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=-6.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 659D1C43461 for ; Fri, 4 Sep 2020 08:42:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3926B2087C for ; Fri, 4 Sep 2020 08:42:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=citrix.com header.i=@citrix.com header.b="VJH4hc0F" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729975AbgIDImq (ORCPT ); Fri, 4 Sep 2020 04:42:46 -0400 Received: from esa2.hc3370-68.iphmx.com ([216.71.145.153]:41414 "EHLO esa2.hc3370-68.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726425AbgIDImn (ORCPT ); Fri, 4 Sep 2020 04:42:43 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=citrix.com; s=securemail; t=1599208963; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=xLTKJpKu0Qb9zvtBCrFuNtN0uryK+Cr91K+kobkwuTU=; b=VJH4hc0FPhmjgut4SqbjI7CokB2tWO7ccaoYtbQZPeKo8AETmu6DDSfU uWYiCukAb9/QxH/zjCH7IM1NY4yc0cSjqalXiTWZtLKDIuq1sktwsuruY 5IQfNXZ3C6lgKNwHAwXcVM0nkJ4971tSTcYWex88WkjAiPBi2OCjDiGg7 s=; Authentication-Results: esa2.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none IronPort-SDR: h5tULVCP7TU027wl9AXL6ZQ6VRDTloWxNR1nakHosYYzU8awVMN14syMLQayv9uBc8sCFQrpo9 MPsKynxlrUeIV2fLzkBXNB2LUVlnfaK5CMhGyHMRLQdBCX/4b+icfvHWVHnKE5oWjtKeDrh1Vt bxXRH4/LS58XLNlEMXW3QOoEhr480K9hH8A115xIrprTnfo3A9FB8sMcgG1DSn17YgpLbZzhqS 8hNixQHRV8a/451xr8mSb/Ts/liLTz0NYAxGPT2Wdtw9MukJ2GIKcdJVYScDS0jHAxjENA9Gp1 +EE= X-SBRS: 2.7 X-MesageID: 26001821 X-Ironport-Server: esa2.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.76,389,1592884800"; d="scan'208";a="26001821" Date: Fri, 4 Sep 2020 10:42:29 +0200 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: =?utf-8?B?SsO8cmdlbiBHcm/Dnw==?= CC: , Oleksandr Andrushchenko , David Airlie , "Daniel Vetter" , Boris Ostrovsky , Stefano Stabellini , Dan Carpenter , Wei Liu , Yan Yankovskyi , , , , David Hildenbrand , Michal Hocko , Dan Williams Subject: Re: [PATCH v5 3/3] xen: add helpers to allocate unpopulated memory Message-ID: <20200904084229.GN753@Air-de-Roger> References: <20200901083326.21264-1-roger.pau@citrix.com> <20200901083326.21264-4-roger.pau@citrix.com> <20200903163837.GM753@Air-de-Roger> <6fd73d30-5525-7f00-1e9c-d7bb96ea34a6@suse.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <6fd73d30-5525-7f00-1e9c-d7bb96ea34a6@suse.com> X-ClientProxiedBy: AMSPEX02CAS01.citrite.net (10.69.22.112) To FTLPEX02CL06.citrite.net (10.13.108.179) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Sep 04, 2020 at 09:00:18AM +0200, Jürgen Groß wrote: > On 03.09.20 18:38, Roger Pau Monné wrote: > > On Thu, Sep 03, 2020 at 05:30:07PM +0200, Jürgen Groß wrote: > > > On 01.09.20 10:33, Roger Pau Monne wrote: > > > > To be used in order to create foreign mappings. This is based on the > > > > ZONE_DEVICE facility which is used by persistent memory devices in > > > > order to create struct pages and kernel virtual mappings for the IOMEM > > > > areas of such devices. Note that on kernels without support for > > > > ZONE_DEVICE Xen will fallback to use ballooned pages in order to > > > > create foreign mappings. > > > > > > > > The newly added helpers use the same parameters as the existing > > > > {alloc/free}_xenballooned_pages functions, which allows for in-place > > > > replacement of the callers. Once a memory region