From patchwork Sat Sep 16 00:30:52 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 13387935 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43A97C2BA18 for ; Sat, 16 Sep 2023 00:32:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238551AbjIPAcW (ORCPT ); Fri, 15 Sep 2023 20:32:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49776 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238567AbjIPAcI (ORCPT ); Fri, 15 Sep 2023 20:32:08 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B86721724 for ; Fri, 15 Sep 2023 17:31:21 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id 3f1490d57ef6-d81d85aae7cso2235756276.0 for ; Fri, 15 Sep 2023 17:31:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1694824281; x=1695429081; darn=vger.kernel.org; h=cc:to:from:subject:message-id:mime-version:date:reply-to:from:to:cc :subject:date:message-id:reply-to; bh=d+v3gsOh/890lJDyi2atnrT8KioShqwRzfV2UUthNgY=; b=b40n4bscN2MNWMcVcR/3PuDbA1U6Kpge+yAN/Dzju6yhwIco9ZvODpk+ARmz85cfUJ JuEgdjsbhS5bLNRuBMdAOyCvUTZuTUSCvH1xoaZgHczP8t9PDQ21HYu/j2fq13oaHni3 nMCyv6qRO++OPtcVndCPH10l3M749Ml6MKZ8dzr6YGMG08xNns8CttiC/BRXTaqnCYK1 2+6LHvawxBADd2N9e8rda5Jg3Jl4kX5hqXNZtBKfgQ7TpmeNjCNnWahfGJrtAPPcLoX6 F6vlfbV/CAt/Gbb5CWVmDB/I3pUcLjDnLaoFG3mdymfsOxSMQgHOlTCXmq7a+NMrNDjY 4u4w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694824281; x=1695429081; h=cc:to:from:subject:message-id:mime-version:date:reply-to :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=d+v3gsOh/890lJDyi2atnrT8KioShqwRzfV2UUthNgY=; b=kKVA55HdjcSoSyCUTeFrdbyp2JCvOjp/iP2m5HDoImph8xU3mmL6YgxdZMz56Vluuf 22PIM9BKLSvl0yqKx1rMPO2OQJGdAQNE+lpKjvwxyQ6yhOrTbjv1Kx+Avw+Q6d47+Mz7 kL4LlJ6lhKZ7OFqU4loJZPgvwkvJ88tQPZzgDoEbP9lpXlxgcCkbOggoaTSFdTlrK7CH n3AZ201UycUZxtdIWWXvW9UCq8SvQ5GQI2djkGI49DV5Eahe8wIMJ++YxqdCJV6WWeGO Djd6p4B6rJrgLPRA0m9vvkG4QbgrcNYUaiCc7Sel66tq3OSts8OBEbdvSKqn71yGiiJl k8uQ== X-Gm-Message-State: AOJu0YwcEDz4pyQfYh494bf0Ju53z8exblf8HSZ7yFVnHouUyywvM1lg Oo5FvP0TzbhsTgQRObED2SaAE+EQGnQ= X-Google-Smtp-Source: AGHT+IHwIfgzmidHRVnFwyjq5xxKkTsUmzHH5rOWwrOCjAKfiyYkOEMh1VsVt19qwGFmjKKFISeZq6Tx90c= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a25:554:0:b0:d47:3d35:1604 with SMTP id 81-20020a250554000000b00d473d351604mr95244ybf.2.1694824280932; Fri, 15 Sep 2023 17:31:20 -0700 (PDT) Reply-To: Sean Christopherson Date: Fri, 15 Sep 2023 17:30:52 -0700 Mime-Version: 1.0 X-Mailer: git-send-email 2.42.0.459.ge4e396fd5e-goog Message-ID: <20230916003118.2540661-1-seanjc@google.com> Subject: [PATCH 00/26] KVM: vfio: Hide KVM internals from others From: Sean Christopherson To: Catalin Marinas , Will Deacon , Marc Zyngier , Oliver Upton , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, Peter Zijlstra , Arnaldo Carvalho de Melo , Sean Christopherson , Paolo Bonzini , Tony Krowiak , Halil Pasic , Jason Herne , Harald Freudenberger , Alex Williamson , Andy Lutomirski Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, kvm@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Anish Ghulati , Venkatesh Srinivas , Andrew