[V4 PATCH 0/3] Minor improvements to the selftest setup logic

[V4 PATCH 0/3] Minor improvements to the selftest setup logic

[Vishal Annapurve]

This series is posted in context of the discussion at:
https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com/

Major changes:
1) Move common startup logic to a single function in kvm_util.c
2) Introduce following APIs:
	kvm_selftest_arch_init: to perform arch specific common startup.
	kvm_arch_vm_post_create: to perform arch specific common setup
		after VM creation.

Changelog
=========
v4:
* Removed the patch to precompute cpu type, will be introduced as part of
  a separate series in future.
v3:
* Original series is split into two and this v3 version contains the
  improvements to selftest and VM setup.
  * Planning to upload the second series to execute hypercall
    instruction according to cpu type separately.
* Addressed comments from David and Sean.
link to v3:
https://lore.kernel.org/lkml/20221013121319.994170-1-vannapurve@google.com/
v2:
* Addressed comments from Andrew and David
  * Common function with constructor attribute used to setup initial state
  * Changes are split in more logical granules as per feedback
link to v2:
https://lore.kernel.org/all/20220915000448.1674802-1-vannapurve@google.com/

Vishal Annapurve (3):
  KVM: selftests: move common startup logic to kvm_util.c
  KVM: selftests: Add arch specific initialization
  KVM: selftests: Add arch specific post vm creation hook

 .../selftests/kvm/aarch64/arch_timer.c        |  3 ---
 .../selftests/kvm/aarch64/hypercalls.c        |  2 --
 .../testing/selftests/kvm/aarch64/vgic_irq.c  |  3 ---
 .../selftests/kvm/include/kvm_util_base.h     |  9 ++++++++
 .../selftests/kvm/lib/aarch64/processor.c     | 18 ++++++++--------
 tools/testing/selftests/kvm/lib/kvm_util.c    | 21 ++++++++++++++++---
 .../selftests/kvm/lib/x86_64/processor.c      |  6 ++++++
 .../testing/selftests/kvm/memslot_perf_test.c |  3 ---
 tools/testing/selftests/kvm/rseq_test.c       |  3 ---
 tools/testing/selftests/kvm/s390x/memop.c     |  2 --
 tools/testing/selftests/kvm/s390x/resets.c    |  2 --
 .../selftests/kvm/s390x/sync_regs_test.c      |  3 ---
 .../selftests/kvm/set_memory_region_test.c    |  3 ---
 .../kvm/x86_64/cr4_cpuid_sync_test.c          |  3 ---
 .../kvm/x86_64/emulator_error_test.c          |  3 ---
 .../selftests/kvm/x86_64/hyperv_cpuid.c       |  3 ---
 .../selftests/kvm/x86_64/platform_info_test.c |  3 ---
 .../kvm/x86_64/pmu_event_filter_test.c        |  3 ---
 .../selftests/kvm/x86_64/set_sregs_test.c     |  3 ---
 .../kvm/x86_64/svm_nested_soft_inject_test.c  |  3 ---
 .../selftests/kvm/x86_64/sync_regs_test.c     |  3 ---
 .../selftests/kvm/x86_64/userspace_io_test.c  |  3 ---
 .../kvm/x86_64/userspace_msr_exit_test.c      |  3 ---
 23 files changed, 42 insertions(+), 66 deletions(-)

-- 
2.38.1.431.g37b22c650d-goog

[V4 PATCH 1/3] KVM: selftests: move common startup logic to kvm_util.c

[Vishal Annapurve]

Consolidate common startup logic in one place by implementing a single
setup function with __attribute((constructor)) for all selftests within
kvm_util.c.

This allows moving logic like:
        /* Tell stdout not to buffer its content */
        setbuf(stdout, NULL);
to a single file for all selftests.

This will also allow any required setup at entry in future to be done in
common main function.

