Gunyah is a Type-1 hypervisor independent of any high-level OS kernel, and runs in a higher CPU privilege level. It does not depend on any lower-privileged OS kernel/code for its core functionality. This increases its security and can support a much smaller trusted computing base than a Type-2 hypervisor. Gunyah is designed for isolated virtual machine use cases and to support launching trusted+isolated virtual machines from a relatively less trusted host virtual machine. Gunyah is an open source hypervisor. The source repo is available at https://github.com/quic/gunyah-hypervisor. The diagram below shows the architecture for AArch64. :: VM A VM B +-----+ +-----+ | +-----+ +-----+ +-----+ | | | | | | | | | | | EL0 | APP | | APP | | | APP | | APP | | APP | | | | | | | | | | | | +-----+ +-----+ | +-----+ +-----+ +-----+ ---------------------|------------------------- +--------------+ | +----------------------+ | | | | | EL1 | Linux Kernel | | |Linux kernel/Other OS | ... | | | | | +--------------+ | +----------------------+ --------hvc/smc------|------hvc/smc------------ +----------------------------------------+ | | EL2 | Gunyah Hypervisor | | | +----------------------------------------+ Gunyah provides these following features. - Threads and Scheduling: The scheduler schedules virtual CPUs (VCPUs) on physical CPUs and enables time-sharing of the CPUs. - Memory Management: Gunyah tracks memory ownership and use of all memory under its control. It provides low level dynamic memory management APIs on top of which higher level donation, lending and sharing is built. Gunyah provides strong VM memory isolation for trusted VMs. - Interrupt Virtualization: Interrupts are managed by the hypervisor and are routed directly to the assigned VM. - Inter-VM Communication: There are several different mechanisms provided for communicating between VMs. - Device Virtualization: Para-virtualization of devices is supported using inter-VM communication and virtio primitives. Low level architecture features and devices such as cpu timers, interrupt controllers are supported with hardware virtualization and emulation where required. - Resource Manager: Gunyah supports a "root" VM that initially owns all VM memory and IO resources. The Gunyah Resource Manager is the default bundled root VM and provides high-level services including dynamic VM management and secure memory donation, lending and sharing. This series adds the basic framework for detecting that Linux is running under Gunyah as a virtual machine, communication with the Gunyah Resource Manager, and a sample virtual machine manager capable of launching virtual machines. Changes in v17: - Replace RM's irq_chip with irq_create_fwspec_mapping - Unmap lent memory from kernel logical map - Small optimization to unlock folio earlier to allow vCPUs racing for the same folio to run sooner - Add missed "safe to lend" checks for a folio when constructing mem parcel Changes in v16: https://lore.kernel.org/r/20240109-gunyah-v16-0-634904bf4ce9@xxxxxxxxxxx - Fleshed out memory reclaim while VM is running - Documentation and comments Changes in v15: https://lore.kernel.org/r/20231215-gunyah-v15-0-192a5d872a30@xxxxxxxxxxx - First implementation of virtual machines backed by guestmemfd and using demand paging to provide memory instead of all up front. - Use message queue hypercalls directly instead of traversing through mailbox framework. Changes in v14: https://lore.kernel.org/all/20230613172054.3959700-1-quic_eberman@xxxxxxxxxxx/ - Coding/cosmetic tweaks suggested by Alex - Mark IRQs as wake-up capable Changes in v13: https://lore.kernel.org/all/20230509204801.2824351-1-quic_eberman@xxxxxxxxxxx/ - Tweaks to message queue driver to address race condition between IRQ and mailbox registration - Allow removal of VM functions by function-specific comparison -- specifically to allow removing irqfd by label only and not requiring original FD to be provided. Changes in v12: https://lore.kernel.org/all/20230424231558.70911-1-quic_eberman@xxxxxxxxxxx/ - Stylistic/cosmetic tweaks suggested by Alex - Remove patch "virt: gunyah: Identify hypervisor version" and squash the check that we're running under a reasonable Gunyah hypervisor into RM driver - Refactor platform hooks into a separate module per suggestion from Srini - GFP_KERNEL_ACCOUNT and account_locked_vm() for page pinning - enum-ify related constants Changes in v11: https://lore.kernel.org/all/20230304010632.2127470-1-quic_eberman@xxxxxxxxxxx/ - Rename struct gh_vm_dtb_config:gpa -> guest_phys_addr & overflow checks for this - More docstrings throughout - Make resp_buf and resp_buf_size optional - Replace deprecated idr with xarray - Refconting on misc device instead of RM's platform device - Renaming variables, structs, etc. from gunyah_ -> gh_ - Drop removal of user mem regions - Drop mem_lend functionality; to converge with restricted_memfd later Changes in v10: https://lore.kernel.org/all/20230214211229.3239350-1-quic_eberman@xxxxxxxxxxx/ - Fix bisectability (end result of series is same, --fixups applied to wrong commits) - Convert GH_ERROR_* and GH_RM_ERROR_* to enums - Correct race condition between allocating/freeing user memory - Replace offsetof with struct_size - Series-wide renaming of functions to be more consistent - VM shutdown & restart support added in vCPU and VM Manager patches - Convert VM function name (string) to type (number) - Convert VM function argument to value (which could be a pointer) to remove memory wastage for arguments - Remove defensive checks of hypervisor correctness - Clean ups to ioeventfd as suggested by Srivatsa Changes in v9: https://lore.kernel.org/all/20230120224627.4053418-1-quic_eberman@xxxxxxxxxxx/ - Refactor Gunyah API flags to be exposed as feature flags at kernel level - Move mbox client cleanup into gunyah_msgq_remove() - Simplify gh_rm_call return value and response payload - Missing clean-up/error handling/little endian fixes as suggested by Srivatsa and Alex in v8 series Changes in v8: https://lore.kernel.org/all/20221219225850.2397345-1-quic_eberman@xxxxxxxxxxx/ - Treat VM manager as a library of RM - Add patches 21-28 as RFC to support proxy-scheduled vCPUs and necessary bits to support virtio from Gunyah userspace Changes in v7: https://lore.kernel.org/all/20221121140009.2353512-1-quic_eberman@xxxxxxxxxxx/ - Refactor to remove gunyah RM bus - Refactor allow multiple RM device instances - Bump UAPI to start at 0x0 - Refactor QCOM SCM's platform hooks to allow CONFIG_QCOM_SCM=Y/CONFIG_GUNYAH=M combinations Changes in v6: https://lore.kernel.org/all/20221026185846.3983888-1-quic_eberman@xxxxxxxxxxx/ - *Replace gunyah-console with gunyah VM Manager* - Move include/asm-generic/gunyah.h into include/linux/gunyah.h - s/gunyah_msgq/gh_msgq/ - Minor tweaks and documentation tidying based on comments from Jiri, Greg, Arnd, Dmitry, and Bagas. Changes in v5 https://lore.kernel.org/all/20221011000840.289033-1-quic_eberman@xxxxxxxxxxx/ - Dropped sysfs nodes - Switch from aux bus to Gunyah RM bus for the subdevices - Cleaning up RM console Changes in v4: https://lore.kernel.org/all/20220928195633.2348848-1-quic_eberman@xxxxxxxxxxx/ - Tidied up documentation throughout based on questions/feedback received - Switched message queue implementation to use mailboxes - Renamed "gunyah_device" as "gunyah_resource" Changes in v3: https://lore.kernel.org/all/20220811214107.1074343-1-quic_eberman@xxxxxxxxxxx/ - /Maintained/Supported/ in MAINTAINERS - Tidied up documentation