From patchwork Thu Nov 4 00:25:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 12602017 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A96F1C433FE for ; Thu, 4 Nov 2021 00:27:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9648560230 for ; Thu, 4 Nov 2021 00:27:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233679AbhKDA3u (ORCPT ); Wed, 3 Nov 2021 20:29:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52472 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233105AbhKDA2g (ORCPT ); Wed, 3 Nov 2021 20:28:36 -0400 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4B86DC061714 for ; Wed, 3 Nov 2021 17:25:59 -0700 (PDT) Received: by mail-pf1-x449.google.com with SMTP id y124-20020a623282000000b0047a09271e49so2330556pfy.16 for ; Wed, 03 Nov 2021 17:25:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=reply-to:date:message-id:mime-version:subject:from:to:cc; bh=ANJRuFa6/N/mrCRTja+awZQkxH6czfCyQf64cMZwz24=; b=WcXudEzcD22tH+HPG355uae4O/TbLzq7rMXZkNlJ48SpnvVzn/SR3sHk8XQtIKtfFy 48xyMqlSGgw1oTNAo0R/J1vgWG1e93UerRyqKUD5Qa2c4/ULYf5WGk93DChSYqJ9agNH Fa9nJgKDtBpUeiYCj9euvUxsBrArkkfyhnSH1PJXr2Gl/88Cl0a4CGn9Y4iADsm2poc/ 3MOL6YBHtOByIy6pf9yCo8zV4vME+dV5MfimvChSWTjN9iYTgoDtkS3nqw29fVsbEqKV PJA6Jv6ck5l08RPLmQ8vK5IF61aQorHOz4MISeHyAQxK20Y0bx5AN/DrWmyFqvqM0FL4 ZOMA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:date:message-id:mime-version:subject :from:to:cc; bh=ANJRuFa6/N/mrCRTja+awZQkxH6czfCyQf64cMZwz24=; b=IDQmUV0s9yHewg+gyhDZz4izn4+krK/If/kAIVOI8ZD4lbKkfcLsufi6S+4fJSfTQN HYWJ2+SyqqU4Q0xNcxl+MHpT9IhtWpqAfha2ZpkKXwCsHM3iTOKIoUSMA2iQ7QZE/tL9 FyMo3xn1wLQ5boR/c9GEHKeVeMm76f6uXv7bPO0TpI427rKXB6I2F/dwDnrV7WTdhn7k 8WoBaHstbPHTvEGElSIFAWi3KIbuDfGeEd4So0EzljRNbFpjsJuV+IXYr73bWCfnHRFg 2LG5pE81nIg6r6AfYUNpteNBKKgQ8uVIQwkV6ep/4EMbvidtF6mVOUNBcRHrVLi36ReB nFLA== X-Gm-Message-State: AOAM532Bm1x+6Y4OkEkzrnLzyRmm4Tcvx3LT6xGW5xocHzDsxSi/kTue gmMejG0LPtN8RydMAu7DzOP/mC6qaFc= X-Google-Smtp-Source: ABdhPJzlsKffFyG0Dw31UftnkkBVRPshFrq8ZrwsZvAX9gzLEmIDzXxmuc9EMVEJieZwGIMkD2hcP4GKkP4= X-Received: from seanjc.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:3e5]) (user=seanjc job=sendgmr) by 2002:a17:90a:5285:: with SMTP id w5mr261213pjh.1.1635985558096; Wed, 03 Nov 2021 17:25:58 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 4 Nov 2021 00:25:01 +0000 Message-Id: <20211104002531.1176691-1-seanjc@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.33.1.1089.g2158813163f-goog Subject: [PATCH v5.5 00/30] KVM: Scalable memslots implementation From: Sean Christopherson To: Marc Zyngier , Huacai Chen , Aleksandar Markovic , Paul Mackerras , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Paolo Bonzini Cc: James Morse , Alexandru Elisei , Suzuki K Poulose , Atish Patra , David Hildenbrand , Cornelia Huck , Claudio Imbrenda , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-mips@vger.kernel.org, kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, Ben Gardon , "Maciej S . Szmigiero" Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org This series is an iteration of Maciej's scalable memslots work. It addresses most, but not all, of my feedback from v5, hence the "5.5" moniker. Specifically, I did not touch the iteration over gfn and hva ranges as I would likely do more harm than good, especially in the gfn iterator. The core functionality of the series is unchanged from v5 (or at least, it should be). Patches "Resolve memslot ID via a hash table" and "Keep memslots in tree-based structures" are heavily reworked (the latter in particular) to provide better continuity between patches and to avoid the swap() logic when working with the "inactive" set of memslots. But again, the changes are intended to be purely cosmetic. Paolo, ideally I'd like get to patch 03 (and therefore patch 02) into 5.16. The patch technically breaks backwards compatibility with 32-bit KVM, but I'm quite confident none of the existing 32-bit architectures can possibly work. RISC-V is the one exception where it's not obvious that creating more guest memslot pages than can fit in an unsigned long won't fall on its face. Since RISC-V is new in 5.16, I'd like to get that change in before RISC-V can gain any users doing bizarre things. s390 folks, please look closely at patch 11, "KVM: s390: Use "new" memslot instead of userspace memory region". There's a subtle/weird functional change in there that I can't imagine would negatively affect userspace, but the end result is odd nonetheless. Claudio, I dropped your R-b from "KVM: Integrate gfn_to_memslot_approx() into search_memslots()" because I changed the code