Opcode* | Instruction | Op/En | 64/32bit Mode Support | CPUID Feature Flag | Description |
---|---|---|---|---|---|
NP 0F 01 EE | RDPKRU | ZO | V/V | OSPKE | Reads PKRU into EAX. |
Op/En | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
---|---|---|---|---|
ZO | N/A | N/A | N/A | N/A |
Reads the value of PKRU into EAX and clears EDX. ECX must be 0 when RDPKRU is executed; otherwise, a general-protection exception (#GP) occurs.
RDPKRU can be executed only if CR4.PKE = 1; otherwise, an invalid-opcode exception (#UD) occurs. Software can discover the value of CR4.PKE by examining CPUID.(EAX=07H,ECX=0H):ECX.OSPKE [bit 4].
On processors that support the Intel 64 Architecture, the high-order 32-bits of RCX are ignored and the high-order 32-bits of RDX and RAX are cleared.
IF (ECX = 0) THEN EAX := PKRU; EDX := 0; ELSE #GP(0); FI;
None.
RDPKRU uint32_t _rdpkru_u32(void);
#GP(0) | If ECX ≠ 0. |
#UD | If the LOCK prefix is used. |
If CR4.PKE = 0. |
Same exceptions as in protected mode.
Same exceptions as in protected mode.
Same exceptions as in protected mode.
Same exceptions as in protected mode.