Thornton Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org This is a borderline RFC series to hide KVM's internals from the rest of the kernel, where "internals" means data structures, enums, #defines, APIs, etc. that are intended to be KVM-only, but are exposed everywhere due to kvm_host.h (and other headers) living in the global include paths. The motiviation for hiding KVM's internals is to allow *safely* loading a "new" KVM module without having to reboot the host. Where "new" doesn't have to be strictly newer, just a different incarnation of KVM. Hiding KVM's internals means those assets can change across KVM instances without breaking things, e.g. would allow modifying the layout of struct kvm_vcpu to introduce new fields related to a new feature or mitigation for hardware bugs. The end goal for all of this is to allow loading and running multiple instances of KVM (the module) simultaneously on a single host, e.g. to deploy fixes, mitigations, and/or new features without having to drain all VMs from the host. For now, the immediate goal is to get KVM to a state where KVM x86 doesn't expose anything to the broader world that isn't intended for external consumption, e.g. the page write-tracking APIs used by KVM-GT. I say this is borderline RFC because I don't think I've "formally" proposed the idea of hiding KVM internals before now. I decided not to tag this RFC because the changes ended up being not _that_ invasive, and everything before the last six patches is worthwhile even if hiding internals is ultimately rejected (IMO). This would ideally be ~5 separate series, and I certainly have no objection if that's how we want to get this stuff merged. E.g. (1) VFIO cleanups, (2) drop HAVE_KVM, (3) clean up makefiles, (4) x86 perf cleanup, and (5) final push for hiding state. The HAVE_KVM and virt/kvm include stuff isn't strictly necessary, but I included them here because they're relatively minor (in the grand scheme). We've explore several alternatives to the #ifdef __KVM__ approach, and they all sucked, hard. What I really wanted (and still want) to do, is to bury the bulk of kvm_host.h (and other KVM headers) in virt/kvm, but every attempt to do that ended in flames. Even with the __KVM__ guards in place, each architecture's kvm_host.h is too intertwined with the common kvm_host.h, and trying to extract small-ish pieces just doesn't work (each patch inevitably snowballed into a gigantic beast). The other idea we considered (which I thought of, and feel dirty for even proposing it internally), is to move all headers under virt/kvm, add virt/kvm/include to the global header path, and then have KVM x86 omit virt/kvm/include when configured to hide KVM internals. I hate this idea because it sets a bad precedent, and requires a lot of file movement without providing any benefit to other architectures. E.g. I hope that guarding KVM internals with #ifdef __KVM__ will allow us to slowly clean things up so that some day KVM only exposes a handful of APIs to the rest of