More context is discussed at:
https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com/

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
 tools/testing/selftests/kvm/aarch64/arch_timer.c            | 3 ---
 tools/testing/selftests/kvm/aarch64/hypercalls.c            | 2 --
 tools/testing/selftests/kvm/aarch64/vgic_irq.c              | 3 ---
 tools/testing/selftests/kvm/lib/kvm_util.c                  | 6 ++++++
 tools/testing/selftests/kvm/memslot_perf_test.c             | 3 ---
 tools/testing/selftests/kvm/rseq_test.c                     | 3 ---
 tools/testing/selftests/kvm/s390x/memop.c                   | 2 --
 tools/testing/selftests/kvm/s390x/resets.c                  | 2 --
 tools/testing/selftests/kvm/s390x/sync_regs_test.c          | 3 ---
 tools/testing/selftests/kvm/set_memory_region_test.c        | 3 ---
 tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c    | 3 ---
 tools/testing/selftests/kvm/x86_64/emulator_error_test.c    | 3 ---
 tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c           | 3 ---
 tools/testing/selftests/kvm/x86_64/platform_info_test.c     | 3 ---
 tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c  | 3 ---
 tools/testing/selftests/kvm/x86_64/set_sregs_test.c         | 3 ---
 .../selftests/kvm/x86_64/svm_nested_soft_inject_test.c      | 3 ---
 tools/testing/selftests/kvm/x86_64/sync_regs_test.c         | 3 ---
 tools/testing/selftests/kvm/x86_64/userspace_io_test.c      | 3 ---
 .../testing/selftests/kvm/x86_64/userspace_msr_exit_test.c  | 3 ---
 20 files changed, 6 insertions(+), 54 deletions(-)

diff --git a/tools/testing/selftests/kvm/aarch64/arch_timer.c b/tools/testing/selftests/kvm/aarch64/arch_timer.c
index 574eb73f0e90..07836bd2672b 100644
--- a/tools/testing/selftests/kvm/aarch64/arch_timer.c
+++ b/tools/testing/selftests/kvm/aarch64/arch_timer.c
@@ -462,9 +462,6 @@ int main(int argc, char *argv[])
 {
 	struct kvm_vm *vm;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	if (!parse_args(argc, argv))
 		exit(KSFT_SKIP);
 
diff --git a/tools/testing/selftests/kvm/aarch64/hypercalls.c b/tools/testing/selftests/kvm/aarch64/hypercalls.c
index a39da3fe4952..6463fd118429 100644
--- a/tools/testing/selftests/kvm/aarch64/hypercalls.c
+++ b/tools/testing/selftests/kvm/aarch64/hypercalls.c
@@ -306,8 +306,6 @@ static void test_run(void)
 
 int main(void)
 {
-	setbuf(stdout, NULL);
-
 	test_run();
 	return 0;
 }
diff --git a/tools/testing/selftests/kvm/aarch64/vgic_irq.c b/tools/testing/selftests/kvm/aarch64/vgic_irq.c
index 17417220a083..3f204f2e93bf 100644
--- a/tools/testing/selftests/kvm/aarch64/vgic_irq.c
+++ b/tools/testing/selftests/kvm/aarch64/vgic_irq.c
@@ -818,9 +818,6 @@ int main(int argc, char **argv)
 	int opt;
 	bool eoi_split = false;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	while ((opt = getopt(argc, argv, "hn:e:l:")) != -1) {
 		switch (opt) {
 		case 'n':
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index f1cb1627161f..37d7d144c74e 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -2021,3 +2021,9 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 		break;
 	}
 }
+
+void __attribute((constructor)) kvm_selftest_init(void)
+{
+	/* Tell stdout not to buffer its content. */
+	setbuf(stdout, NULL);
+}
diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
index 44995446d942..f7ba77ff45c9 100644
--- a/tools/testing/selftests/kvm/memslot_perf_test.c
+++ b/tools/testing/selftests/kvm/memslot_perf_test.c
@@ -1007,9 +1007,6 @@ int main(int argc, char *argv[])
 	struct test_result rbestslottime;
 	int tctr;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	if (!parse_args(argc, argv, &targs))
 		return -1;
 
