KVM: Mapping guest_memfd backed memory at the host for software protected VMs
| From: | Fuad Tabba <tabba-AT-google.com> | |
| To: | kvm-AT-vger.kernel.org, linux-arm-msm-AT-vger.kernel.org, linux-mm-AT-kvack.org | |
| Subject: | [PATCH v5 0/9] KVM: Mapping guest_memfd backed memory at the host for software protected VMs | |
| Date: | Mon, 03 Mar 2025 17:10:04 +0000 | |
| Message-ID: | <20250303171013.3548775-1-tabba@google.com> | |
| Cc: | pbonzini-AT-redhat.com, chenhuacai-AT-kernel.org, mpe-AT-ellerman.id.au, anup-AT-brainfault.org, paul.walmsley-AT-sifive.com, palmer-AT-dabbelt.com, aou-AT-eecs.berkeley.edu, seanjc-AT-google.com, viro-AT-zeniv.linux.org.uk, brauner-AT-kernel.org, willy-AT-infradead.org, akpm-AT-linux-foundation.org, xiaoyao.li-AT-intel.com, yilun.xu-AT-intel.com, chao.p.peng-AT-linux.intel.com, jarkko-AT-kernel.org, amoorthy-AT-google.com, dmatlack-AT-google.com, isaku.yamahata-AT-intel.com, mic-AT-digikod.net, vbabka-AT-suse.cz, vannapurve-AT-google.com, ackerleytng-AT-google.com, mail-AT-maciej.szmigiero.name, david-AT-redhat.com, michael.roth-AT-amd.com, wei.w.wang-AT-intel.com, liam.merwick-AT-oracle.com, isaku.yamahata-AT-gmail.com, kirill.shutemov-AT-linux.intel.com, suzuki.poulose-AT-arm.com, steven.price-AT-arm.com, quic_eberman-AT-quicinc.com, quic_mnalajal-AT-quicinc.com, quic_tsoni-AT-quicinc.com, quic_svaddagi-AT-quicinc.com, quic_cvanscha-AT-quicinc.com, quic_pderrin-AT-quicinc.com, quic_pheragu-AT-quicinc.com, catalin.marinas-AT-arm.com, james.morse-AT-arm.com, yuzenghui-AT-huawei.com, oliver.upton-AT-linux.dev, maz-AT-kernel.org, will-AT-kernel.org, qperret-AT-google.com, keirf-AT-google.com, roypat-AT-amazon.co.uk, shuah-AT-kernel.org, hch-AT-infradead.org, jgg-AT-nvidia.com, rientjes-AT-google.com, jhubbard-AT-nvidia.com, fvdl-AT-google.com, hughd-AT-google.com, jthoughton-AT-google.com, peterx-AT-redhat.com, tabba-AT-google.com | |
| Archive-link: | Article |
Changes since v4 [1]: - Refactoring and fixes from comments on v4. - Rebased on Linux 6.14-rc5. The purpose of this series is to serve as a base for _restricted_ mmap() support for guest_memfd backed memory at the host [2]. It allows experimentation with what that support would be like in the safe environment of software and non-confidential VM types. For more background and for how to test this series, please refer to v2 [3]. Note that an updated version of kvmtool that works with this series is available here [4]. Cheers, /fuad [1] https://lore.kernel.org/all/20250218172500.807733-1-tabba... [2] https://lore.kernel.org/all/20250117163001.2326672-1-tabb... [3] https://lore.kernel.org/all/20250129172320.950523-1-tabba... [4] https://android-kvm.googlesource.com/kvmtool/+/refs/heads/tabba/guestmem-6.14 Fuad Tabba (9): mm: Consolidate freeing of typed folios on final folio_put() KVM: guest_memfd: Handle final folio_put() of guest_memfd pages KVM: guest_memfd: Allow host to map guest_memfd() pages KVM: guest_memfd: Handle in-place shared memory as guest_memfd backed memory KVM: x86: Mark KVM_X86_SW_PROTECTED_VM as supporting guest_memfd shared memory KVM: arm64: Refactor user_mem_abort() calculation of force_pte KVM: arm64: Handle guest_memfd()-backed guest page faults KVM: arm64: Enable mapping guest_memfd in arm64 KVM: guest_memfd: selftests: guest_memfd mmap() test when mapping is allowed arch/arm64/include/asm/kvm_host.h | 10 ++ arch/arm64/kvm/Kconfig | 1 + arch/arm64/kvm/mmu.c | 76 ++++++++----- arch/x86/include/asm/kvm_host.h | 5 + arch/x86/kvm/Kconfig | 3 +- include/linux/kvm_host.h | 26 ++++- include/linux/page-flags.h | 31 ++++++ include/uapi/linux/kvm.h | 1 + mm/debug.c | 1 + mm/swap.c | 32 +++++- tools/testing/selftests/kvm/Makefile.kvm | 1 + .../testing/selftests/kvm/guest_memfd_test.c | 75 ++++++++++++- virt/kvm/Kconfig | 5 + virt/kvm/guest_memfd.c | 105 ++++++++++++++++++ virt/kvm/kvm_main.c | 9 +- 15 files changed, 335 insertions(+), 46 deletions(-) base-commit: 7eb172143d5508b4da468ed59ee857c6e5e01da6 -- 2.48.1.711.g2feabab25a-goog