Re: [PATCH hyperv-next v5 06/11] arm64, x86: hyperv: Report the VTL the system boots in

Wei Liu
2025-03-10T00:31:06Z

On Fri, Mar 07, 2025 at 02:02:58PM -0800, Roman Kisel wrote:
> The hyperv guest code might run in various Virtual Trust Levels.
>
> Report the level when the kernel boots in the non-default (0)
> one.
>
> Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
> ---
> arch/arm64/hyperv/mshyperv.c | 2 ++
> arch/x86/hyperv/hv_vtl.c | 2 +-
> 2 files changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/hyperv/mshyperv.c b/arch/arm64/hyperv/mshyperv.c
> index a7db03f5413d..3bc16dbee758 100644
> --- a/arch/arm64/hyperv/mshyperv.c
> +++ b/arch/arm64/hyperv/mshyperv.c
> @@ -108,6 +108,8 @@ static int __init hyperv_init(void)
> if (ms_hyperv.priv_high & HV_ACCESS_PARTITION_ID)
> hv_get_partition_id();
> ms_hyperv.vtl = get_vtl();
> + if (ms_hyperv.vtl > 0) /* non default VTL */

"non-default".

> + pr_info("Linux runs in Hyper-V Virtual Trust Level %d\n", ms_hyperv.vtl);
>
> ms_hyperv_late_init();
>
> diff --git a/arch/x86/hyperv/hv_vtl.c b/arch/x86/hyperv/hv_vtl.c
> index 4e1b1e3b5658..c21bee7e8ff3 100644
> --- a/arch/x86/hyperv/hv_vtl.c
> +++ b/arch/x86/hyperv/hv_vtl.c
> @@ -24,7 +24,7 @@ static bool __init hv_vtl_msi_ext_dest_id(void)
>
> void __init hv_vtl_init_platform(void)
> {
> - pr_info("Linux runs in Hyper-V Virtual Trust Level\n");
> + pr_info("Linux runs in Hyper-V Virtual Trust Level %d\n", ms_hyperv.vtl);

Where isn't there a check for ms_hyperv.vtl > 0 here?

Please be consistent across different architectures.

>
> x86_platform.realmode_reserve = x86_init_noop;
> x86_platform.realmode_init = x86_init_noop;
> --
> 2.43.0
>
>