diff --git a/tools/testing/selftests/kvm/rseq_test.c b/tools/testing/selftests/kvm/rseq_test.c
index 6f88da7e60be..18297b803159 100644
--- a/tools/testing/selftests/kvm/rseq_test.c
+++ b/tools/testing/selftests/kvm/rseq_test.c
@@ -205,9 +205,6 @@ int main(int argc, char *argv[])
 	struct kvm_vcpu *vcpu;
 	u32 cpu, rseq_cpu;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	r = sched_getaffinity(0, sizeof(possible_mask), &possible_mask);
 	TEST_ASSERT(!r, "sched_getaffinity failed, errno = %d (%s)", errno,
 		    strerror(errno));
diff --git a/tools/testing/selftests/kvm/s390x/memop.c b/tools/testing/selftests/kvm/s390x/memop.c
index 9113696d5178..3fd81e58f40c 100644
--- a/tools/testing/selftests/kvm/s390x/memop.c
+++ b/tools/testing/selftests/kvm/s390x/memop.c
@@ -760,8 +760,6 @@ int main(int argc, char *argv[])
 
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_S390_MEM_OP));
 
-	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
-
 	ksft_print_header();
 
 	ksft_set_plan(ARRAY_SIZE(testlist));
diff --git a/tools/testing/selftests/kvm/s390x/resets.c b/tools/testing/selftests/kvm/s390x/resets.c
index 19486084eb30..e41e2cb8ffa9 100644
--- a/tools/testing/selftests/kvm/s390x/resets.c
+++ b/tools/testing/selftests/kvm/s390x/resets.c
@@ -296,8 +296,6 @@ int main(int argc, char *argv[])
 	bool has_s390_vcpu_resets = kvm_check_cap(KVM_CAP_S390_VCPU_RESETS);
 	int idx;
 
-	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
-
 	ksft_print_header();
 	ksft_set_plan(ARRAY_SIZE(testlist));
 
diff --git a/tools/testing/selftests/kvm/s390x/sync_regs_test.c b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
index 3fdb6e2598eb..2ddde41c44ba 100644
--- a/tools/testing/selftests/kvm/s390x/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
@@ -231,9 +231,6 @@ int main(int argc, char *argv[])
 
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_SYNC_REGS));
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	ksft_print_header();
 
 	ksft_set_plan(ARRAY_SIZE(testlist));
diff --git a/tools/testing/selftests/kvm/set_memory_region_test.c b/tools/testing/selftests/kvm/set_memory_region_test.c
index 0d55f508d595..614141d6e53d 100644
--- a/tools/testing/selftests/kvm/set_memory_region_test.c
+++ b/tools/testing/selftests/kvm/set_memory_region_test.c
@@ -392,9 +392,6 @@ int main(int argc, char *argv[])
 	int i, loops;
 #endif
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 #ifdef __x86_64__
 	/*
 	 * FIXME: the zero-memslot test fails on aarch64 and s390x because
diff --git a/tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c b/tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c
index 4208487652f8..1027a671c7d3 100644
--- a/tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c
+++ b/tools/testing/selftests/kvm/x86_64/cr4_cpuid_sync_test.c
@@ -57,9 +57,6 @@ int main(int argc, char *argv[])
 
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_XSAVE));
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 	run = vcpu->run;
 
diff --git a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
index 236e11755ba6..3334adcfd591 100644
--- a/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
+++ b/tools/testing/selftests/kvm/x86_64/emulator_error_test.c
@@ -156,9 +156,6 @@ int main(int argc, char *argv[])
 	uint64_t *hva;
 	int rc;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_SMALLER_MAXPHYADDR));
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c b/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c
index e804eb08dff9..5c27efbf405e 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_cpuid.c
@@ -134,9 +134,6 @@ int main(int argc, char *argv[])
 	const struct kvm_cpuid2 *hv_cpuid_entries;
 	struct kvm_vcpu *vcpu;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_HYPERV_CPUID));
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
diff --git a/tools/testing/selftests/kvm/x86_64/platform_info_test.c b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
index 76417c7d687b..310a104d94f0 100644
--- a/tools/testing/selftests/kvm/x86_64/platform_info_test.c
+++ b/tools/testing/selftests/kvm/x86_64/platform_info_test.c
@@ -72,9 +72,6 @@ int main(int argc, char *argv[])
 	struct kvm_vm *vm;
 	uint64_t msr_platform_info;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_MSR_PLATFORM_INFO));
 
