From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f71.google.com (mail-wr1-f71.google.com [209.85.221.71]) by kanga.kvack.org (Postfix) with ESMTP id EABD36B0006 for ; Fri, 12 Oct 2018 03:24:36 -0400 (EDT) Received: by mail-wr1-f71.google.com with SMTP id t17-v6so7157469wrv.13 for ; Fri, 12 Oct 2018 00:24:36 -0700 (PDT) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id l4-v6sor221781wru.48.2018.10.12.00.24.35 for (Google Transport Security); Fri, 12 Oct 2018 00:24:35 -0700 (PDT) Subject: Re: [PATCH] mm: Speed up mremap on large regions References: <20181009201400.168705-1-joel@joelfernandes.org> From: Paolo Bonzini Message-ID: <927d98c0-ec81-ce7a-994d-6405abce18db@redhat.com> Date: Fri, 12 Oct 2018 09:24:32 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Jann Horn , joel@joelfernandes.org Cc: kernel list , Linux-MM , kernel-team@android.com, Minchan Kim , Hugh Dickins , lokeshgidra@google.com, Andrew Morton , Greg Kroah-Hartman , Kate Stewart , pombredanne@nexb.com, Thomas Gleixner , Boris Ostrovsky , Juergen Gross , =?UTF-8?B?UmFkaW0gS3LEjW3DocWZ?= , kvm@vger.kernel.org On 12/10/2018 05:21, Jann Horn wrote: > I don't know how this interacts with shadow paging implementations. Shadow paging simply uses MMU notifiers and that does not assume that PTE invalidation is atomic. The invalidate_range_start and invalidate_range_end calls are not affected by Joel's patch, so it's ok for KVM and also for other users of MMU notifiers. Paolo