Re: [PATCH v2 0/3] Introduce CONFIG_MSHV_ROOT for root partition code

From: Wei Liu
Date: Fri Feb 21 2025 - 21:32:15 EST


On Fri, Feb 21, 2025 at 11:56:32AM -0800, Nuno Das Neves wrote:
> Running in the root partition is a unique and specialized case that
> requires additional code. CONFIG_MSHV_ROOT allows Hyper-V guest kernels
> to exclude this code, which is important since significant additional code
> specific to the root partition is expected to be added over time.
>
> To do this, change hv_root_partition to be a function which is stubbed out
> to return false if CONFIG_MSHV_ROOT=n, and don't compile hv_proc.c at all,
> stubbing out those functions with inline versions.
>
> Store the partition type (guest or root) in an enum hv_curr_partition_type,
> which can be extended beyond just guest and root partition.
>
> While at it, introduce hv_result_to_errno() to convert Hyper-V status codes
> to regular linux errors. This is useful because the caller of a hypercall
> helper function (such as those in hv_proc.c) usually can't and doesn't
> interpret the Hyper-V status, so it is better to convert it to an error code
> and reduce the possibility of misinterpreting it. This also alows the stubbed
> versions of the hv_proc.c functions to just return a linux error code.
>
> Signed-off-by: Nuno Das Neves <nunodasneves@xxxxxxxxxxxxxxxxxxx>

No need to sign this off. :-)

>
> Nuno Das Neves (3):
> hyperv: Convert hypercall statuses to linux error codes
> hyperv: Change hv_root_partition into a function
> hyperv: Add CONFIG_MSHV_ROOT to gate root partition support
>

Applied to hyperv-next. Thanks.