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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F471C433FE for ; Wed, 23 Mar 2022 16:48:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 9AE536B0072; Wed, 23 Mar 2022 12:48:45 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 95D0E6B0074; Wed, 23 Mar 2022 12:48:45 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 825BD6B0075; Wed, 23 Mar 2022 12:48:45 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0109.hostedemail.com [216.40.44.109]) by kanga.kvack.org (Postfix) with ESMTP id 734566B0072 for ; Wed, 23 Mar 2022 12:48:45 -0400 (EDT) Received: from smtpin18.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 2E96C9879D for ; Wed, 23 Mar 2022 16:48:45 +0000 (UTC) X-FDA: 79276235010.18.0A6858D Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf02.hostedemail.com (Postfix) with ESMTP id 9AA218001F for ; Wed, 23 Mar 2022 16:48:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=W+s1QtlhSjsq/MYdWCk5+G4u/fvPQ1sjexrZPDlle7U=; b=NVmfU9gN6D2xiHnQorCyLErlMs U75m/ZIPXG+GbT5eleEf1PGKH8jyEgCt7hHt6Kj6DDP5mPL4JdRCHzDp4q3WnPUE42lRQwx8wUve8 Nc1cqhvX2QMSUAStiGtWIwtscERy7uYA3aWpSMUPG5u2JU6+XIwI9Cn4XMdYRuAcfPRwmHpsNedJj curK+g8VFcoyQi9NnGPBVLuVswoA2p83HqPwDxz7drPWsJb0V0h+YpD1dOS/Avce/hdHq4Nd4EmBb xIFn2kIMDbXUs5oJLcv75XN0lGed7jWLzH4dACczYTEXegoxA7br19xj1b2W+1INkSWlTlK5VpOgt 1pUlS8hQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nX4A5-00EIc6-EX; Wed, 23 Mar 2022 16:48:41 +0000 Date: Wed, 23 Mar 2022 09:48:41 -0700 From: Christoph Hellwig To: David Hildenbrand Cc: Xiaoguang Wang , linux-mm@kvack.org, target-devel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-block@vger.kernel.org, xuyu@linux.alibaba.com, bostroesser@gmail.com Subject: Re: [RFC 2/3] mm: export zap_page_range() Message-ID: References: <20220318095531.15479-1-xiaoguang.wang@linux.alibaba.com> <20220318095531.15479-3-xiaoguang.wang@linux.alibaba.com> <37d6b269-dd9d-dbd1-74b1-4191cc3d4bf9@linux.alibaba.com> <019a2159-57d6-c330-53c5-38458b6b5ec9@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <019a2159-57d6-c330-53c5-38458b6b5ec9@redhat.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Stat-Signature: gpebz961nr6sx6g1u1injpk3mrbo6a4k Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=NVmfU9gN; spf=none (imf02.hostedemail.com: domain of BATV+e62b50da79483f2da7a7+6786+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+e62b50da79483f2da7a7+6786+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: 9AA218001F X-HE-Tag: 1648054124-243923 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 Tue, Mar 22, 2022 at 02:08:13PM +0100, David Hildenbrand wrote: > Reason is that we don't want anybody to blindly zap_page_range() within > random VMAs from a kernel module. Not just that, but there is no business for modules doing this at all. These kinds of VM hooks for random drivers are not a good idea.