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: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221020054202.2119018-10-reijiw@google.com

diff --git a/tools/testing/selftests/kvm/aarch64/debug-exceptions.c b/tools/testing/selftests/kvm/aarch64/debug-exceptions.c
index 73a95e6b345e55c1214062810aea6175a72fcdbe..b30add3e77269a331a82f1c0bacf4f0d1da8188c 100644 (file)
--- a/tools/testing/selftests/kvm/aarch64/debug-exceptions.c
+++ b/tools/testing/selftests/kvm/aarch64/debug-exceptions.c
@@ -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;