From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f169.google.com (mail-ig0-f169.google.com [209.85.213.169]) by kanga.kvack.org (Postfix) with ESMTP id 113AA6B0038 for ; Sat, 7 Mar 2015 15:13:28 -0500 (EST) Received: by igbhl2 with SMTP id hl2so12048763igb.5 for ; Sat, 07 Mar 2015 12:13:27 -0800 (PST) Received: from mail-ie0-x231.google.com (mail-ie0-x231.google.com. [2607:f8b0:4001:c03::231]) by mx.google.com with ESMTPS id z12si5132271igu.0.2015.03.07.12.13.27 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sat, 07 Mar 2015 12:13:27 -0800 (PST) Received: by iecat20 with SMTP id at20so40480933iec.6 for ; Sat, 07 Mar 2015 12:13:27 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1425741651-29152-2-git-send-email-mgorman@suse.de> References: <1425741651-29152-1-git-send-email-mgorman@suse.de> <1425741651-29152-2-git-send-email-mgorman@suse.de> Date: Sat, 7 Mar 2015 12:13:27 -0800 Message-ID: Subject: Re: [PATCH 1/4] mm: thp: Return the correct value for change_huge_pmd From: Linus Torvalds Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Dave Chinner , Andrew Morton , Ingo Molnar , Aneesh Kumar , Linux Kernel Mailing List , Linux-MM , xfs@oss.sgi.com, ppc-dev Looks obviously correct. The old code was just very wrong. Acked-by: Linus Torvalds Linus On Sat, Mar 7, 2015 at 7:20 AM, Mel Gorman wrote: > 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 > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org