This v4 series still carry both QEMU guest memfd support and QEMU TDX support. Because TDX is going to be the first user of guest memfd in QEMU, put them together can provide us a full picture of how they work.
KVM provides guest memfd, which cannot be mapped, read, or written by userspace. It's designed to serve as private memory for confidential VMs, like Intel TDX and AMD sev-snp. Patches 1 - 9 add support of guest memfd into QEMU, associating it with RAMBlock. For the VM types that require private memory (see tdx_kvm_init() in patch 14), QEMU will automatically create guest memfd for each RAM backend. Follwoing patches 10 to 66, enables TDX support to allow creating and booting a TD (TDX VM) with QEMU. This series needs to work with KVM TDX v18 series: https://lore.kernel.org/all/cover.1705965634.git.isaku.yamah...@intel.com/T/#u (TDX host kernel support and guest memfd KVM support lands in Linux v6.8-rc1.) === This series is also available in github: https://github.com/intel/qemu-tdx/tree/tdx-qemu-upstream-v4 It's based on several patches that haven't get merged: https://lore.kernel.org/qemu-devel/20231007065819.27498-1-xiaoyao...@intel.com/ https://lore.kernel.org/qemu-devel/20240125023328.2520888-1-xiaoyao...@intel.com/ https://lore.kernel.org/all/20240125024016.2521244-1-xiaoyao...@intel.com/ Luckily, the absence of them doesn't block applying this series nor affecting the functionality. == Limitation and future work == - Readonly memslot TDX only support readonly (write protection) memslot for shared memory, but not for private memory. For simplicity, just mark readonly memslot not supported entirely for TDX. - CPU model We cannot create a TD with arbitrary CPU model like what for non-TDX VMs, because only a subset of features can be configured for TD. - It's recommended to use '-cpu host' to create TD; - '+feature/-feature' might not work as expected; future work: To introduce specific CPU model for TDs and enhance ±features for TDs. - gdb suppport gdb support to debug a TD of off-debug mode is future work. === Main changes in v4: guset memfd part: - Drop the patch that supports KVM_GUEST_MEMFD_ALLOW_HUGEPAGE flag because KVM side leaves it as future work; - send patch "physmem: replace function name with __func__ in ram_block_discard_range()" separately; - drop ram_block_convert_range() and open code it instead. - move the supported attribute bit check into kvm_set_memory_attributes() (per request from Wei) - Clarify more for the desgin consideration in the commit messages TDX part: - Re-implement get-quote support by introduing TdxQuoteGenerator object and make the socket communication non-blocking; (per Daniel) - Various code and doc refinement; v3: https://lore.kernel.org/qemu-devel/20231115071519.2864957-1-xiaoyao...@intel.com/ Main changes in v3: gmem memfd part: - Since KVM side renamed gmem to guest_memfd in the uapi, this version renames it accordingly; - Drop the 'private' property of memory backend. (see comment[1]) Now QEMU decides whether need to create guest memfd based on specific vm type (or specific VM implementation, please see patch *X* and *Y*); - Drop sw_protected_vm implementation; TDX part: - improve the error report in various patches by utilizing 'errp'; - drop the vm-type interface; - rename __tdx_ioctl() to tdx_ioctl_internal(); - refine the description of 'sept-ve-disable' in qom.json; - use base64 for mrconfigif/mrowner/mrownerconfig instread of hex-string; - use type SocketAddress for quote-generation-service; [1] https://lore.kernel.org/qemu-devel/a1e34896-c46d-c87c-0fda-971bbf3dc...