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
diff --git a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
index ea4e259a1e2e..a6ffa245c897 100644
--- a/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
+++ b/tools/testing/selftests/kvm/x86_64/pmu_event_filter_test.c
@@ -447,9 +447,6 @@ int main(int argc, char *argv[])
 	struct kvm_vcpu *vcpu;
 	struct kvm_vm *vm;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_PMU_EVENT_FILTER));
 
 	TEST_REQUIRE(use_intel_pmu() || use_amd_pmu());
diff --git a/tools/testing/selftests/kvm/x86_64/set_sregs_test.c b/tools/testing/selftests/kvm/x86_64/set_sregs_test.c
index 2bb08bf2125d..a284fcef6ed7 100644
--- a/tools/testing/selftests/kvm/x86_64/set_sregs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/set_sregs_test.c
@@ -82,9 +82,6 @@ int main(int argc, char *argv[])
 	uint64_t cr4;
 	int rc;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	/*
 	 * Create a dummy VM, specifically to avoid doing KVM_SET_CPUID2, and
 	 * use it to verify all supported CR4 bits can be set prior to defining
diff --git a/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c b/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c
index e637d7736012..e497ace629c1 100644
--- a/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c
+++ b/tools/testing/selftests/kvm/x86_64/svm_nested_soft_inject_test.c
@@ -194,9 +194,6 @@ static void run_test(bool is_nmi)
 
 int main(int argc, char *argv[])
 {
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_SVM));
 
 	TEST_ASSERT(kvm_cpu_has(X86_FEATURE_NRIPS),
diff --git a/tools/testing/selftests/kvm/x86_64/sync_regs_test.c b/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
index 9b6db0b0b13e..d2f9b5bdfab2 100644
--- a/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sync_regs_test.c
@@ -90,9 +90,6 @@ int main(int argc, char *argv[])
 	struct kvm_vcpu_events events;
 	int rv, cap;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	cap = kvm_check_cap(KVM_CAP_SYNC_REGS);
 	TEST_REQUIRE((cap & TEST_SYNC_FIELDS) == TEST_SYNC_FIELDS);
 	TEST_REQUIRE(!(cap & INVALID_SYNC_FIELD));
diff --git a/tools/testing/selftests/kvm/x86_64/userspace_io_test.c b/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
index 7316521428f8..91076c9787b4 100644
--- a/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
+++ b/tools/testing/selftests/kvm/x86_64/userspace_io_test.c
@@ -56,9 +56,6 @@ int main(int argc, char *argv[])
 	struct kvm_vm *vm;
 	struct ucall uc;
 
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 	run = vcpu->run;
 
diff --git a/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c b/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
index fae95089e655..25fa55344a10 100644
--- a/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
+++ b/tools/testing/selftests/kvm/x86_64/userspace_msr_exit_test.c
@@ -818,9 +818,6 @@ static void test_user_exit_msr_flags(void)
 
 int main(int argc, char *argv[])
 {
-	/* Tell stdout not to buffer its content */
-	setbuf(stdout, NULL);
-
 	test_msr_filter_allow();
 
 	test_msr_filter_deny();
-- 
2.38.1.431.g37b22c650d-goog

[V4 PATCH 2/3] KVM: selftests: Add arch specific initialization

[Vishal Annapurve]

Introduce arch specific API: kvm_selftest_arch_init to allow each arch to
handle initialization before running any selftest logic.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
 .../selftests/kvm/include/kvm_util_base.h      |  5 +++++
 .../selftests/kvm/lib/aarch64/processor.c      | 18 +++++++++---------
 tools/testing/selftests/kvm/lib/kvm_util.c     |  6 ++++++
 3 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index e42a09cd24a0..eec0e4898efe 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -838,4 +838,9 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
 	return __vm_enable_cap(vm, KVM_CAP_VM_DISABLE_NX_HUGE_PAGES, 0);
 }
 
