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 496BEC433F5 for ; Wed, 13 Apr 2022 09:15:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ABA1C6B0072; Wed, 13 Apr 2022 05:15:53 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A6A276B0073; Wed, 13 Apr 2022 05:15:53 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 931F16B0074; Wed, 13 Apr 2022 05:15:53 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (relay.hostedemail.com [64.99.140.26]) by kanga.kvack.org (Postfix) with ESMTP id 83A6E6B0072 for ; Wed, 13 Apr 2022 05:15:53 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id 45EE320657 for ; Wed, 13 Apr 2022 09:15:53 +0000 (UTC) X-FDA: 79351298586.04.1AF197B Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf31.hostedemail.com (Postfix) with ESMTP id 5FFCF20003 for ; Wed, 13 Apr 2022 09:15:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649841352; x=1681377352; h=date:from:to:cc:subject:message-id:reply-to:references: mime-version:in-reply-to; bh=Qyg9qkfEOmRnd7ecWKODTY6fNCX00KNJAm/6F+S5OvQ=; b=K0CiSFGkYoteOrumziEKiudfywM5ETox3ats6kN5ugWV9LeU9zXeLOnp fW3yrJOgkT/5FlE/eek8xyrQvax6JpGjgNPAEpIKSBaf5oNMNeeo+Mz7r EAlg05rwQnfXz4oMILVZaNm8D9TCRxSna6Tw/OT+HG7t42foPOK4J96us e/B0Ih73ElvmSZY8kqFYH5fISf27ii1+99JQpfi7EAiixYxNEHvnpqNOS mX0lwkhPe5canZ13gJ1qkHuEFiCR1jJS6xB/+lr/bPWDtY0oVl4ug/D+e BLM6mbs4EbIe0yGTtyQPCjjTJoGOJfIu5/S2nxvfbruxpTuGVmZX2u879 g==; X-IronPort-AV: E=McAfee;i="6400,9594,10315"; a="261464213" X-IronPort-AV: E=Sophos;i="5.90,256,1643702400"; d="scan'208";a="261464213" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2022 02:15:51 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,256,1643702400"; d="scan'208";a="700175232" Received: from chaop.bj.intel.com (HELO localhost) ([10.240.192.101]) by fmsmga001.fm.intel.com with ESMTP; 13 Apr 2022 02:15:43 -0700 Date: Wed, 13 Apr 2022 17:15:33 +0800 From: Chao Peng To: "Kirill A. Shutemov" Cc: Sean Christopherson , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, qemu-devel@nongnu.org, Paolo Bonzini , Jonathan Corbet , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Vishal Annapurve , Yu Zhang , "Kirill A . Shutemov" , luto@kernel.org, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com Subject: Re: [PATCH v5 04/13] mm/shmem: Restrict MFD_INACCESSIBLE memory against RLIMIT_MEMLOCK Message-ID: <20220413091533.GC10041@chaop.bj.intel.com> Reply-To: Chao Peng References: <20220310140911.50924-1-chao.p.peng@linux.intel.com> <20220310140911.50924-5-chao.p.peng@linux.intel.com> <20220411153233.54ljmi7zgqovhgsn@box.shutemov.name> <20220412133925.GG8013@chaop.bj.intel.com> <20220412192821.xliop57sblvjx4t4@box.shutemov.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220412192821.xliop57sblvjx4t4@box.shutemov.name> User-Agent: Mutt/1.9.4 (2018-02-28) Authentication-Results: imf31.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=K0CiSFGk; spf=none (imf31.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 192.55.52.120) smtp.mailfrom=chao.p.peng@linux.intel.com; dmarc=pass (policy=none) header.from=intel.com X-Rspam-User: X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 5FFCF20003 X-Stat-Signature: zjp988top41hk99y6kpi5tsfdgqyx71h X-HE-Tag: 1649841352-474382 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, Apr 12, 2022 at 10:28:21PM +0300, Kirill A. Shutemov wrote: > On Tue, Apr 12, 2022 at 09:39:25PM +0800, Chao Peng wrote: > > On Mon, Apr 11, 2022 at 06:32:33PM +0300, Kirill A. Shutemov wrote: > > > On Thu, Apr 07, 2022 at 04:05:36PM +0000, Sean Christopherson wrote: > > > > Hmm, shmem_writepage() already handles SHM_F_INACCESSIBLE by rejecting the swap, so > > > > maybe it's just the page migration path that needs to be updated? > > > > > > My early version prevented migration with -ENOTSUPP for > > > address_space_operations::migratepage(). > > > > > > What's wrong with that approach? > > > > I previously thought migratepage will not be called since we already > > marked the pages as UNMOVABLE, sounds not correct? > > Do you mean missing __GFP_MOVABLE? Yes. > I can be wrong, but I don't see that it > direclty affects if the page is migratable. It is a hint to page allocator > to group unmovable pages to separate page block and impove availablity of > higher order pages this way. Page allocator tries to allocate unmovable > pages from pages blocks that already have unmovable pages. OK, thanks. Chao > > -- > Kirill A. Shutemov