Commit af788f35 authored by Tianyu Lan's avatar Tianyu Lan Committed by Wei Liu
Browse files

x86/hyperv: Initialize shared memory boundary in the Isolation VM. 



Hyper-V exposes shared memory boundary via cpuid
HYPERV_CPUID_ISOLATION_CONFIG and store it in the
shared_gpa_boundary of ms_hyperv struct. This prepares
to share memory with host for SNP guest.

Reviewed-by: default avatarMichael Kelley <mikelley@microsoft.com>
Signed-off-by: default avatarTianyu Lan <Tianyu.Lan@microsoft.com>
Link: https://lore.kernel.org/r/20211025122116.264793-3-ltykernel@gmail.com


Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
parent 0cc4f6d9

arch/x86/kernel/cpu/mshyperv.c

+2 −0
Original line number Diff line number Diff line
@@ -313,6 +313,8 @@ static void __init ms_hyperv_init_platform(void) 
	if (ms_hyperv.priv_high & HV_ISOLATION) {

		ms_hyperv.isolation_config_a = cpuid_eax(HYPERV_CPUID_ISOLATION_CONFIG);

		ms_hyperv.isolation_config_b = cpuid_ebx(HYPERV_CPUID_ISOLATION_CONFIG);

		ms_hyperv.shared_gpa_boundary =

			BIT_ULL(ms_hyperv.shared_gpa_boundary_bits);



		pr_info("Hyper-V: Isolation Config: Group A 0x%x, Group B 0x%x\n",

			ms_hyperv.isolation_config_a, ms_hyperv.isolation_config_b);

include/asm-generic/mshyperv.h

+11 −1
Original line number Diff line number Diff line
@@ -35,7 +35,17 @@ struct ms_hyperv_info { 
	u32 max_vp_index;

	u32 max_lp_index;

	u32 isolation_config_a;

	union {

		u32 isolation_config_b;

		struct {

			u32 cvm_type : 4;

			u32 reserved1 : 1;

			u32 shared_gpa_boundary_active : 1;

			u32 shared_gpa_boundary_bits : 6;

			u32 reserved2 : 20;

		};

	};

	u64 shared_gpa_boundary;

};

extern struct ms_hyperv_info ms_hyperv;