From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f173.google.com (mail-ig0-f173.google.com [209.85.213.173]) by kanga.kvack.org (Postfix) with ESMTP id F284A6B006E for ; Mon, 9 Mar 2015 16:07:41 -0400 (EDT) Received: by igjz20 with SMTP id z20so24666168igj.4 for ; Mon, 09 Mar 2015 13:07:41 -0700 (PDT) Received: from mail-ie0-x235.google.com (mail-ie0-x235.google.com. [2607:f8b0:4001:c03::235]) by mx.google.com with ESMTPS id n7si13909972icr.25.2015.03.09.13.07.41 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 09 Mar 2015 13:07:41 -0700 (PDT) Received: by iecvy18 with SMTP id vy18so42549965iec.1 for ; Mon, 09 Mar 2015 13:07:41 -0700 (PDT) Date: Mon, 9 Mar 2015 13:07:39 -0700 (PDT) From: David Rientjes Subject: [patch v3] mm, hugetlb: abort __get_user_pages if current has been oom killed In-Reply-To: Message-ID: References: <20150309043051.GA13380@node.dhcp.inet.fi> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Greg Thelen , Naoya Horiguchi , Davidlohr Bueso , "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, linux-mm@kvack.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 potentially deplete 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: Greg Thelen Cc: Naoya Horiguchi Cc: Davidlohr Bueso Acked-by: "Kirill A. Shutemov" Signed-off-by: David Rientjes --- v3: tweak changelog per Greg mm/hugetlb.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -3276,6 +3276,15 @@ long follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, struct page *page; /* + * If we have a pending SIGKILL, don't keep faulting pages and + * potentially allocating memory. + */ + if (unlikely(fatal_signal_pending(current))) { + remainder = 0; + break; + } + + /* * Some archs (sparc64, sh*) have multiple pte_ts to * each hugepage. We have to make sure we get the * first, for the page indexing below to work. -- 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