the kernel (probably a pipe dream). Anish Ghulati (1): KVM: arm64: Move arm_{psci,hypercalls}.h to an internal KVM path Sean Christopherson (25): vfio: Wrap KVM helpers with CONFIG_KVM instead of CONFIG_HAVE_KVM vfio: Move KVM get/put helpers to colocate it with other KVM related code virt: Declare and define vfio_file_set_kvm() iff CONFIG_KVM is enabled vfio: Add struct to hold KVM assets and dedup group vs. iommufd code vfio: KVM: Pass get/put helpers from KVM to VFIO, don't do circular lookup KVM: Drop CONFIG_KVM_VFIO and just look at KVM+VFIO x86/idt: Wrap KVM logic with CONFIG_KVM instead of CONFIG_HAVE_KVM KVM: x86: Stop selecting and depending on HAVE_KVM KVM: arm64: Stop selecting and depending on HAVE_KVM KVM: s390: Stop selecting and depending on HAVE_KVM KVM: MIPS: Make HAVE_KVM a MIPS-only Kconfig KVM: arm64: Include KVM headers to get forward declarations KVM: arm64: Move ARM specific headers in include/kvm to arch directory KVM: Move include/kvm/iodev.h to include/linux as kvm_iodev.h KVM: MIPS: Stop adding virt/kvm to the arch include path KVM: PPC: Stop adding virt/kvm to the arch include path KVM: s390: Stop adding virt/kvm to the arch include path KVM: Standardize include paths across all architectures perf/x86: KVM: Have perf define a dedicated struct for getting guest PEBS data entry/kvm: Drop @vcpu param from arch_xfer_to_guest_mode_handle_work() entry/kvm: KVM: Move KVM details related to signal/-EINTR into KVM proper KVM: arm64: Move and consolidate "public" functions in asm/kvm_host.h powerpc/xics: Move declaration of xics_wake_cpu() out of kvm_ppc.h KVM: PPC: Rearrange code in kvm_ppc.h to isolate "public" information KVM: Hide KVM internal data structures and values from kernel at-large MAINTAINERS | 1 - arch/arm64/Kconfig | 1 - .../arm64/include/asm/kvm_arch_timer.h | 2 + arch/arm64/include/asm/kvm_emulate.h | 3 + arch/arm64/include/asm/kvm_host.h | 57 ++-- arch/arm64/include/asm/kvm_mmu.h | 4 + .../arm64/include/asm/kvm_pmu.h | 2 + .../arm64/include/asm/kvm_vgic.h | 2 +- arch/arm64/kernel/asm-offsets.c | 2 + arch/arm64/kvm/Kconfig | 2 - arch/arm64/kvm/Makefile | 2 - arch/arm64/kvm/arch_timer.c | 5 +- arch/arm64/kvm/arm.c | 9 +- {include => arch/arm64}/kvm/arm_hypercalls.h | 0 {include => arch/arm64}/kvm/arm_psci.h | 0 arch/arm64/kvm/guest.c | 2 +- arch/arm64/kvm/handle_exit.c | 2 +- arch/arm64/kvm/hyp/Makefile | 4 +- arch/arm64/kvm/hyp/include/hyp/switch.h | 4 +- arch/arm64/kvm/hyp/nvhe/Makefile | 3 +- arch/arm64/kvm/hyp/nvhe/switch.c | 4 +- arch/arm64/kvm/hyp/vhe/Makefile | 2 +- arch/arm64/kvm/hyp/vhe/switch.c | 4 +- arch/arm64/kvm/hypercalls.c | 4 +- arch/arm64/kvm/pmu-emul.c | 6 +- arch/arm64/kvm/psci.c | 4 +- arch/arm64/kvm/pvtime.c | 2 +- arch/arm64/kvm/reset.c | 3 +- arch/arm64/kvm/trace_arm.h | 2 +- arch/arm64/kvm/trng.c | 2 +- arch/arm64/kvm/vgic/vgic-debug.c | 2 +- arch/arm64/kvm/vgic/vgic-init.c | 2 +- arch/arm64/kvm/vgic/vgic-irqfd.c | 2 +- arch/arm64/kvm/vgic/vgic-kvm-device.c | 2 +- arch/arm64/kvm/vgic/vgic-mmio-v2.c | 4 +- arch/arm64/kvm/vgic/vgic-mmio-v3.c | 4 +- arch/arm64/kvm/vgic/vgic-mmio.c | 6 +- arch/arm64/kvm/vgic/vgic-v2.c | 2 +- arch/arm64/kvm/vgic/vgic-v3.c | 2 +- arch/mips/include/asm/kvm_host.h | 5 +- arch/mips/kernel/asm-offsets.c | 2 + arch/mips/kvm/Kconfig | 3 + arch/mips/kvm/Makefile | 2 - arch/powerpc/include/asm/kvm_book3s.h | 3 + arch/powerpc/include/asm/kvm_book3s_64.h | 2 + arch/powerpc/include/asm/kvm_booke.h | 4 + arch/powerpc/include/asm/kvm_host.h | 7 +- arch/powerpc/include/asm/kvm_ppc.h | 306 +++++++++--------- arch/powerpc/include/asm/xics.h | 3 + arch/powerpc/kernel/asm-offsets.c | 1 + arch/powerpc/kvm/Kconfig | 1 - arch/powerpc/kvm/Makefile | 2 - arch/powerpc/kvm/mpic.c | 2 +- arch/riscv/include/asm/kvm_host.h | 3 + arch/riscv/kernel/asm-offsets.c | 1 + arch/riscv/kvm/Makefile | 2 - arch/riscv/kvm/aia_aplic.c | 2 +- arch/riscv/kvm/aia_imsic.c | 2 +- arch/riscv/kvm/vcpu.c | 2 +- arch/s390/Kconfig | 1 - arch/s390/include/asm/kvm_host.h | 7 +- arch/s390/kernel/asm-offsets.c | 1 + arch/s390/kvm/Kconfig | 2 - arch/s390/kvm/Makefile | 2 - arch/x86/Kconfig | 1 - arch/x86/events/core.c | 5 +- arch/x86/events/intel/core.c | 18 +- arch/x86/events/perf_event.h | 3 +- arch/x86/include/asm/hardirq.h | 2 +- arch/x86/include/asm/idtentry.h | 2 +- arch/x86/include/asm/irq.h | 2 +- arch/x86/include/asm/irq_vectors.h | 2 +- arch/x86/include/asm/kvm_host.h | 12 +- arch/x86/include/asm/perf_event.h | 12 +- arch/x86/kernel/idt.c | 2 +- arch/x86/kernel/irq.c | 4 +- arch/x86/kvm/Kconfig | 3 - arch/x86/kvm/Makefile | 1 - arch/x86/kvm/i8254.h | 2 +- arch/x86/kvm/ioapic.h | 2 +- arch/x86/kvm/irq.h | 2 +- arch/x86/kvm/lapic.h | 2 +- arch/x86/kvm/vmx/pmu_intel.c | 16 +- arch/x86/kvm/vmx/vmx.c | 11 +- arch/x86/kvm/vmx/vmx.h | 2 +- arch/x86/kvm/x86.c | 3 +- drivers/s390/crypto/vfio_ap_drv.c | 1 + drivers/s390/crypto/vfio_ap_ops.c | 2 + drivers/vfio/device_cdev.c | 9 +- drivers/vfio/group.c | 18 +- drivers/vfio/vfio.h | 26 +- drivers/vfio/vfio_main.c | 139 ++++---- include/linux/entry-kvm.h | 10 +- include/linux/kvm_host.h | 17 +- include/{kvm/iodev.h => linux/kvm_iodev.h} | 0 include/linux/kvm_types.h | 3 + include/linux/vfio.h | 6 +- include/trace/events/kvm.h | 5 + kernel/entry/kvm.c | 13 +- scripts/gdb/linux/constants.py.in | 2 +- scripts/gdb/linux/interrupts.py | 2 +- tools/arch/x86/include/asm/irq_vectors.h | 2 +- virt/kvm/Kconfig | 6 - virt/kvm/Makefile.kvm | 6 +- virt/kvm/coalesced_mmio.c | 3 +- virt/kvm/eventfd.c | 2 +- virt/kvm/kvm_main.c | 3 +- virt/kvm/vfio.c | 9 +- virt/kvm/vfio.h | 2 +- 109 files changed, 489 insertions(+), 440 deletions(-) rename include/kvm/arm_arch_timer.h => arch/arm64/include/asm/kvm_arch_timer.h (98%) rename include/kvm/arm_pmu.h => arch/arm64/include/asm/kvm_pmu.h (99%) rename include/kvm/arm_vgic.h => arch/arm64/include/asm/kvm_vgic.h (99%) rename {include => arch/arm64}/kvm/arm_hypercalls.h (100%) rename {include => arch/arm64}/kvm/arm_psci.h (100%) rename include/{kvm/iodev.h => linux/kvm_iodev.h} (100%) base-commit: 0bb80ecc33a8fb5a682236443c1e740d5c917d1d