has been added to be > > > > used as scratch mapping space it will no longer be released, and pages > > > > returned are kept in a linked list. This allows to have a buffer of > > > > pages and prevents resorting to frequent additions and removals of > > > > regions. > > > > > > > > If enabled (because ZONE_DEVICE is supported) the usage of the new > > > > functionality untangles Xen balloon and RAM hotplug from the usage of > > > > unpopulated physical memory ranges to map foreign pages, which is the > > > > correct thing to do in order to avoid mappings of foreign pages depend > > > > on memory hotplug. > > > > > > > > Note the driver is currently not enabled on Arm platforms because it > > > > would interfere with the identity mapping required on some platforms. > > > > > > > > Signed-off-by: Roger Pau Monné > > > > > > Sorry, I just got a build error for x86 32-bit build: > > > > > > WARNING: unmet direct dependencies detected for ZONE_DEVICE > > > Depends on [n]: MEMORY_HOTPLUG [=n] && MEMORY_HOTREMOVE [=n] && > > > SPARSEMEM_VMEMMAP [=n] && ARCH_HAS_PTE_DEVMAP [=n] > > > Selected by [y]: > > > - XEN_UNPOPULATED_ALLOC [=y] && XEN [=y] && X86 [=y] > > > GEN Makefile > > > CC kernel/bounds.s > > > CALL /home/gross/korg/src/scripts/atomic/check-atomics.sh > > > UPD include/generated/bounds.h > > > CC arch/x86/kernel/asm-offsets.s > > > In file included from /home/gross/korg/src/include/linux/mmzone.h:19:0, > > > from /home/gross/korg/src/include/linux/gfp.h:6, > > > from /home/gross/korg/src/include/linux/slab.h:15, > > > from /home/gross/korg/src/include/linux/crypto.h:19, > > > from /home/gross/korg/src/arch/x86/kernel/asm-offsets.c:9: > > > /home/gross/korg/src/include/linux/page-flags-layout.h:95:2: error: #error > > > "Not enough bits in page flags" > > > #error "Not enough bits in page flags" > > > ^~~~~ > > > make[2]: *** [/home/gross/korg/src/scripts/Makefile.build:114: > > > arch/x86/kernel/asm-offsets.s] Error 1 > > > make[1]: *** [/home/gross/korg/src/Makefile:1175: prepare0] Error 2 > > > make[1]: Leaving directory '/home/gross/korg/x8632' > > > make: *** [Makefile:185: __sub-make] Error 2 > > > > Sorry for this. I've tested a 32bit build but I think it was before > > the last Kconfig changes. I'm a little unsure how to solve this, as > > ZONE_DEVICE doesn't select the required options for it to run, but > > rather depends on them to be available. > > > > You can trigger something similar on x86-64 by doing: > > > > $ make ARCH=x86_64 xen.config > > Using .config as base > > Merging ./kernel/configs/xen.config > > Merging ./arch/x86/configs/xen.config > > # > > # merged configuration written to .config (needs make) > > # > > scripts/kconfig/conf --olddefconfig Kconfig > > > > WARNING: unmet direct dependencies detected for ZONE_DEVICE > > Depends on [n]: MEMORY_HOTPLUG [=y] && MEMORY_HOTREMOVE [=n] && SPARSEMEM_VMEMMAP [=y] && ARCH_HAS_PTE_DEVMAP [=y] > > Selected by [y]: > > - XEN_UNPOPULATED_ALLOC [=y] && XEN [=y] && X86_64 [=y] > > # > > # configuration written to .config > > # > > > > I think the only solution is to have XEN_UNPOPULATED_ALLOC depend on > > ZONE_DEVICE rather than select it? > > Yes, I think so. > > I've folded that in and now build is fine. Thanks, I assume no further action is needed on my side. Roger.