From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f182.google.com (mail-wi0-f182.google.com [209.85.212.182]) by kanga.kvack.org (Postfix) with ESMTP id 85B476B006E for ; Thu, 23 Oct 2014 08:39:13 -0400 (EDT) Received: by mail-wi0-f182.google.com with SMTP id bs8so1850345wib.3 for ; Thu, 23 Oct 2014 05:39:13 -0700 (PDT) Received: from kirsi1.inet.fi (mta-out1.inet.fi. [62.71.2.194]) by mx.google.com with ESMTP id cq3si1907842wjb.34.2014.10.23.05.39.11 for ; Thu, 23 Oct 2014 05:39:12 -0700 (PDT) Date: Thu, 23 Oct 2014 15:36:16 +0300 From: "Kirill A. Shutemov" Subject: Re: [RFC][PATCH 3/6] mm: VMA sequence count Message-ID: <20141023123616.GA8809@node.dhcp.inet.fi> References: <20141020215633.717315139@infradead.org> <20141020222841.361741939@infradead.org> <20141022112657.GG30588@node.dhcp.inet.fi> <20141022113951.GB21513@worktop.programming.kicks-ass.net> <20141022115304.GA31486@node.dhcp.inet.fi> <20141022121554.GD21513@worktop.programming.kicks-ass.net> <20141022134416.GA15602@worktop.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20141022134416.GA15602@worktop.programming.kicks-ass.net> Sender: owner-linux-mm@kvack.org List-ID: To: Peter Zijlstra Cc: torvalds@linux-foundation.org, paulmck@linux.vnet.ibm.com, tglx@linutronix.de, akpm@linux-foundation.org, riel@redhat.com, mgorman@suse.de, oleg@redhat.com, mingo@redhat.com, minchan@kernel.org, kamezawa.hiroyu@jp.fujitsu.com, viro@zeniv.linux.org.uk, laijs@cn.fujitsu.com, dave@stgolabs.net, linux-kernel@vger.kernel.org, linux-mm@kvack.org On Wed, Oct 22, 2014 at 03:44:16PM +0200, Peter Zijlstra wrote: > On Wed, Oct 22, 2014 at 02:15:54PM +0200, Peter Zijlstra wrote: > > On Wed, Oct 22, 2014 at 02:53:04PM +0300, Kirill A. Shutemov wrote: > > > Em, no. In this case change_protection() will not touch the pte, since > > > it's pte_none() and the pte_same() check will pass just fine. > > > > Oh, that's what you meant. Yes that's a problem, yes vm_page_prot > > needs wrapping too. > > Maybe also vm_policy, is there anything else that can change while a vma > lives? - vm_flags, obviously; - shared, anon_vma and anon_vma_chain (at least on the first write fault to private mapping); - vm_pgoff (mremap(2) ?); - vm_private_data -- it's all over drivers. Potential nightmare, but seems not in use for anon mappings. -- Kirill A. Shutemov -- 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