@redhat.com/ Chao Peng (3): kvm: Enable KVM_SET_USER_MEMORY_REGION2 for memslot kvm: handle KVM_EXIT_MEMORY_FAULT i386/tdx: register TDVF as private memory Isaku Yamahata (14): trace/kvm: Add trace for page convertion between shared and private i386/tdx: Make sept_ve_disable set by default i386/tdx: Support user configurable mrconfigid/mrowner/mrownerconfig kvm/tdx: Don't complain when converting vMMIO region to shared kvm/tdx: Ignore memory conversion to shared of unassigned region i386/tdvf: Introduce function to parse TDVF metadata i386/tdx: Add TDVF memory via KVM_TDX_INIT_MEM_REGION i386/tdx: handle TDG.VP.VMCALL<SetupEventNotifyInterrupt> i386/tdx: handle TDG.VP.VMCALL<GetQuote> i386/tdx: handle TDG.VP.VMCALL<MapGPA> hypercall pci-host/q35: Move PAM initialization above SMRAM initialization q35: Introduce smm_ranges property for q35-pci-host hw/i386: add option to forcibly report edge trigger in acpi tables i386/tdx: Don't synchronize guest tsc for TDs Sean Christopherson (2): i386/kvm: Move architectural CPUID leaf generation to separate helper i386/tdx: Don't get/put guest state for TDX VMs Xiaoyao Li (47): linux-headers: Update to Linux v6.8-rc1 RAMBlock: Add support of KVM private guest memfd HostMem: Add mechanism to opt in kvm guest memfd via MachineState trace/kvm: Split address space and slot id in trace_kvm_set_user_memory() kvm: Introduce support for memory_attributes physmem: Introduce ram_block_discard_guest_memfd_range() *** HACK *** linux-headers: Update headers to pull in TDX API changes i386: Introduce tdx-guest object target/i386: Implement mc->kvm_type() to get VM type target/i386: Introduce kvm_confidential_guest_init() i386/tdx: Implement tdx_kvm_init() to initialize TDX VM context i386/tdx: Get tdx_capabilities via KVM_TDX_CAPABILITIES i386/tdx: Introduce is_tdx_vm() helper and cache tdx_guest object i386/tdx: Adjust the supported CPUID based on TDX restrictions i386/tdx: Make Intel-PT unsupported for TD guest i386/tdx: Update tdx_cpuid_lookup[].tdx_fixed0/1 by tdx_caps.cpuid_config[] i386/tdx: Integrate tdx_caps->xfam_fixed0/1 into tdx_cpuid_lookup i386/tdx: Integrate tdx_caps->attrs_fixed0/1 to tdx_cpuid_lookup kvm: Introduce kvm_arch_pre_create_vcpu() i386/tdx: Initialize TDX before creating TD vcpus i386/tdx: Add property sept-ve-disable for tdx-guest object i386/tdx: Wire CPU features up with attributes of TD guest i386/tdx: Validate TD attributes i386/tdx: Implement user specified tsc frequency i386/tdx: Set kvm_readonly_mem_enabled to false for TDX VM kvm/memory: Introduce the infrastructure to set the default shared/private value i386/tdx: Make memory type private by default i386/tdx: Parse TDVF metadata for TDX VM i386/tdx: Skip BIOS shadowing setup i386/tdx: Don't initialize pc.rom for TDX VMs i386/tdx: Track mem_ptr for each firmware entry of TDVF i386/tdx: Track RAM entries for TDX VM headers: Add definitions from UEFI spec for volumes, resources, etc... i386/tdx: Setup the TD HOB list memory: Introduce memory_region_init_ram_guest_memfd() i386/tdx: Call KVM_TDX_INIT_VCPU to initialize TDX vcpu i386/tdx: Finalize TDX VM i386/tdx: Handle TDG.VP.VMCALL<REPORT_FATAL_ERROR> i386/tdx: Wire TDX_REPORT_FATAL_ERROR with GuestPanic facility i386/tdx: Disable SMM for TDX VMs i386/tdx: Disable PIC for TDX VMs i386/tdx: Don't allow system reset for TDX VMs i386/tdx: LMCE is not