From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=Fj1U=YL=kvack.org=owner-linux-mm@kernel.org>
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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS,
	MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B3640CA9EA0
	for <linux-mm@archiver.kernel.org>; Fri, 18 Oct 2019 15:27:15 +0000 (UTC)
Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17])
	by mail.kernel.org (Postfix) with ESMTP id 87C6420700
	for <linux-mm@archiver.kernel.org>; Fri, 18 Oct 2019 15:27:15 +0000 (UTC)
DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 87C6420700
Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de
Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org
Received: by kanga.kvack.org (Postfix)
	id 04DA48E0005; Fri, 18 Oct 2019 11:27:15 -0400 (EDT)
Received: by kanga.kvack.org (Postfix, from userid 40)
	id F19558E0003; Fri, 18 Oct 2019 11:27:14 -0400 (EDT)
X-Delivered-To: int-list-linux-mm@kvack.org
Received: by kanga.kvack.org (Postfix, from userid 63042)
	id E07748E0005; Fri, 18 Oct 2019 11:27:14 -0400 (EDT)
X-Delivered-To: linux-mm@kvack.org
Received: from forelay.hostedemail.com (smtprelay0006.hostedemail.com [216.40.44.6])
	by kanga.kvack.org (Postfix) with ESMTP id BA3AF8E0003
	for <linux-mm@kvack.org>; Fri, 18 Oct 2019 11:27:14 -0400 (EDT)
Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251])
	by forelay02.hostedemail.com (Postfix) with SMTP id 29F6D6D8B
	for <linux-mm@kvack.org>; Fri, 18 Oct 2019 15:27:14 +0000 (UTC)
X-FDA: 76057283988.10.act53_3f1eadbb9d433
X-HE-Tag: act53_3f1eadbb9d433
X-Filterd-Recvd-Size: 1842
Received: from verein.lst.de (verein.lst.de [213.95.11.211])
	by imf36.hostedemail.com (Postfix) with ESMTP
	for <linux-mm@kvack.org>; Fri, 18 Oct 2019 15:27:13 +0000 (UTC)
Received: by verein.lst.de (Postfix, from userid 2407)
	id 1D1AF68AFE; Fri, 18 Oct 2019 17:27:10 +0200 (CEST)
Date: Fri, 18 Oct 2019 17:27:09 +0200
From: Christoph Hellwig <hch@lst.de>
To: glider@google.com
Cc: Andrew Morton <akpm@linux-foundation.org>, Jens Axboe <axboe@kernel.dk>,
	Theodore Ts'o <tytso@mit.edu>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	"Martin K . Petersen" <martin.petersen@oracle.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Christoph Hellwig <hch@lst.de>, Eric Dumazet <edumazet@google.com>,
	Eric Van Hensbergen <ericvh@gmail.com>,
	Takashi Iwai <tiwai@suse.com>,
	Vegard Nossum <vegard.nossum@oracle.com>,
	Dmitry Vyukov <dvyukov@google.com>, linux-mm@kvack.org
Subject: Re: [PATCH RFC v1 23/26] kmsan: unpoisoning buffers from devices
 etc.
Message-ID: <20191018152709.GB32281@lst.de>
References: <20191018094304.37056-1-glider@google.com> <20191018094304.37056-24-glider@google.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20191018094304.37056-24-glider@google.com>
User-Agent: Mutt/1.5.17 (2007-11-01)
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: <linux-mm.kvack.org>

On Fri, Oct 18, 2019 at 11:43:01AM +0200, glider@google.com wrote:
> When data is copied to memory from a device KMSAN should treat it as
> initialized. In most cases it's enough to just unpoison the buffer that
> is known to come from a device.
> In the case with __do_page_cache_readahead() and bio_copy_user_iov() we
> have to mark the whole pages as ignored by KMSAN, as it's not obvious
> where these pages are read again.

I'm not sure how your annotations work because you only Cced me on this
one patch.  Don't do that.