Re: [PATCH v10 2/2] Drivers: hv: Introduce mshv_vtl driver

Naman Jain
2025-11-06T17:03:17Z

On 11/6/2025 8:24 PM, Michael Kelley wrote:
> From: Naman Jain <namjain@linux.microsoft.com> Sent: Tuesday, October 28, 2025 10:02 PM
>>
>> Provide an interface for Virtual Machine Monitor like OpenVMM and its
>> use as OpenHCL paravisor to control VTL0 (Virtual trust Level).
>> Expose devices and support IOCTLs for features like VTL creation,
>> VTL0 memory management, context switch, making hypercalls,
>> mapping VTL0 address space to VTL2 userspace, getting new VMBus
>> messages and channel events in VTL2 etc.
>>
>> Co-developed-by: Roman Kisel <romank@linux.microsoft.com>
>> Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
>> Co-developed-by: Saurabh Sengar <ssengar@linux.microsoft.com>
>> Signed-off-by: Saurabh Sengar <ssengar@linux.microsoft.com>
>> Signed-off-by: Naman Jain <namjain@linux.microsoft.com>
>> ---
>> arch/x86/hyperv/Makefile | 10 +-
>> arch/x86/hyperv/hv_vtl.c | 43 +
>> arch/x86/hyperv/mshv-asm-offsets.c | 37 +
>> arch/x86/hyperv/mshv_vtl_asm.S | 98 ++
>> arch/x86/include/asm/mshyperv.h | 34 +
>> drivers/hv/Kconfig | 26 +-
>> drivers/hv/Makefile | 7 +-
>> drivers/hv/mshv_vtl.h | 25 +
>> drivers/hv/mshv_vtl_main.c | 1392 ++++++++++++++++++++++++++++
>> include/hyperv/hvgdk_mini.h | 106 +++
>> include/uapi/linux/mshv.h | 80 ++
>> 11 files changed, 1855 insertions(+), 3 deletions(-)
>> create mode 100644 arch/x86/hyperv/mshv-asm-offsets.c
>> create mode 100644 arch/x86/hyperv/mshv_vtl_asm.S
>> create mode 100644 drivers/hv/mshv_vtl.h
>> create mode 100644 drivers/hv/mshv_vtl_main.c
>>
>
> I've reviewed and made suggestions on most of this code pretty
> carefully over the past few months and through 10 revisions. This
> version addresses my suggestions and looks good to me. There
> are a few areas, such as the assembly code in mshv_vtl_asm.S and
> the details of the hypervisor ABI for doing VTL Return, that are
> outside my area of expertise so I'm limited to a surface level
> review.
>
> Reviewed-by: Michael Kelley <mhklinux@outlook.com>

Thanks for the review Michael.

Regards
Naman