enough to break the s390 build at least once :-) Patches 01 and 02 are bug fixes. Patch 03 is fix of sorts to require that the total number of pages across all memslots fit in an unsigned long. The existing 32-bit KVM architectures don't correctly handle this case, and fixing those issues would quite gross and a waste of time. Patches 04-18 are cleanups throughout common KVM and all architectures to fix some warts in the memslot APIs that allow for a cleaner (IMO) of the tree-based memslots code. They also prep for more improvements that are realized in the final patch. Patches 19-28 are the core of Maciej's scalable memslots work. Patches 29-30 take advantage of the tree-based memslots to avoid creating a dummy "new" memslot on the stack, which simplifies the MOVE case and aligns it with the other three memslot update cases. v5.5 * Add all the pre- and post-work cleanups. * Rebase to kvm/queue, commit 0d7d84498fb4 ("KVM: x86: SGX must...") * Name innermost helper ____gfn_to_memslot() instead of ...approx. [Sean] * Rework hash list patch and all subsequent tree modifications to use common kvm_memslot_replace() helper. [Sean] * Rework tree-based approach to avoid swap() by always pulling the invalid memslot tree on-demand, and by relying on precise variables names and comments (for the invidual memslot pointers). v5: * https://lkml.kernel.org/r/cover.1632171478.git.maciej.szmigiero@oracle.com * Rebase onto v5.15-rc2 (torvalds/master), * Fix 64-bit division of n_memslots_pages for 32-bit KVM, * Collect Claudio's Reviewed-by tags for some of the patches. Early history can be found in the above lore link. Maciej S. Szmigiero (10): KVM: Resync only arch fields when slots_arch_lock gets reacquired KVM: x86: Use nr_memslot_pages to avoid traversing the memslots array KVM: Integrate gfn_to_memslot_approx() into search_memslots() KVM: Move WARN on invalid memslot index to update_memslots() KVM: Resolve memslot ID via a hash table instead of via a static array KVM: Use interval tree to do fast hva lookup in memslots KVM: s390: Introduce kvm_s390_get_gfn_end() KVM: Keep memslots in tree-based structures instead of array-based ones KVM: Optimize gfn lookup in kvm_zap_gfn_range() KVM: Optimize overlapping memslots check Sean Christopherson (20): KVM: Ensure local memslot copies operate on up-to-date arch-specific data KVM: Disallow user memslot with size that exceeds "unsigned long" KVM: Require total number of memslot pages to fit in an unsigned long KVM: Open code kvm_delete_memslot() into its only caller KVM: Use "new" memslot's address space ID instead of dedicated param KVM: Let/force architectures to deal with arch specific memslot data KVM: arm64: Use "new" memslot instead of userspace memory region KVM: MIPS: Drop pr_debug from memslot commit to avoid using "mem" KVM: PPC: Avoid referencing userspace memory region in memslot updates KVM: s390: Use "new" memslot instead of userspace memory region KVM: x86: Use "new" memslot instead of userspace memory region KVM: RISC-V: Use "new" memslot instead of userspace memory region KVM: Stop passing kvm_userspace_memory_region to arch memslot hooks KVM: Use prepare/commit hooks to handle generic memslot metadata updates KVM: x86: Don't assume old/new memslots are non-NULL at memslot commit KVM: s390: Skip gfn/size sanity checks on memslot DELETE or FLAGS_ONLY KVM: Don't make a full copy of the old memslot in __kvm_set_memory_region() KVM: x86: Don't call kvm_mmu_change_mmu_pages() if the count hasn't changed KVM: Wait 'til the bitter end to initialize the "new" memslot KVM: Dynamically allocate "new" memslots from the get-go arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/mmu.c | 27 +- arch/mips/kvm/Kconfig | 1 + arch/mips/kvm/mips.c | 9 +- arch/powerpc/include/asm/kvm_ppc.h | 18 +- arch/powerpc/kvm/Kconfig | 1 + arch/powerpc/kvm/book3s.c | 14 +- arch/powerpc/kvm/book3s_64_mmu_hv.c | 4 +- arch/powerpc/kvm/book3s_hv.c | 28 +- arch/powerpc/kvm/book3s_hv_nested.c | 4 +- arch/powerpc/kvm/book3s_hv_uvmem.c | 14 +- arch/powerpc/kvm/book3s_pr.c | 17 +- arch/powerpc/kvm/booke.c | 7 +- arch/powerpc/kvm/powerpc.c | 9 +- arch/riscv/kvm/mmu.c | 34 +- arch/s390/kvm/Kconfig | 1 + arch/s390/kvm/kvm-s390.c | 98 ++-- arch/s390/kvm/kvm-s390.h | 14 + arch/s390/kvm/pv.c | 4 +- arch/x86/include/asm/kvm_host.h | 1 - arch/x86/kvm/Kconfig | 1 + arch/x86/kvm/debugfs.c | 6 +- arch/x86/kvm/mmu/mmu.c | 39 +- arch/x86/kvm/x86.c | 42 +- include/linux/kvm_host.h | 240 +++++--- virt/kvm/kvm_main.c | 868 ++++++++++++++++------------ 26 files changed, 855 insertions(+), 647 deletions(-)