From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-f197.google.com (mail-pf0-f197.google.com [209.85.192.197]) by kanga.kvack.org (Postfix) with ESMTP id 5F59D6B0253 for ; Wed, 1 Feb 2017 01:37:58 -0500 (EST) Received: by mail-pf0-f197.google.com with SMTP id 80so549485508pfy.2 for ; Tue, 31 Jan 2017 22:37:58 -0800 (PST) Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com. [148.163.158.5]) by mx.google.com with ESMTPS id d9si18255598pli.286.2017.01.31.22.37.57 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 31 Jan 2017 22:37:57 -0800 (PST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v116XtwK091141 for ; Wed, 1 Feb 2017 01:37:56 -0500 Received: from e06smtp09.uk.ibm.com (e06smtp09.uk.ibm.com [195.75.94.105]) by mx0b-001b2d01.pphosted.com with ESMTP id 28b22cy21r-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 01 Feb 2017 01:37:56 -0500 Received: from localhost by e06smtp09.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 1 Feb 2017 06:37:54 -0000 Date: Wed, 1 Feb 2017 08:37:48 +0200 From: Mike Rapoport Subject: Re: [PATCH v2 2/5] userfaultfd: non-cooperative: add event for memory unmaps References: <1485542673-24387-1-git-send-email-rppt@linux.vnet.ibm.com> <1485542673-24387-3-git-send-email-rppt@linux.vnet.ibm.com> <20170131163928.4e4e05fbd93358d9b937d79b@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170131163928.4e4e05fbd93358d9b937d79b@linux-foundation.org> Message-Id: <20170201063748.GB7921@rapoport-lnx> Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Andrea Arcangeli , "Dr. David Alan Gilbert" , Hillf Danton , Mike Kravetz , Pavel Emelyanov , Linux-MM , LKML On Tue, Jan 31, 2017 at 04:39:28PM -0800, Andrew Morton wrote: > On Fri, 27 Jan 2017 20:44:30 +0200 Mike Rapoport wrote: > > > When a non-cooperative userfaultfd monitor copies pages in the background, > > it may encounter regions that were already unmapped. Addition of > > UFFD_EVENT_UNMAP allows the uffd monitor to track precisely changes in the > > virtual memory layout. > > > > Since there might be different uffd contexts for the affected VMAs, we > > first should create a temporary representation for the unmap event for each > > uffd context and then notify them one by one to the appropriate userfault > > file descriptors. > > > > The event notification occurs after the mmap_sem has been released. > > I was going to bug you about not updating > Documentation/vm/userfaultfd.txt but the UFFD_FEATURE flags aren't > documented? I'm going to send the documentation update in the next few days. -- Sincerely yours, Mike. -- 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