1.2