+/*
+ * API to execute architecture specific setup before executing main().
+ */
+void kvm_selftest_arch_init(void);
+
 #endif /* SELFTEST_KVM_UTIL_BASE_H */
diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
index 6f5551368944..0de4aabc0c76 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
@@ -495,15 +495,6 @@ void aarch64_get_supported_page_sizes(uint32_t ipa,
 	close(kvm_fd);
 }
 
-/*
- * arm64 doesn't have a true default mode, so start by computing the
- * available IPA space and page sizes early.
- */
-void __attribute__((constructor)) init_guest_modes(void)
-{
-       guest_modes_append_default();
-}
-
 void smccc_hvc(uint32_t function_id, uint64_t arg0, uint64_t arg1,
 	       uint64_t arg2, uint64_t arg3, uint64_t arg4, uint64_t arg5,
 	       uint64_t arg6, struct arm_smccc_res *res)
@@ -528,3 +519,12 @@ void smccc_hvc(uint32_t function_id, uint64_t arg0, uint64_t arg1,
 		       [arg4] "r"(arg4), [arg5] "r"(arg5), [arg6] "r"(arg6)
 		     : "x0", "x1", "x2", "x3", "x4", "x5", "x6", "x7");
 }
+
+void kvm_selftest_arch_init(void)
+{
+	/*
+	 * arm64 doesn't have a true default mode, so start by computing the
+	 * available IPA space and page sizes early.
+	 */
+	guest_modes_append_default();
+}
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 37d7d144c74e..deb4c731b9fa 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -2022,8 +2022,14 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 	}
 }
 
+__weak void kvm_selftest_arch_init(void)
+{
+}
+
 void __attribute((constructor)) kvm_selftest_init(void)
 {
 	/* Tell stdout not to buffer its content. */
 	setbuf(stdout, NULL);
+
+	kvm_selftest_arch_init();
 }
-- 
2.38.1.431.g37b22c650d-goog

[V4 PATCH 3/3] KVM: selftests: Add arch specific post vm creation hook

[Vishal Annapurve]

Add arch specific API kvm_arch_vm_post_create to perform any required setup
after VM creation.

Suggested-by: Sean Christopherson <seanjc@google.com>
Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Vishal Annapurve <vannapurve@google.com>
---
 tools/testing/selftests/kvm/include/kvm_util_base.h | 4 ++++
 tools/testing/selftests/kvm/lib/kvm_util.c          | 9 ++++++---
 tools/testing/selftests/kvm/lib/x86_64/processor.c  | 6 ++++++
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
index eec0e4898efe..1e7d3eae8c91 100644
--- a/tools/testing/selftests/kvm/include/kvm_util_base.h
+++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
@@ -843,4 +843,8 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
  */
 void kvm_selftest_arch_init(void);
 
+/*
+ * API to execute architecture specific setup after creating the VM.
+ */
+void kvm_arch_vm_post_create(struct kvm_vm *vm);
 #endif /* SELFTEST_KVM_UTIL_BASE_H */
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index deb4c731b9fa..3ed72980c996 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -340,9 +340,8 @@ struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint32_t nr_runnable_vcpus,
 
 	kvm_vm_elf_load(vm, program_invocation_name);
 
-#ifdef __x86_64__
-	vm_create_irqchip(vm);
-#endif
+	kvm_arch_vm_post_create(vm);
+
 	return vm;
 }
 
@@ -2022,6 +2021,10 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
 	}
 }
 
+__weak void kvm_arch_vm_post_create(struct kvm_vm *vm)
+{
+}
+
 __weak void kvm_selftest_arch_init(void)
 {
 }
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 39c4409ef56a..fa65e8142c16 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -1327,3 +1327,9 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm)
 
 	return get_kvm_intel_param_bool("unrestricted_guest");
 }
+
+
+void kvm_arch_vm_post_create(struct kvm_vm *vm)
+{
+	vm_create_irqchip(vm);
+}
-- 
2.38.1.431.g37b22c650d-goog

Re: [V4 PATCH 1/3] KVM: selftests: move common startup logic to kvm_util.c

[Sean Christopherson]

On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> Consolidate common startup logic in one place by implementing a single
> setup function with __attribute((constructor)) for all selftests within
> kvm_util.c.
> 
> This allows moving logic like:
>         /* Tell stdout not to buffer its content */
>         setbuf(stdout, NULL);
> to a single file for all selftests.
> 
> This will also allow any required setup at entry in future to be done in
> common main function.
> 
> More context is discussed at:
> https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com/

Nit,

  Link: https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com

is the the "standard" way to convey this information.

