Commit 08e9d120 authored by Dexuan Cui's avatar Dexuan Cui Committed by Wei Liu
Browse files

x86/hyperv: Add hv_isolation_type_tdx() to detect TDX guests 



No logic change to SNP/VBS guests.

hv_isolation_type_tdx() will be used to instruct a TDX guest on Hyper-V to
do some TDX-specific operations, e.g. for a fully enlightened TDX guest
(i.e. without the paravisor), hv_do_hypercall() should use
__tdx_hypercall() and such a guest on Hyper-V should handle the Hyper-V
Event/Message/Monitor pages specially.

Reviewed-by: default avatarMichael Kelley <mikelley@microsoft.com>
Reviewed-by: default avatarTianyu Lan <tiala@microsoft.com>
Signed-off-by: default avatarDexuan Cui <decui@microsoft.com>
Signed-off-by: default avatarWei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20230824080712.30327-2-decui@microsoft.com
parent 86e619c9

arch/x86/hyperv/ivm.c

+9 −0
Original line number Diff line number Diff line
@@ -562,3 +562,12 @@ bool hv_isolation_type_en_snp(void) 
	return static_branch_unlikely(&isolation_type_en_snp);

}



DEFINE_STATIC_KEY_FALSE(isolation_type_tdx);

/*

 * hv_isolation_type_tdx - Check if the system runs in an Intel TDX based

 * isolated VM.

 */

bool hv_isolation_type_tdx(void)

{

	return static_branch_unlikely(&isolation_type_tdx);

}

arch/x86/include/asm/hyperv-tlfs.h

+2 −1
Original line number Diff line number Diff line
@@ -169,7 +169,8 @@ 
enum hv_isolation_type {

	HV_ISOLATION_TYPE_NONE	= 0,

	HV_ISOLATION_TYPE_VBS	= 1,

	HV_ISOLATION_TYPE_SNP	= 2

	HV_ISOLATION_TYPE_SNP	= 2,

	HV_ISOLATION_TYPE_TDX	= 3

};



/* Hyper-V specific model specific registers (MSRs) */

arch/x86/include/asm/mshyperv.h

+3 −0
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ union hv_ghcb; 


DECLARE_STATIC_KEY_FALSE(isolation_type_snp);

DECLARE_STATIC_KEY_FALSE(isolation_type_en_snp);

DECLARE_STATIC_KEY_FALSE(isolation_type_tdx);



typedef int (*hyperv_fill_flush_list_func)(

		struct hv_guest_mapping_flush_list *flush,
@@ -49,6 +50,8 @@ extern u64 hv_current_partition_id; 
extern union hv_ghcb * __percpu *hv_ghcb_pg;



extern bool hv_isolation_type_en_snp(void);

bool hv_isolation_type_tdx(void);



/*

 * DEFAULT INIT GPAT and SEGMENT LIMIT value in struct VMSA

 * to start AP in enlightened SEV guest.

arch/x86/kernel/cpu/mshyperv.c

+2 −0
Original line number Diff line number Diff line
@@ -418,6 +418,8 @@ static void __init ms_hyperv_init_platform(void) 
				static_branch_enable(&isolation_type_snp);

			else

				static_branch_enable(&isolation_type_en_snp);

		} else if (hv_get_isolation_type() == HV_ISOLATION_TYPE_TDX) {

			static_branch_enable(&isolation_type_tdx);

		}

	}

drivers/hv/hv_common.c

+6 −0
Original line number Diff line number Diff line
@@ -521,6 +521,12 @@ bool __weak hv_isolation_type_en_snp(void) 
}

EXPORT_SYMBOL_GPL(hv_isolation_type_en_snp);



bool __weak hv_isolation_type_tdx(void)

{

	return false;

}

EXPORT_SYMBOL_GPL(hv_isolation_type_tdx);



void __weak hv_setup_vmbus_handler(void (*handler)(void))

{

}