__rmpupdate

Microsoft Specific

Writes a new reverse map table (RMP) entry.

Syntax

typedef struct rmp_entry {
   unsigned __int64 guest_pa;
   unsigned __int8 assigned;
   unsigned __int8 page_size : 1;
   unsigned __int8 rmp_2mb_region_status : 1;
   unsigned __int8 reserved1 : 6;
   unsigned __int8 immutable;
   unsigned __int8 reserved2;
   unsigned __int32 asid;
} rmp_entry;

unsigned int __rmpupdate(
   unsigned __int64 system_pa,
   rmp_entry *rmp_entry_state
);

Parameters

system_pa
[in] The system physical address.

rmp_entry_state
[in] The new RMP entry state.

Return value

Returns a status code that indicates the result of the operation.

Value	Description
0	The operation completed successfully.
1	An input parameter is invalid.
2	The current address space identifier (ASID) isn't zero, or the RMP entry is immutable.
3	Another processor is modifying the same RMP entry.
4	Overlapping 4-KB and 2-MB RMP entries were detected.

Remarks

The __rmpupdate intrinsic corresponds to the AMD RMPUPDATE machine instruction. A hypervisor can use it to change the RMP state of pages directly. It's available only as an intrinsic and can be used only in kernel mode.

For more information, see AMD64 Architecture Programmer's Manual, Volume 2: System Programming.

Requirements

Available starting with MSVC 19.52.3683

Intrinsic	Architecture	Header
__rmpupdate	AMD x86/x64 with SEV-SNP support	<ammintrin.h>

END Microsoft Specific

See also

Compiler intrinsics
__psmash
__pvalidate
__rmpadjust
__rmpquery
__rmpread