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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 983EEC2D0EA for ; Wed, 8 Apr 2020 15:38:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6E4B6206F7 for ; Wed, 8 Apr 2020 15:38:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="gBMMD0VV" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729178AbgDHPiI (ORCPT ); Wed, 8 Apr 2020 11:38:08 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:42844 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728895AbgDHPiI (ORCPT ); Wed, 8 Apr 2020 11:38:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=zXlIsbDM28OKmK+7j6iTmvR4wjllvC+TzshTZOZR7TU=; b=gBMMD0VVRRKgOhHzpjDt/lZU1Y u9BILt8VLhw0sO34uaQF8z0/PQuXdH0k8rq6aufu410mYc/h3uYsHE3q9jGtAR4M+g6usA+9c6hXK qRLaLBonqPUOIZaYwx8mMo+2EsEG9nTiAccNRbs6mfHNotxOLNwE+DlKy1V2XzHirfFfsMPOVzUym kj+8W0aL1LC5SGUCy/9LavI/NBI3tZTJ8tgBbvnAEsg8PZoPaY6ZqgBKJJoDlEFMhPCgeRUq/t2tJ UNV8tw5S5/pX84WeHyxnsmLcEBTrdKEA6VvzmozcQ0Sa3ZoJrnu5VhBf+PUP8I8OdfHleFuFcY7pQ OYfbsiKQ==; Received: from [2601:1c0:6280:3f0::19c2] by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jMCm9-0006Y5-CG; Wed, 08 Apr 2020 15:38:07 +0000 Subject: Re: [PATCH 10/28] mm: only allow page table mappings for built-in zsmalloc To: Christoph Hellwig , Matthew Wilcox Cc: Peter Zijlstra , Andrew Morton , "K. Y. Srinivasan" , Haiyang Zhang , Stephen Hemminger , Wei Liu , x86@kernel.org, David Airlie , Daniel Vetter , Laura Abbott , Sumit Semwal , Sakari Ailus , Minchan Kim , Nitin Gupta , Robin Murphy , Christophe Leroy , linuxppc-dev@lists.ozlabs.org, linux-hyperv@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, linux-arm-kernel@lists.infradead.org, linux-s390@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org References: <20200408115926.1467567-1-hch@lst.de> <20200408115926.1467567-11-hch@lst.de> <20200408151203.GN20730@hirez.programming.kicks-ass.net> <20200408151519.GQ21484@bombadil.infradead.org> <20200408153602.GA28081@lst.de> From: Randy Dunlap Message-ID: Date: Wed, 8 Apr 2020 08:37:59 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <20200408153602.GA28081@lst.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-hyperv-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-hyperv@vger.kernel.org On 4/8/20 8:36 AM, Christoph Hellwig wrote: > On Wed, Apr 08, 2020 at 08:15:19AM -0700, Matthew Wilcox wrote: >>>>> config ZSMALLOC_PGTABLE_MAPPING >>>>> bool "Use page table mapping to access object in zsmalloc" >>>>> - depends on ZSMALLOC >>>>> + depends on ZSMALLOC=y >>>> >>>> It's a bool so this shouldn't matter... not needed. >>> >>> My mm/Kconfig has: >>> >>> config ZSMALLOC >>> tristate "Memory allocator for compressed pages" >>> depends on MMU >>> >>> which I think means it can be modular, no? >> >> Randy means that ZSMALLOC_PGTABLE_MAPPING is a bool, so I think hch's patch >> is wrong ... if ZSMALLOC is 'm' then ZSMALLOC_PGTABLE_MAPPING would become >> 'n' instead of 'y'. > > In Linus' tree you can select PGTABLE_MAPPING=y with ZSMALLOC=m, > and that fits my understanding of the kbuild language. With this > patch I can't anymore. > Makes sense. thanks. -- ~Randy