This patch series introduces support for Virtual Trust Level (VTL) in Hyper-V systems. It provide a foundation for the implementation of Hyper-V VSM support in the Linux kernel, providing a secure platform for the development and deployment of applications. Virtual Secure Mode (VSM) is a critical aspect of the security infrastructure in Hyper-V systems. It provides a set of hypervisor capabilities and enlightenments that enable the creation and management of new security boundaries within operating system software. The VSM achieves and maintains isolation through Virtual Trust Levels, which are hierarchical, with higher levels being more privileged than lower levels. Please refer to this link for further information: https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/vsm This patch series adds the initialization of the x86 platform for VTL systems. This also adds the VTL early bootup code for initializing and bringing up secondary cpus to targeted VTL context. In VTL, AP has to start directly in the 64-bit mode, bypassing the usual 16-bit -> 32-bit -> 64-bit mode transition sequence that occurs after waking up an AP with SIPI whose vector points to the 16-bit AP startup trampoline code. Currently only VTL level supprted is '2'. This patch series is tested extensively on VTL2 systems. [V2] - Remove the code for reserve 1 IRQ. - boot_cpu_has -> cpu_feature_enabled. - Improved commit message for 0002 patch. - Improved Kconfig flag description for HYPERV_VTL. - Removed hv_result as a wrapper around hv_do_hypercall(). - The value of output[0] copied to a local variable before returning. Saurabh Sengar (2): x86/init: Make get/set_rtc_noop() public x86/hyperv: VTL support for Hyper-V arch/x86/Kconfig | 24 +++ arch/x86/hyperv/Makefile | 1 + arch/x86/hyperv/hv_vtl.c | 227 +++++++++++++++++++++++++++++ arch/x86/include/asm/hyperv-tlfs.h | 75 ++++++++++ arch/x86/include/asm/mshyperv.h | 14 ++ arch/x86/include/asm/x86_init.h | 2 + arch/x86/kernel/cpu/mshyperv.c | 6 +- arch/x86/kernel/x86_init.c | 4 +- include/asm-generic/hyperv-tlfs.h | 4 + 9 files changed, 350 insertions(+), 7 deletions(-) create mode 100644 arch/x86/hyperv/hv_vtl.c -- 2.34.1
