From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f176.google.com (mail-io0-f176.google.com [209.85.223.176]) by kanga.kvack.org (Postfix) with ESMTP id 74E1A82F65 for ; Mon, 19 Oct 2015 19:18:42 -0400 (EDT) Received: by ioll68 with SMTP id l68so3722902iol.3 for ; Mon, 19 Oct 2015 16:18:42 -0700 (PDT) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id ft2si15894726igb.25.2015.10.19.16.18.41 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Oct 2015 16:18:42 -0700 (PDT) Date: Mon, 19 Oct 2015 16:18:40 -0700 From: Andrew Morton Subject: Re: [PATCH 0/3] hugetlbfs fallocate hole punch race with page faults Message-Id: <20151019161840.63e6afaa73aceec23e351905@linux-foundation.org> In-Reply-To: <1445033310-13155-1-git-send-email-mike.kravetz@oracle.com> References: <1445033310-13155-1-git-send-email-mike.kravetz@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mike Kravetz Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Dave Hansen , Naoya Horiguchi , Hugh Dickins , Davidlohr Bueso On Fri, 16 Oct 2015 15:08:27 -0700 Mike Kravetz wrote: > The hugetlbfs fallocate hole punch code can race with page faults. The > result is that after a hole punch operation, pages may remain within the > hole. No other side effects of this race were observed. > > In preparation for adding userfaultfd support to hugetlbfs, it is desirable > to plug or significantly shrink this hole. This patch set uses the same > mechanism employed in shmem (see commit f00cdc6df7). > "still buggy but not as bad as before" isn't what we strive for ;) What would it take to fix this for real? An exhaustive description of the bug would be a good starting point, thanks. -- 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