Re: [V4 PATCH 3/3] KVM: selftests: Add arch specific post vm creation hook

[Sean Christopherson]

On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> Add arch specific API kvm_arch_vm_post_create to perform any required setup
> after VM creation.
> 
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
> Reviewed-by: Peter Gonda <pgonda@google.com>
> Signed-off-by: Vishal Annapurve <vannapurve@google.com>
> ---
>  tools/testing/selftests/kvm/include/kvm_util_base.h | 4 ++++
>  tools/testing/selftests/kvm/lib/kvm_util.c          | 9 ++++++---
>  tools/testing/selftests/kvm/lib/x86_64/processor.c  | 6 ++++++
>  3 files changed, 16 insertions(+), 3 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
> index eec0e4898efe..1e7d3eae8c91 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util_base.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
> @@ -843,4 +843,8 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
>   */
>  void kvm_selftest_arch_init(void);
>  
> +/*
> + * API to execute architecture specific setup after creating the VM.
> + */

Meh, I think the function name is self-explanatory.

> +void kvm_arch_vm_post_create(struct kvm_vm *vm);
>  #endif /* SELFTEST_KVM_UTIL_BASE_H */
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index deb4c731b9fa..3ed72980c996 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -340,9 +340,8 @@ struct kvm_vm *__vm_create(enum vm_guest_mode mode, uint32_t nr_runnable_vcpus,
>  
>  	kvm_vm_elf_load(vm, program_invocation_name);
>  
> -#ifdef __x86_64__
> -	vm_create_irqchip(vm);
> -#endif
> +	kvm_arch_vm_post_create(vm);
> +
>  	return vm;
>  }
>  
> @@ -2022,6 +2021,10 @@ void __vm_get_stat(struct kvm_vm *vm, const char *stat_name, uint64_t *data,
>  	}
>  }
>  
> +__weak void kvm_arch_vm_post_create(struct kvm_vm *vm)
> +{
> +}
> +
>  __weak void kvm_selftest_arch_init(void)
>  {
>  }
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 39c4409ef56a..fa65e8142c16 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -1327,3 +1327,9 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm)
>  
>  	return get_kvm_intel_param_bool("unrestricted_guest");
>  }
> +
> +

Extra newline.

> +void kvm_arch_vm_post_create(struct kvm_vm *vm)
> +{
> +	vm_create_irqchip(vm);
> +}
> -- 
> 2.38.1.431.g37b22c650d-goog
> 

Re: [V4 PATCH 2/3] KVM: selftests: Add arch specific initialization

[Sean Christopherson]

On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> Introduce arch specific API: kvm_selftest_arch_init to allow each arch to
> handle initialization before running any selftest logic.
> 
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
> Reviewed-by: Peter Gonda <pgonda@google.com>
> Signed-off-by: Vishal Annapurve <vannapurve@google.com>
> ---
>  .../selftests/kvm/include/kvm_util_base.h      |  5 +++++
>  .../selftests/kvm/lib/aarch64/processor.c      | 18 +++++++++---------
>  tools/testing/selftests/kvm/lib/kvm_util.c     |  6 ++++++
>  3 files changed, 20 insertions(+), 9 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
> index e42a09cd24a0..eec0e4898efe 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util_base.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
> @@ -838,4 +838,9 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
>  	return __vm_enable_cap(vm, KVM_CAP_VM_DISABLE_NX_HUGE_PAGES, 0);
>  }
>  
> +/*
> + * API to execute architecture specific setup before executing main().
> + */

I find the "API" blurb to be somewhat confusing.  When I think of APIs, I think
of functions that are provided by a library that are called by users of the
library.

