linux-kernel - [PATCH v3 16/57] KVM: selftests: Fix a bad TEST

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Message-ID: <20241128013424.4096668-17-seanjc@google.com>
Date: Wed, 27 Nov 2024 17:33:43 -0800
From: Sean Christopherson <seanjc@...gle.com>
To: Paolo Bonzini <pbonzini@...hat.com>, Sean Christopherson <seanjc@...gle.com>, 
	Vitaly Kuznetsov <vkuznets@...hat.com>, Jarkko Sakkinen <jarkko@...nel.org>
Cc: kvm@...r.kernel.org, linux-sgx@...r.kernel.org, 
	linux-kernel@...r.kernel.org, Maxim Levitsky <mlevitsk@...hat.com>, 
	Hou Wenlong <houwenlong.hwl@...group.com>, Xiaoyao Li <xiaoyao.li@...el.com>, 
	Kechen Lu <kechenl@...dia.com>, Oliver Upton <oliver.upton@...ux.dev>, 
	Binbin Wu <binbin.wu@...ux.intel.com>, Yang Weijiang <weijiang.yang@...el.com>, 
	Robert Hoo <robert.hoo.linux@...il.com>
Subject: [PATCH v3 16/57] KVM: selftests: Fix a bad TEST_REQUIRE() in x86's
 KVM PV test

Actually check for KVM support for disabling HLT-exiting instead of
effectively checking that KVM_CAP_X86_DISABLE_EXITS is #defined to a
non-zero value, and convert the TEST_REQUIRE() to a simple return so
that only the sub-test is skipped if HLT-exiting is mandatory.

The goof has likely gone unnoticed because all x86 CPUs support disabling
HLT-exiting, only systems with the opt-in mitigate_smt_rsb KVM module
param disallow HLT-exiting.

Reviewed-by: Maxim Levitsky <mlevitsk@...hat.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 tools/testing/selftests/kvm/x86_64/kvm_pv_test.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86_64/kvm_pv_test.c b/tools/testing/selftests/kvm/x86_64/kvm_pv_test.c
index 78878b3a2725..2aee93108a54 100644
--- a/tools/testing/selftests/kvm/x86_64/kvm_pv_test.c
+++ b/tools/testing/selftests/kvm/x86_64/kvm_pv_test.c
@@ -140,10 +140,11 @@ static void test_pv_unhalt(void)
 	struct kvm_cpuid_entry2 *ent;
 	u32 kvm_sig_old;
 
+	if (!(kvm_check_cap(KVM_CAP_X86_DISABLE_EXITS) & KVM_X86_DISABLE_EXITS_HLT))
+		return;
+
 	pr_info("testing KVM_FEATURE_PV_UNHALT\n");
 
-	TEST_REQUIRE(KVM_CAP_X86_DISABLE_EXITS);
-
 	/* KVM_PV_UNHALT test */
 	vm = vm_create_with_one_vcpu(&vcpu, guest_main);
 	vcpu_set_cpuid_feature(vcpu, X86_FEATURE_KVM_PV_UNHALT);
-- 
2.47.0.338.g60cca15819-goog