Re: [PATCH v5 10/10] Drivers: hv: Introduce mshv_root module to expose /dev/mshv to VMMs

Easwar Hariharan
2025-02-27T04:59:58Z

On 2/26/2025 3:08 PM, Nuno Das Neves wrote:
> Provide a set of IOCTLs for creating and managing child partitions when
> running as root partition on Hyper-V. The new driver is enabled via
> CONFIG_MSHV_ROOT.
>
> A brief overview of the interface:
>
> MSHV_CREATE_PARTITION is the entry point, returning a file descriptor
> representing a child partition. IOCTLs on this fd can be used to map
> memory, create VPs, etc.
>
> Creating a VP returns another file descriptor representing that VP which
> in turn has another set of corresponding IOCTLs for running the VP,
> getting/setting state, etc.
>
> MSHV_ROOT_HVCALL is a generic "passthrough" hypercall IOCTL which can be
> used for a number of partition or VP hypercalls. This is for hypercalls
> that do not affect any state in the kernel driver, such as getting and
> setting VP registers and partition properties, translating addresses,
> etc. It is "passthrough" because the binary input and output for the
> hypercall is only interpreted by the VMM - the kernel driver does
> nothing but insert the VP and partition id where necessary (which are
> always in the same place), and execute the hypercall.
>
> Co-developed-by: Wei Liu <wei.liu@kernel.org>
> Signed-off-by: Wei Liu <wei.liu@kernel.org>
> Co-developed-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> Signed-off-by: Stanislav Kinsburskii <skinsburskii@linux.microsoft.com>
> Co-developed-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
> Co-developed-by: Mukesh Rathor <mrathor@linux.microsoft.com>
> Signed-off-by: Mukesh Rathor <mrathor@linux.microsoft.com>
> Co-developed-by: Jinank Jain <jinankjain@microsoft.com>
> Signed-off-by: Jinank Jain <jinankjain@microsoft.com>
> Co-developed-by: Muminul Islam <muislam@microsoft.com>
> Signed-off-by: Muminul Islam <muislam@microsoft.com>
> Co-developed-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com>
> Signed-off-by: Anirudh Rayabharam <anrayabh@linux.microsoft.com>
> Signed-off-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
> ---

I see some issues reported by checkpatch, both vanilla and --strict.
<snip>

Thanks,
Easwar (he/him)