From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 933AAC38A2A for ; Thu, 7 May 2020 21:47:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CB2120870 for ; Thu, 7 May 2020 21:47:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="XVrhA0AL" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727787AbgEGVrv (ORCPT ); Thu, 7 May 2020 17:47:51 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:35155 "EHLO us-smtp-delivery-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726480AbgEGVrv (ORCPT ); Thu, 7 May 2020 17:47:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1588888070; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=V5idkJrYxhm5CKR6p7Gbs2X4uJl1eZjYfow+72g1gg4=; b=XVrhA0ALlpy/yMAnnpT/QFcqbFP3QwHejk3D4ONU1ABAoc3F6nnTBwqPo1sx8kdGtmdrtU 6xyZ1yZLdOeA8/lQLF5fIkivGIVFi5i2Csvwd9nQjYua9B+K3cdigJbq+U/FWYQHzLyrGO 0sTlC/ZUcqO9+p0yPV1RlICBargEP+0= Received: from mail-qt1-f200.google.com (mail-qt1-f200.google.com [209.85.160.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-118-Ia2e86xtMJCrar6YxxQUNw-1; Thu, 07 May 2020 17:47:48 -0400 X-MC-Unique: Ia2e86xtMJCrar6YxxQUNw-1 Received: by mail-qt1-f200.google.com with SMTP id x56so8754400qtc.10 for ; Thu, 07 May 2020 14:47:48 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=V5idkJrYxhm5CKR6p7Gbs2X4uJl1eZjYfow+72g1gg4=; b=aoAmlUjeJpjmHeJybfmFxVGtKvuztUhcEYBMoPECaVQZPr8E0b58v6M7vg/rdYWhYr wt65IRtMcZ6m9tEWNwK2kKNrvK+jZ1Gd0+2fUiW99KA4TM2IpI+Ja+klc5w6FUHVlzjL mQcSXHfaKMBrG/efBLw2UYuoQBMYkHLH7IMoIa2kbju+tbG2TbbN8sWtPNiaH6m0xpMx uWxEpvC+nqcj/6mdvWro61BmUl88EjNV74TFwuR/5heV+A5MaE1auN7Vif3euBl4icES 9KbXg6s0PMQY3bmHhJuD7W8vuHXgUgbqZemi9ZDq+uKHF0WEQfqiTgAFFsrL+f6a5mPY ZHIg== X-Gm-Message-State: AGi0PuZR53q6MZGAZIopl8SqgvOePeEFjes+lUEF6g2wpw3sNFU3yayT I49i8CTpopnkwJAyOthcXAzWiyApzFtmMoedc4I384xiiq9pwiura1WlhbsotnwHCo0EcjY9ATY v1Bp1gm5clsPdBBpDb0yDkq5W X-Received: by 2002:ac8:6f52:: with SMTP id n18mr1046852qtv.239.1588888067431; Thu, 07 May 2020 14:47:47 -0700 (PDT) X-Google-Smtp-Source: APiQypKU8dHnF+0R9W7NWKvWqdYptCothy11u6hec6e2fkEn81AVH/NON7Vco4MKd/Vk4uGjBvtn/Q== X-Received: by 2002:ac8:6f52:: with SMTP id n18mr1046826qtv.239.1588888066982; Thu, 07 May 2020 14:47:46 -0700 (PDT) Received: from xz-x1 ([2607:9880:19c0:32::2]) by smtp.gmail.com with ESMTPSA id t67sm5214265qka.17.2020.05.07.14.47.45 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 07 May 2020 14:47:45 -0700 (PDT) Date: Thu, 7 May 2020 17:47:44 -0400 From: Peter Xu To: Alex Williamson Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, cohuck@redhat.com, jgg@ziepe.ca Subject: Re: [PATCH v2 2/3] vfio-pci: Fault mmaps to enable vma tracking Message-ID: <20200507214744.GP228260@xz-x1> References: <158871401328.15589.17598154478222071285.stgit@gimli.home> <158871569380.15589.16950418949340311053.stgit@gimli.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <158871569380.15589.16950418949340311053.stgit@gimli.home> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Alex, On Tue, May 05, 2020 at 03:54:53PM -0600, Alex Williamson wrote: > +/* > + * Zap mmaps on open so that we can fault them in on access and therefore > + * our vma_list only tracks mappings accessed since last zap. > + */ > +static void vfio_pci_mmap_open(struct vm_area_struct *vma) > +{ > + zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start); A pure question: is this only a safety-belt or it is required in some known scenarios? In all cases: Reviewed-by: Peter Xu Thanks, -- Peter Xu