hyperv: Do not overlap the hvcall IO areas in hv_vtl_apicid_to_vp_id()

The Top-Level Functional Specification for Hyper-V, Section 3.6 [1, 2],
disallows overlapping of the input and output hypercall areas, and
hv_vtl_apicid_to_vp_id() overlaps them.

Use the output hypercall page of the current vCPU for the hypercall.

[1] https://learn.microsoft.com/en-us/virtualization/hyper-v-on-windows/tlfs/hypercall-interface
[2] https://github.com/MicrosoftDocs/Virtualization-Documentation/tree/main/tlfs



Reported-by: Michael Kelley <mhklinux@outlook.com>
Closes: https://lore.kernel.org/lkml/SN6PR02MB4157B98CD34781CC87A9D921D40D2@SN6PR02MB4157.namprd02.prod.outlook.com/


Signed-off-by: Roman Kisel <romank@linux.microsoft.com>
Reviewed-by: Easwar Hariharan <eahariha@linux.microsoft.com>
Reviewed-by: Nuno Das Neves <nunodasneves@linux.microsoft.com>
Link: https://lore.kernel.org/r/20250108222138.1623703-6-romank@linux.microsoft.com


Signed-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20250108222138.1623703-6-romank@linux.microsoft.com>