Commit b5e66df3 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: selftests: Add helpers for safe and safe+forced RDMSR, RDPMC, and XGETBV 



Add helpers for safe and safe-with-forced-emulations versions of RDMSR,
RDPMC, and XGETBV.  Use macro shenanigans to eliminate the rather large
amount of boilerplate needed to get values in and out of registers.

Tested-by: default avatarDapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20240109230250.424295-29-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent ab3b6a7d

tools/testing/selftests/kvm/include/x86_64/processor.h

+26 −12
Original line number Diff line number Diff line
@@ -1216,20 +1216,34 @@ void vm_install_exception_handler(struct kvm_vm *vm, int vector, 
	vector;								\

})



static inline uint8_t rdmsr_safe(uint32_t msr, uint64_t *val)

{

	uint64_t error_code;

	uint8_t vector;

	uint32_t a, d;

#define BUILD_READ_U64_SAFE_HELPER(insn, _fep, _FEP)			\

static inline uint8_t insn##_safe ##_fep(uint32_t idx, uint64_t *val)	\

{									\

	uint64_t error_code;						\

	uint8_t vector;							\

	uint32_t a, d;							\

									\

	asm volatile(KVM_ASM_SAFE##_FEP(#insn)				\

		     : "=a"(a), "=d"(d),				\

		       KVM_ASM_SAFE_OUTPUTS(vector, error_code)		\

		     : "c"(idx)						\

		     : KVM_ASM_SAFE_CLOBBERS);				\

									\

	*val = (uint64_t)a | ((uint64_t)d << 32);			\

	return vector;							\

}



	asm volatile(KVM_ASM_SAFE("rdmsr")

		     : "=a"(a), "=d"(d), KVM_ASM_SAFE_OUTPUTS(vector, error_code)

		     : "c"(msr)

		     : KVM_ASM_SAFE_CLOBBERS);

/*

 * Generate {insn}_safe() and {insn}_safe_fep() helpers for instructions that

 * use ECX as in input index, and EDX:EAX as a 64-bit output.

 */

#define BUILD_READ_U64_SAFE_HELPERS(insn)				\

	BUILD_READ_U64_SAFE_HELPER(insn, , )				\

	BUILD_READ_U64_SAFE_HELPER(insn, _fep, _FEP)			\



	*val = (uint64_t)a | ((uint64_t)d << 32);

	return vector;

}

BUILD_READ_U64_SAFE_HELPERS(rdmsr)

BUILD_READ_U64_SAFE_HELPERS(rdpmc)

BUILD_READ_U64_SAFE_HELPERS(xgetbv)



static inline uint8_t wrmsr_safe(uint32_t msr, uint64_t val)

{