linux-kernel - [kvm-unit-tests 2/7] x86/svm: Move CR0 selective write intercept test near CR3 intercept

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Message-ID: <20251024194925.3201933-3-yosry.ahmed@linux.dev>
Date: Fri, 24 Oct 2025 19:49:20 +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 <yosryahmed@...gle.com>
Subject: [kvm-unit-tests 2/7] x86/svm: Move CR0 selective write intercept test near CR3 intercept

From: Yosry Ahmed <yosryahmed@...gle.com>

It makes more semantic sense for these tests to be in close proximity.

Signed-off-by: Yosry Ahmed <yosryahmed@...gle.com>
---
 x86/svm_tests.c | 64 ++++++++++++++++++++++++-------------------------
 1 file changed, 32 insertions(+), 32 deletions(-)

diff --git a/x86/svm_tests.c b/x86/svm_tests.c
index e9116591..feeb27d6 100644
--- a/x86/svm_tests.c
+++ b/x86/svm_tests.c
@@ -112,6 +112,35 @@ static bool finished_rsm_intercept(struct svm_test *test)
 	return get_test_stage(test) == 2;
 }
 
+static void prepare_sel_cr0_intercept(struct svm_test *test)
+{
+	vmcb->save.cr0 &= ~X86_CR0_CD;
+	vmcb->control.intercept |= (1ULL << INTERCEPT_SELECTIVE_CR0);
+}
+
+static void test_sel_cr0_write_intercept(struct svm_test *test)
+{
+	unsigned long cr0;
+
+	/* read cr0, set CD, and write back */
+	cr0  = read_cr0();
+	cr0 |= X86_CR0_CD;
+	write_cr0(cr0);
+
+	/*
+	 * If we are here the test failed, not sure what to do now because we
+	 * are not in guest-mode anymore so we can't trigger an intercept.
+	 * Trigger a tripple-fault for now.
+	 */
+	report_fail("sel_cr0 test. Can not recover from this - exiting");
+	exit(report_summary());
+}
+
+static bool check_sel_cr0_intercept(struct svm_test *test)
+{
+	return vmcb->control.exit_code == SVM_EXIT_CR0_SEL_WRITE;
+}
+
 static void prepare_cr3_intercept(struct svm_test *test)
 {
 	default_prepare(test);
@@ -793,35 +822,6 @@ static bool check_asid_zero(struct svm_test *test)
 	return vmcb->control.exit_code == SVM_EXIT_ERR;
 }
 
-static void prepare_sel_cr0_intercept(struct svm_test *test)
-{
-	vmcb->save.cr0 &= ~X86_CR0_CD;
-	vmcb->control.intercept |= (1ULL << INTERCEPT_SELECTIVE_CR0);
-}
-
-static void test_sel_cr0_write_intercept(struct svm_test *test)
-{
-	unsigned long cr0;
-
-	/* read cr0, set CD, and write back */
-	cr0  = read_cr0();
-	cr0 |= X86_CR0_CD;
-	write_cr0(cr0);
-
-	/*
-	 * If we are here the test failed, not sure what to do now because we
-	 * are not in guest-mode anymore so we can't trigger an intercept.
-	 * Trigger a tripple-fault for now.
-	 */
-	report_fail("sel_cr0 test. Can not recover from this - exiting");
-	exit(report_summary());
-}
-
-static bool check_sel_cr0_intercept(struct svm_test *test)
-{
-	return vmcb->control.exit_code == SVM_EXIT_CR0_SEL_WRITE;
-}
-
 #define TSC_ADJUST_VALUE    (1ll << 32)
 #define TSC_OFFSET_VALUE    (~0ull << 48)
 static bool ok;
@@ -3458,6 +3458,9 @@ struct svm_test svm_tests[] = {
 	{ "rsm", default_supported,
 	  prepare_rsm_intercept, default_prepare_gif_clear,
 	  test_rsm_intercept, finished_rsm_intercept, check_rsm_intercept },
+	{ "sel cr0 write intercept", default_supported,
+	  prepare_sel_cr0_intercept, default_prepare_gif_clear,
+	  test_sel_cr0_write_intercept, default_finished, check_sel_cr0_intercept},
 	{ "cr3 read intercept", default_supported,
 	  prepare_cr3_intercept, default_prepare_gif_clear,
 	  test_cr3_intercept, default_finished, check_cr3_intercept },
@@ -3482,9 +3485,6 @@ struct svm_test svm_tests[] = {
 	{ "asid_zero", default_supported, prepare_asid_zero,
 	  default_prepare_gif_clear, test_asid_zero,
 	  default_finished, check_asid_zero },
-	{ "sel cr0 write intercept", default_supported,
-	  prepare_sel_cr0_intercept, default_prepare_gif_clear,
-	  test_sel_cr0_write_intercept, default_finished, check_sel_cr0_intercept},
 	{ "tsc_adjust", tsc_adjust_supported, tsc_adjust_prepare,
 	  default_prepare_gif_clear, tsc_adjust_test,
 	  default_finished, tsc_adjust_check },
-- 
2.51.1.821.gb6fe4d2222-goog