[PATCH 40/42] KVM: selftests: Clean up requirements for XFD-aware XSAVE features

[Sean Christopherson]

Provide informative error messages for the various checks related to
requesting access to XSAVE features that are buried behind XSAVE Feature
Disabling (XFD).

Opportunistically rename the helper to have "require" in the name so that
it's somewhat obvious that the helper may skip the test.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 tools/testing/selftests/kvm/include/x86_64/processor.h | 5 ++++-
 tools/testing/selftests/kvm/lib/x86_64/processor.c     | 8 +++++---
 tools/testing/selftests/kvm/x86_64/amx_test.c          | 2 +-
 3 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index e97b7c4ce367..3fd3d58148c2 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -758,7 +758,10 @@ void vm_set_page_table_entry(struct kvm_vm *vm, struct kvm_vcpu *vcpu,
 uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
 		       uint64_t a3);
 
-void vm_xsave_req_perm(int bit);
+void __vm_xsave_require_permission(int bit, const char *name);
+
+#define vm_xsave_require_permission(perm)	\
+	__vm_xsave_require_permission(perm, #perm)
 
 enum x86_page_size {
 	X86_PAGE_SIZE_4K = 0,
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 86e610967e79..6e8c8781996c 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -579,7 +579,7 @@ static void vcpu_setup(struct kvm_vm *vm, struct kvm_vcpu *vcpu)
 	vcpu_sregs_set(vcpu, &sregs);
 }
 
-void vm_xsave_req_perm(int bit)
+void __vm_xsave_require_permission(int bit, const char *name)
 {
 	int kvm_fd;
 	u64 bitmask;
@@ -597,10 +597,12 @@ void vm_xsave_req_perm(int bit)
 	close(kvm_fd);
 
 	if (rc == -1 && (errno == ENXIO || errno == EINVAL))
-		exit(KSFT_SKIP);
+		__TEST_REQUIRE(0, "KVM_X86_XCOMP_GUEST_SUPP not supported");
+
 	TEST_ASSERT(rc == 0, "KVM_GET_DEVICE_ATTR(0, KVM_X86_XCOMP_GUEST_SUPP) error: %ld", rc);
 
-	TEST_REQUIRE(bitmask & (1ULL << bit));
+	__TEST_REQUIRE(bitmask & (1ULL << bit),
+		       "Required XSAVE feature '%s' not supported", name);
 
 	TEST_REQUIRE(!syscall(SYS_arch_prctl, ARCH_REQ_XCOMP_GUEST_PERM, bit));
 
diff --git a/tools/testing/selftests/kvm/x86_64/amx_test.c b/tools/testing/selftests/kvm/x86_64/amx_test.c
index 411a33cd4296..5d749eae8c45 100644
--- a/tools/testing/selftests/kvm/x86_64/amx_test.c
+++ b/tools/testing/selftests/kvm/x86_64/amx_test.c
@@ -307,7 +307,7 @@ int main(int argc, char *argv[])
 	u32 amx_offset;
 	int stage, ret;
 
-	vm_xsave_req_perm(XSTATE_XTILE_DATA_BIT);
+	vm_xsave_require_permission(XSTATE_XTILE_DATA_BIT);
 
 	/* Create VM */
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
-- 
2.36.1.255.ge46751e96f-goog