An example might also help readers understand what types of setup can/should be
done with this hook.

Maybe something like this?

/*
 * Arch hook that is invoked via a constructor, i.e. before exeucting main(),
 * to allow for arch-specific setup that is common to all tests, e.g. computing
 * the default guest "mode".
 */

Re: [V4 PATCH 0/3] Minor improvements to the selftest setup logic

[Sean Christopherson]

On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> This series is posted in context of the discussion at:
> https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com/
> 
> Major changes:
> 1) Move common startup logic to a single function in kvm_util.c
> 2) Introduce following APIs:
> 	kvm_selftest_arch_init: to perform arch specific common startup.
> 	kvm_arch_vm_post_create: to perform arch specific common setup
> 		after VM creation.

Looks good!  A few uber nits, but nothing that can't be fixed up when applying.

Re: [V4 PATCH 1/3] KVM: selftests: move common startup logic to kvm_util.c

[Vishal Annapurve]

On Wed, Nov 16, 2022 at 9:36 AM Sean Christopherson <seanjc@google.com> wrote:
>
> On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> > Consolidate common startup logic in one place by implementing a single
> > setup function with __attribute((constructor)) for all selftests within
> > kvm_util.c.
> >
> > This allows moving logic like:
> >         /* Tell stdout not to buffer its content */
> >         setbuf(stdout, NULL);
> > to a single file for all selftests.
> >
> > This will also allow any required setup at entry in future to be done in
> > common main function.
> >
> > More context is discussed at:
> > https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com/
>
> Nit,
>
>   Link: https://lore.kernel.org/lkml/Ywa9T+jKUpaHLu%2Fl@google.com
>
> is the the "standard" way to convey this information.

Noted.

Re: [V4 PATCH 2/3] KVM: selftests: Add arch specific initialization

[Vishal Annapurve]

On Wed, Nov 16, 2022 at 9:46 AM Sean Christopherson <seanjc@google.com> wrote:
>
> On Tue, Nov 15, 2022, Vishal Annapurve wrote:
> > Introduce arch specific API: kvm_selftest_arch_init to allow each arch to
> > handle initialization before running any selftest logic.
> >
> > Suggested-by: Sean Christopherson <seanjc@google.com>
> > Reviewed-by: Andrew Jones <andrew.jones@linux.dev>
> > Reviewed-by: Peter Gonda <pgonda@google.com>
> > Signed-off-by: Vishal Annapurve <vannapurve@google.com>
> > ---
> >  .../selftests/kvm/include/kvm_util_base.h      |  5 +++++
> >  .../selftests/kvm/lib/aarch64/processor.c      | 18 +++++++++---------
> >  tools/testing/selftests/kvm/lib/kvm_util.c     |  6 ++++++
> >  3 files changed, 20 insertions(+), 9 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/include/kvm_util_base.h b/tools/testing/selftests/kvm/include/kvm_util_base.h
> > index e42a09cd24a0..eec0e4898efe 100644
> > --- a/tools/testing/selftests/kvm/include/kvm_util_base.h
> > +++ b/tools/testing/selftests/kvm/include/kvm_util_base.h
> > @@ -838,4 +838,9 @@ static inline int __vm_disable_nx_huge_pages(struct kvm_vm *vm)
> >       return __vm_enable_cap(vm, KVM_CAP_VM_DISABLE_NX_HUGE_PAGES, 0);
> >  }
> >
> > +/*
> > + * API to execute architecture specific setup before executing main().
> > + */
>
> I find the "API" blurb to be somewhat confusing.  When I think of APIs, I think
> of functions that are provided by a library that are called by users of the
> library.
>
> An example might also help readers understand what types of setup can/should be
> done with this hook.
>
> Maybe something like this?
>
> /*
>  * Arch hook that is invoked via a constructor, i.e. before exeucting main(),
>  * to allow for arch-specific setup that is common to all tests, e.g. computing
>  * the default guest "mode".
>  */

Ack, that looks better.