supported for TDX hw/i386: add eoi_intercept_unsupported member to X86MachineState i386/tdx: Only configure MSR_IA32_UCODE_REV in kvm_init_msrs() for TDs i386/tdx: Skip kvm_put_apicbase() for TDs docs: Add TDX documentation accel/kvm/kvm-all.c | 278 +++- accel/kvm/trace-events | 3 +- accel/stubs/kvm-stub.c | 5 + backends/hostmem-file.c | 1 + backends/hostmem-memfd.c | 1 + backends/hostmem-ram.c | 1 + backends/hostmem.c | 1 + configs/devices/i386-softmmu/default.mak | 1 + docs/system/confidential-guest-support.rst | 1 + docs/system/i386/tdx.rst | 113 ++ docs/system/target-i386.rst | 1 + hw/core/machine.c | 5 + hw/i386/Kconfig | 6 + hw/i386/acpi-build.c | 99 +- hw/i386/acpi-common.c | 50 +- hw/i386/meson.build | 1 + hw/i386/pc.c | 21 +- hw/i386/pc_q35.c | 2 + hw/i386/pc_sysfw.c | 7 + hw/i386/tdvf-hob.c | 147 ++ hw/i386/tdvf-hob.h | 24 + hw/i386/tdvf.c | 200 +++ hw/i386/x86.c | 51 +- hw/pci-host/q35.c | 61 +- include/exec/cpu-common.h | 2 + include/exec/memory.h | 33 +- include/exec/ram_addr.h | 2 +- include/exec/ramblock.h | 1 + include/hw/boards.h | 2 + include/hw/i386/pc.h | 1 + include/hw/i386/tdvf.h | 58 + include/hw/i386/x86.h | 2 + include/hw/pci-host/q35.h | 1 + include/standard-headers/drm/drm_fourcc.h | 10 +- include/standard-headers/linux/ethtool.h | 41 +- .../standard-headers/linux/virtio_config.h | 8 +- include/standard-headers/linux/virtio_pci.h | 68 + include/standard-headers/linux/virtio_pmem.h | 7 + include/standard-headers/uefi/uefi.h | 198 +++ include/sysemu/hostmem.h | 1 + include/sysemu/kvm.h | 8 + include/sysemu/kvm_int.h | 2 + linux-headers/asm-generic/unistd.h | 15 +- linux-headers/asm-loongarch/kvm.h | 1 + linux-headers/asm-mips/mman.h | 2 +- linux-headers/asm-mips/unistd_n32.h | 5 + linux-headers/asm-mips/unistd_n64.h | 5 + linux-headers/asm-mips/unistd_o32.h | 5 + linux-headers/asm-powerpc/unistd_32.h | 5 + linux-headers/asm-powerpc/unistd_64.h | 5 + linux-headers/asm-riscv/kvm.h | 13 + linux-headers/asm-s390/unistd_32.h | 5 + linux-headers/asm-s390/unistd_64.h | 5 + linux-headers/asm-x86/kvm.h | 94 ++ linux-headers/asm-x86/unistd_32.h | 5 + linux-headers/asm-x86/unistd_64.h | 5 + linux-headers/asm-x86/unistd_x32.h | 5 + linux-headers/linux/iommufd.h | 79 + linux-headers/linux/kvm.h | 229 +-- linux-headers/linux/userfaultfd.h | 29 +- linux-headers/linux/vfio.h | 1 + qapi/qom.json | 33 + qapi/run-state.json | 28 +- system/memory.c | 45 + system/physmem.c | 47 +- system/runstate.c | 54 + target/i386/cpu-internal.h | 9 + target/i386/cpu.c | 12 - target/i386/cpu.h | 21 + target/i386/kvm/kvm-cpu.c | 5 + target/i386/kvm/kvm.c | 611 +++++--- target/i386/kvm/kvm_i386.h | 6 + target/i386/kvm/meson.build | 2 + target/i386/kvm/tdx-quote-generator.c | 170 ++ target/i386/kvm/tdx-quote-generator.h | 95 ++ target/i386/kvm/tdx-stub.c | 23 + target/i386/kvm/tdx.c | 1373 +++++++++++++++++ target/i386/kvm/tdx.h | 82 + target/i386/sev.c | 1 - target/i386/sev.h | 2 + 80 files changed, 4156 insertions(+), 501 deletions(-) create mode 100644 docs/system/i386/tdx.rst create mode 100644 hw/i386/tdvf-hob.c create mode 100644 hw/i386/tdvf-hob.h create mode 100644 hw/i386/tdvf.c create mode 100644 include/hw/i386/tdvf.h create mode 100644 include/standard-headers/uefi/uefi.h create mode 100644 target/i386/kvm/tdx-quote-generator.c create mode 100644 target/i386/kvm/tdx-quote-generator.h create mode 100644 target/i386/kvm/tdx-stub.c create mode 100644 target/i386/kvm/tdx.c create mode 100644 target/i386/kvm/tdx.h -- 2.34.1
