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=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,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 5A0FBC433DB for ; Tue, 9 Feb 2021 08:20:05 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id A24D864D9E for ; Tue, 9 Feb 2021 08:20:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A24D864D9E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0E7976B0005; Tue, 9 Feb 2021 03:20:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0701D6B006C; Tue, 9 Feb 2021 03:20:03 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E78326B006E; Tue, 9 Feb 2021 03:20:03 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0074.hostedemail.com [216.40.44.74]) by kanga.kvack.org (Postfix) with ESMTP id C9AA66B0005 for ; Tue, 9 Feb 2021 03:20:03 -0500 (EST) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 94A668248076 for ; Tue, 9 Feb 2021 08:20:03 +0000 (UTC) X-FDA: 77798031486.29.fog62_4112a5527605 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 764C9182371A6 for ; Tue, 9 Feb 2021 08:20:03 +0000 (UTC) X-HE-Tag: fog62_4112a5527605 X-Filterd-Recvd-Size: 2468 Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf40.hostedemail.com (Postfix) with ESMTP for ; Tue, 9 Feb 2021 08:20:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=9uWgJ+v5vWmWbn6IhnIBEUxC12yK4PpumRt98hOKJT4=; b=NjRkMhTlaHLW2DlBW0VXVvVqFs s8gsPeTNHsrxlLhJnydn3X3PwN7K88jddVKA40VE9ydzrQb8KKVzNxRZIiGr9J21SEHRz3zIGG+O2 9J+v/kVxeyfqX6S948ui/SsF1wOAYv1SgTdvGv/GKC8qDkaAERAnWdZ3AESrl5eEHqL5ARIMqZDNR FLrpmO4qu8mxq4VsSId5Lx18XIaAMX09mfM1XCv7W0xjT91KQ6LLjRscfJJMIWkix7xZyoUDlaNMs VjmBYmVK7mK6zlwnzh3hbUbpf9YokrCsW0zaP/B9JiWz8n1Cx2uNhhjs6fiw4gyYBT+30SaIpkpkS /cuOJdQA==; Received: from hch by casper.infradead.org with local (Exim 4.94 #2 (Red Hat Linux)) id 1l9OFT-0079an-ER; Tue, 09 Feb 2021 08:19:51 +0000 Date: Tue, 9 Feb 2021 08:19:51 +0000 From: Christoph Hellwig To: Jason Gunthorpe Cc: Peter Xu , dan.j.williams@intel.com, Paolo Bonzini , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-mm@kvack.org, Andrew Morton Subject: Re: [PATCH 0/2] KVM: do not assume PTE is writable after follow_pfn Message-ID: <20210209081951.GA1704636@infradead.org> References: <20210205103259.42866-1-pbonzini@redhat.com> <20210205181411.GB3195@xz-x1> <20210208185133.GW4718@ziepe.ca> <20210208220259.GA71523@xz-x1> <20210208232625.GA4718@ziepe.ca> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210208232625.GA4718@ziepe.ca> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 08, 2021 at 07:26:25PM -0400, Jason Gunthorpe wrote: > > > page_mkclean() has some technique to make the notifier have the right > > > size without becoming entangled in the PTL locks.. > > > > Right. I guess it's because dax doesn't have "struct page*" on the > > back, so it > > It doesn't? I thought DAX cases did? File system DAX has a struct page, device DAX does not. Which means everything using iomap should have a page available, but i'm adding Dan as he should know the details :)