Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932119AbdC1JGK (ORCPT ); Tue, 28 Mar 2017 05:06:10 -0400 Received: from mx2.suse.de ([195.135.220.15]:40471 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932100AbdC1JGG (ORCPT ); Tue, 28 Mar 2017 05:06:06 -0400 Subject: Re: [PATCH v3 00/21] x86/xen: untangle PV and PVHVM guest support code To: Vitaly Kuznetsov , xen-devel@lists.xenproject.org References: <20170314173556.2249-1-vkuznets@redhat.com> Cc: x86@kernel.org, linux-kernel@vger.kernel.org, Boris Ostrovsky , Andrew Jones From: Juergen Gross Message-ID: <443ef6a5-a08c-0c01-555f-07e3bfbcdb25@suse.com> Date: Tue, 28 Mar 2017 11:05:43 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <20170314173556.2249-1-vkuznets@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5167 Lines: 115 On 14/03/17 18:35, Vitaly Kuznetsov wrote: > Changes since v2: > - Rebase to 4.11.0-rc1+ > - XEN_HAVE_PVMMU moved to config XEN_PV [Juergen Gross] > - .pin_vcpu kept for x86_hyper_xen_hvm to support PVH Dom0 in future > [Juergen Gross] > - 'extern' qualifiers dropped from newly introduced function prototypes > in headers [Juergen Gross] > - A couple of #includes added to address build issues with different > configs [kbuild test robot]. > - Juergen reviewed-bys added (hope they stand with the above mentioned > changes). > > The series can also be pulled from https://github.com/vittyvk/linux.git > (xen_pv_hvm_split_v3 branch). > > Some patches are known to produce checkpatch.pl WARNINGS and a couple of > ERRORs, I fixed a few (mostly in _hvm* code I split) and I refrained from > fixing the rest to make it easier to review. I think that we may leave PV > code as it is as sooner or later it will go away. > > Original description: > > I have a long-standing idea to separate PV and PVHVM code in kernel and > introduce Kconfig options to make it possible to enable the required > parts only breaking the current 'all or nothing' approach. > > Motivation: > - Xen related x86 code in kernel is rather big and it is unclear which > parts of it are required for PV, for HVM or for both. With PVH coming > into picture is becomes even more tangled. It makes it hard to > understand/audit the code. > > - In some case we may want to avoid bloating kernel by supporting Xen > guests we don't need. In particular, 90% of the code in arch/x86/xen/ is > required to support PV guests and one may require PVHVM support only. > > - PV guests are supposed to go away one day and such code separation would > help us to get ready. > > This series adds XEN_PV Kconfig option and makes it possible to build PV-only > and PVHVM-only kernels. It also makes it possible to disable Dom0 support. > > Some patches are rather big but this is mostly just moving code around, no > functional changes intended. I smoke tested it with PV-only and PVHVM-only > builds, booted and did save/restore test. I also tried the newly introduced > PVHv2 guest, it even worked! > > Vitaly Kuznetsov (21): > x86/xen: separate PV and HVM hypervisors > x86/xen: globalize have_vcpu_info_placement > x86/xen: add CONFIG_XEN_PV to Kconfig > x86/xen: split off enlighten_pvh.c > x86/xen: split off enlighten_hvm.c > x86/xen: split off enlighten_pv.c > x86/xen: split xen_smp_intr_init()/xen_smp_intr_free() > x86/xen: split xen_smp_prepare_boot_cpu() > x86/xen: split xen_cpu_die() > x86/xen: split off smp_hvm.c > x86/xen: split off smp_pv.c > x86/xen: split off mmu_hvm.c > x86/xen: split off mmu_pv.c > x86/xen: split suspend.c for PV and PVHVM guests > x86/xen: put setup.c, pmu.c and apic.c under CONFIG_XEN_PV > x86/xen: define startup_xen for XEN PV only > x86/xen: create stubs for HVM-only builds in page.h > xen/balloon: decorate PV-only parts with #ifdef CONFIG_XEN_PV > xen: create xen_create/destroy_contiguous_region() stubs for PVHVM > only builds > x86/xen: enable PVHVM-only builds > x86/xen: rename some PV-only functions in smp_pv.c > > arch/x86/include/asm/hypervisor.h | 3 +- > arch/x86/include/asm/xen/page.h | 25 + > arch/x86/kernel/cpu/hypervisor.c | 7 +- > arch/x86/kernel/process_64.c | 2 +- > arch/x86/xen/Kconfig | 33 +- > arch/x86/xen/Makefile | 16 +- > arch/x86/xen/enlighten.c | 1925 +------------------------ > arch/x86/xen/enlighten_hvm.c | 213 +++ > arch/x86/xen/enlighten_pv.c | 1522 ++++++++++++++++++++ > arch/x86/xen/enlighten_pvh.c | 115 ++ > arch/x86/xen/mmu.c | 2776 +------------------------------------ > arch/x86/xen/mmu_hvm.c | 79 ++ > arch/x86/xen/mmu_pv.c | 2635 +++++++++++++++++++++++++++++++++++ > arch/x86/xen/pmu.h | 5 + > arch/x86/xen/smp.c | 517 +------ > arch/x86/xen/smp.h | 16 + > arch/x86/xen/smp_hvm.c | 58 + > arch/x86/xen/smp_pv.c | 500 +++++++ > arch/x86/xen/suspend.c | 54 - > arch/x86/xen/suspend_hvm.c | 22 + > arch/x86/xen/suspend_pv.c | 46 + > arch/x86/xen/xen-head.S | 4 + > arch/x86/xen/xen-ops.h | 23 + > drivers/xen/balloon.c | 30 +- > include/xen/xen-ops.h | 14 + > 25 files changed, 5461 insertions(+), 5179 deletions(-) > create mode 100644 arch/x86/xen/enlighten_hvm.c > create mode 100644 arch/x86/xen/enlighten_pv.c > create mode 100644 arch/x86/xen/enlighten_pvh.c > create mode 100644 arch/x86/xen/mmu_hvm.c > create mode 100644 arch/x86/xen/mmu_pv.c > create mode 100644 arch/x86/xen/smp_hvm.c > create mode 100644 arch/x86/xen/smp_pv.c > create mode 100644 arch/x86/xen/suspend_hvm.c > create mode 100644 arch/x86/xen/suspend_pv.c > Series pushed to kernel/git/xen/tip.git for-linus-4.12 with one fixup patch added: smp_pv.c had a duplicate xen_call_function_interrupt() defined but not used. I removed it again. Juergen