From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752685AbbCHXMR (ORCPT ); Sun, 8 Mar 2015 19:12:17 -0400 Received: from mail-ie0-f171.google.com ([209.85.223.171]:45667 "EHLO mail-ie0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439AbbCHXMP (ORCPT ); Sun, 8 Mar 2015 19:12:15 -0400 Date: Sun, 8 Mar 2015 16:12:12 -0700 (PDT) From: David Rientjes X-X-Sender: rientjes@chino.kir.corp.google.com To: Andrew Morton cc: "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [patch] mm, hugetlb: abort __get_user_pages if current has been oom killed Message-ID: User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If __get_user_pages() is faulting a significant number of hugetlb pages, usually as the result of mmap(MAP_LOCKED), it can potentially allocate a very large amount of memory. If the process has been oom killed, this will cause a lot of memory to be overcharged to its memcg since it has access to memory reserves or could potentially deplete all system memory reserves. In the same way that commit 4779280d1ea4 ("mm: make get_user_pages() interruptible") aborted for pending SIGKILLs when faulting non-hugetlb memory, based on the premise of commit 462e00cc7151 ("oom: stop allocating user memory if TIF_MEMDIE is set"), hugetlb page faults now terminate when the process has been oom killed. Cc: "Kirill A. Shutemov" Signed-off-by: David Rientjes --- mm/gup.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/gup.c b/mm/gup.c --- a/mm/gup.c +++ b/mm/gup.c @@ -457,6 +457,8 @@ long __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (!vma || check_vma_flags(vma, gup_flags)) return i ? : -EFAULT; if (is_vm_hugetlb_page(vma)) { + if (unlikely(fatal_signal_pending(current))) + return i ? : -ERESTARTSYS; i = follow_hugetlb_page(mm, vma, pages, vmas, &start, &nr_pages, i, gup_flags);