Commit fe85ce31 authored by Sean Christopherson's avatar Sean Christopherson
Browse files

KVM: selftests: Assert that vcpu_{g,s}et_reg() won't truncate 



Assert that the register being read/written by vcpu_{g,s}et_reg() is no
larger than a uint64_t, i.e. that a selftest isn't unintentionally
truncating the value being read/written.

Ideally, the assert would be done at compile-time, but that would limit
the checks to hardcoded accesses and/or require fancier compile-time
assertion infrastructure to filter out dynamic usage.

Reviewed-by: default avatarAndrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20241128005547.4077116-4-seanjc@google.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 09bb926d

tools/testing/selftests/kvm/include/kvm_util.h

+4 −0
Original line number Diff line number Diff line
@@ -707,6 +707,8 @@ static inline uint64_t vcpu_get_reg(struct kvm_vcpu *vcpu, uint64_t id) 
	uint64_t val;

	struct kvm_one_reg reg = { .id = id, .addr = (uint64_t)&val };



	TEST_ASSERT(KVM_REG_SIZE(id) <= sizeof(val), "Reg %lx too big", id);



	vcpu_ioctl(vcpu, KVM_GET_ONE_REG, &reg);

	return val;

}
@@ -714,6 +716,8 @@ static inline void vcpu_set_reg(struct kvm_vcpu *vcpu, uint64_t id, uint64_t val 
{

	struct kvm_one_reg reg = { .id = id, .addr = (uint64_t)&val };



	TEST_ASSERT(KVM_REG_SIZE(id) <= sizeof(val), "Reg %lx too big", id);



	vcpu_ioctl(vcpu, KVM_SET_ONE_REG, &reg);

}