Commit ebb8cc10 authored by Reiji Watanabe's avatar Reiji Watanabe Committed by Marc Zyngier
Browse files

KVM: arm64: selftests: Test with every breakpoint/watchpoint 



Currently, the debug-exceptions test always uses only
{break,watch}point#0 and the highest numbered context-aware
breakpoint. Modify the test to use all {break,watch}points and
context-aware breakpoints supported on the system.

Signed-off-by: default avatarReiji Watanabe <reijiw@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020054202.2119018-10-reijiw@google.com
parent 5ced4e53

tools/testing/selftests/kvm/aarch64/debug-exceptions.c

+42 −12
Original line number Diff line number Diff line
@@ -420,12 +420,11 @@ static int debug_version(uint64_t id_aa64dfr0) 
	return FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_DEBUGVER), id_aa64dfr0);

}



static void test_guest_debug_exceptions(uint64_t aa64dfr0)

static void test_guest_debug_exceptions(uint8_t bpn, uint8_t wpn, uint8_t ctx_bpn)

{

	struct kvm_vcpu *vcpu;

	struct kvm_vm *vm;

	struct ucall uc;

	uint8_t brp_num;



	vm = vm_create_with_one_vcpu(&vcpu, guest_code);

	ucall_init(vm, NULL);
@@ -444,15 +443,9 @@ static void test_guest_debug_exceptions(uint64_t aa64dfr0) 
	vm_install_sync_handler(vm, VECTOR_SYNC_CURRENT,

				ESR_EC_SVC64, guest_svc_handler);



	/* Number of breakpoints */

	brp_num = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_BRPS), aa64dfr0) + 1;

	__TEST_REQUIRE(brp_num >= 2, "At least two breakpoints are required");



	/*

	 * Run tests with breakpoint#0, watchpoint#0, and the higiest

	 * numbered (context-aware) breakpoint.

	 */

	vcpu_args_set(vcpu, 3, 0, 0, brp_num - 1);

	/* Specify bpn/wpn/ctx_bpn to be tested */

	vcpu_args_set(vcpu, 3, bpn, wpn, ctx_bpn);

	pr_debug("Use bpn#%d, wpn#%d and ctx_bpn#%d\n", bpn, wpn, ctx_bpn);



	vcpu_run(vcpu);

	switch (get_ucall(vcpu, &uc)) {
@@ -535,6 +528,43 @@ void test_single_step_from_userspace(int test_cnt) 
	kvm_vm_free(vm);

}



/*

 * Run debug testing using the various breakpoint#, watchpoint# and

 * context-aware breakpoint# with the given ID_AA64DFR0_EL1 configuration.

 */

void test_guest_debug_exceptions_all(uint64_t aa64dfr0)

{

	uint8_t brp_num, wrp_num, ctx_brp_num, normal_brp_num, ctx_brp_base;

	int b, w, c;



	/* Number of breakpoints */

	brp_num = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_BRPS), aa64dfr0) + 1;

	__TEST_REQUIRE(brp_num >= 2, "At least two breakpoints are required");



	/* Number of watchpoints */

	wrp_num = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_WRPS), aa64dfr0) + 1;



	/* Number of context aware breakpoints */

	ctx_brp_num = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64DFR0_CTX_CMPS), aa64dfr0) + 1;



	pr_debug("%s brp_num:%d, wrp_num:%d, ctx_brp_num:%d\n", __func__,

		 brp_num, wrp_num, ctx_brp_num);



	/* Number of normal (non-context aware) breakpoints */

	normal_brp_num = brp_num - ctx_brp_num;



	/* Lowest context aware breakpoint number */

	ctx_brp_base = normal_brp_num;



	/* Run tests with all supported breakpoints/watchpoints */

	for (c = ctx_brp_base; c < ctx_brp_base + ctx_brp_num; c++) {

		for (b = 0; b < normal_brp_num; b++) {

			for (w = 0; w < wrp_num; w++)

				test_guest_debug_exceptions(b, w, c);

		}

	}

}



static void help(char *name)

{

	puts("");
@@ -569,7 +599,7 @@ int main(int argc, char *argv[]) 
		}

	}



	test_guest_debug_exceptions(aa64dfr0);

	test_guest_debug_exceptions_all(aa64dfr0);

	test_single_step_from_userspace(ss_iteration);



	return 0;