linux-kernel - [kvm-unit-tests 1/4] x86/vmx: Skip vmx_pf_exception_test

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Message-ID: <20251104193016.3408754-2-yosry.ahmed@linux.dev>
Date: Tue,  4 Nov 2025 19:30:13 +0000
From: Yosry Ahmed <yosry.ahmed@...ux.dev>
To: Sean Christopherson <seanjc@...gle.com>
Cc: Paolo Bonzini <pbonzini@...hat.com>,
	Jim Mattson <jmattson@...gle.com>,
	kvm@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Yosry Ahmed <yosry.ahmed@...ux.dev>
Subject: [kvm-unit-tests 1/4] x86/vmx: Skip vmx_pf_exception_test_fep early if FEP is not available

The check to skip the test is currently performed in the guest code.
There a few TEST_ASSERTs that happen before the guest is run, which
internally call report_passed(). The latter increases the number of
passed tests.

Hence, when vmx_pf_exception_test_fep is run, report_summary() does not
return a "skip" error code because the total number of tests is larger
than the number of skipped tests.

Skip early if FEP is not available, before any assertions, such that
report_summary() finds exactly 1 skipped test and returns the
appropriate error code.

Signed-off-by: Yosry Ahmed <yosry.ahmed@...ux.dev>
---
 x86/vmx_tests.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/x86/vmx_tests.c b/x86/vmx_tests.c
index 0b3cfe50c6142..4f214ebdbe1d9 100644
--- a/x86/vmx_tests.c
+++ b/x86/vmx_tests.c
@@ -10644,7 +10644,10 @@ static void vmx_pf_exception_test(void)

 static void vmx_pf_exception_forced_emulation_test(void)
 {
-	__vmx_pf_exception_test(NULL, NULL, vmx_pf_exception_forced_emulation_test_guest);
+	if (is_fep_available)
+		__vmx_pf_exception_test(NULL, NULL, vmx_pf_exception_forced_emulation_test_guest);
+	else
+		report_skip("Forced emulation prefix (FEP) not available\n");
 }

 static void invalidate_tlb_no_vpid(void *data)
-- 
2.51.2.1026.g39e6a42477-goog