From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752879Ab3BOW4v (ORCPT ); Fri, 15 Feb 2013 17:56:51 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:49364 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752735Ab3BOW4q (ORCPT ); Fri, 15 Feb 2013 17:56:46 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gerald Schaefer , Vivek Goyal , Andrea Arcangeli , Hugh Dickins , Martin Schwidefsky , Heiko Carstens , Andrew Morton , Linus Torvalds Subject: [ 03/10] mm: dont overwrite mm->def_flags in do_mlockall() Date: Fri, 15 Feb 2013 14:56:35 -0800 Message-Id: <20130215225543.945674212@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130215225543.586012193@linuxfoundation.org> References: <20130215225543.586012193@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.7-stable review patch. If anyone has any objections, please let me know. ------------------ From: Gerald Schaefer commit 9977f0f164d46613288e0b5778eae500dfe06f31 upstream. With commit 8e72033f2a48 ("thp: make MADV_HUGEPAGE check for mm->def_flags") the VM_NOHUGEPAGE flag may be set on s390 in mm->def_flags for certain processes, to prevent future thp mappings. This would be overwritten by do_mlockall(), which sets it back to 0 with an optional VM_LOCKED flag set. To fix this, instead of overwriting mm->def_flags in do_mlockall(), only the VM_LOCKED flag should be set or cleared. Signed-off-by: Gerald Schaefer Reported-by: Vivek Goyal Cc: Andrea Arcangeli Cc: Hugh Dickins Cc: Martin Schwidefsky Cc: Heiko Carstens Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/mlock.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/mm/mlock.c +++ b/mm/mlock.c @@ -517,11 +517,11 @@ SYSCALL_DEFINE2(munlock, unsigned long, static int do_mlockall(int flags) { struct vm_area_struct * vma, * prev = NULL; - unsigned int def_flags = 0; if (flags & MCL_FUTURE) - def_flags = VM_LOCKED; - current->mm->def_flags = def_flags; + current->mm->def_flags |= VM_LOCKED; + else + current->mm->def_flags &= ~VM_LOCKED; if (flags == MCL_FUTURE) goto out;