throughout based on questions/feedback received - Moved hypercalls into arch/arm64/gunyah/; following hyper-v's implementation - Drop opaque typedefs - Move sysfs nodes under /sys/hypervisor/gunyah/ - Moved Gunyah console driver to drivers/tty/ - Reworked gh_device design to drop the Gunyah bus. Changes in v2: https://lore.kernel.org/all/20220801211240.597859-1-quic_eberman@xxxxxxxxxxx/ - DT bindings clean up - Switch hypercalls to follow SMCCC v1: https://lore.kernel.org/all/20220223233729.1571114-1-quic_eberman@xxxxxxxxxxx/ Signed-off-by: Elliot Berman <quic_eberman@xxxxxxxxxxx> --- Elliot Berman (35): docs: gunyah: Introduce Gunyah Hypervisor dt-bindings: Add binding for gunyah hypervisor gunyah: Common types and error codes for Gunyah hypercalls virt: gunyah: Add hypercalls to identify Gunyah virt: gunyah: Add hypervisor driver virt: gunyah: msgq: Add hypercalls to send and receive messages gunyah: rsc_mgr: Add resource manager RPC core gunyah: vm_mgr: Introduce basic VM Manager gunyah: rsc_mgr: Add VM lifecycle RPC gunyah: vm_mgr: Add VM start/stop virt: gunyah: Translate gh_rm_hyp_resource into gunyah_resource virt: gunyah: Add resource tickets gunyah: vm_mgr: Add framework for VM Functions virt: gunyah: Add hypercalls for running a vCPU virt: gunyah: Add proxy-scheduled vCPUs gunyah: Add hypercalls for demand paging gunyah: rsc_mgr: Add memory parcel RPC mm/interval_tree: Export iter_first/iter_next arch/mm: Export direct {un,}map functions virt: gunyah: Add interfaces to map memory into guest address space gunyah: rsc_mgr: Add platform ops on mem_lend/mem_reclaim virt: gunyah: Add Qualcomm Gunyah platform ops virt: gunyah: Implement guestmemfd virt: gunyah: Add ioctl to bind guestmem to VMs virt: gunyah: guestmem: Initialize RM mem parcels from guestmem virt: gunyah: Share guest VM dtb configuration to Gunyah gunyah: rsc_mgr: Add RPC to enable demand paging virt: gunyah: Enable demand paging gunyah: rsc_mgr: Add RPC to set VM boot context virt: gunyah: Allow userspace to initialize context of primary vCPU virt: gunyah: Add hypercalls for sending doorbell virt: gunyah: Add irqfd interface virt: gunyah: Add IO handlers virt: gunyah: Add ioeventfd MAINTAINERS: Add Gunyah hypervisor drivers section .../bindings/firmware/gunyah-hypervisor.yaml | 82 ++ Documentation/userspace-api/ioctl/ioctl-number.rst | 1 + Documentation/virt/gunyah/index.rst | 135 +++ Documentation/virt/gunyah/message-queue.rst | 68 ++ Documentation/virt/index.rst | 1 + MAINTAINERS | 12 + arch/arm64/Kbuild | 1 + arch/arm64/gunyah/Makefile | 3 + arch/arm64/gunyah/gunyah_hypercall.c | 279 ++++++ arch/arm64/include/asm/gunyah.h | 57 ++ arch/arm64/mm/pageattr.c | 3 + drivers/virt/Kconfig | 2 + drivers/virt/Makefile | 1 + drivers/virt/gunyah/Kconfig | 47 + drivers/virt/gunyah/Makefile | 9 + drivers/virt/gunyah/guest_memfd.c | 987 ++++++++++++++++++++ drivers/virt/gunyah/gunyah.c | 52 ++ drivers/virt/gunyah/gunyah_ioeventfd.c | 139 +++ drivers/virt/gunyah/gunyah_irqfd.c | 187 ++++ drivers/virt/gunyah/gunyah_platform_hooks.c | 117 +++ drivers/virt/gunyah/gunyah_qcom.c | 220 +++++ drivers/virt/gunyah/gunyah_vcpu.c | 590 ++++++++++++ drivers/virt/gunyah/rsc_mgr.c | 836 +++++++++++++++++ drivers/virt/gunyah/rsc_mgr.h | 144 +++ drivers/virt/gunyah/rsc_mgr_rpc.c | 602 +++++++++++++ drivers/virt/gunyah/vm_mgr.c | 993 +++++++++++++++++++++ drivers/virt/gunyah/vm_mgr.h | 215 +++++ drivers/virt/gunyah/vm_mgr_mem.c | 356 ++++++++ include/linux/gunyah.h | 483 ++++++++++ include/uapi/linux/gunyah.h | 378 ++++++++ mm/interval_tree.c | 3 + 31 files changed, 7003 insertions(+) --- base-commit: ffd2cb6b718e189e7e2d5d0c19c25611f92e061a change-id: 20231208-gunyah-952aca7668e0 Best regards, -- Elliot Berman <quic_eberman@xxxxxxxxxxx>
