livepatch: Print logs when check calltrace failed

hulk inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I53WZ9

--------------------------------
Signed-off-by: NZheng Yejian <zhengyejian1@huawei.com>
Reviewed-by: NKuohai Xu <xukuohai@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

arch/arm/kernel/livepatch.c

@@ -283,8 +283,10 @@ int klp_check_calltrace(struct klp_patch *patch, int enable)
 	};
 
 	ret = klp_check_activeness_func(patch, enable, &check_funcs);
-	if (ret)
+	if (ret) {
+		pr_err("collect active functions failed, ret=%d\n", ret);
 		goto out;
+	}
 	args.check_funcs = check_funcs;
 
 	for_each_process_thread(g, t) {

arch/arm64/kernel/livepatch.c

@@ -276,8 +276,10 @@ int klp_check_calltrace(struct klp_patch *patch, int enable)
 	};
 
 	ret = klp_check_activeness_func(patch, enable, &check_funcs);
-	if (ret)
+	if (ret) {
+		pr_err("collect active functions failed, ret=%d\n", ret);
 		goto out;
+	}
 	args.check_funcs = check_funcs;
 
 	for_each_process_thread(g, t) {

arch/powerpc/kernel/livepatch_32.c

@@ -311,8 +311,10 @@ int klp_check_calltrace(struct klp_patch *patch, int enable)
 	};
 
 	ret = klp_check_activeness_func(patch, enable, &check_funcs);
-	if (ret)
+	if (ret) {
+		pr_err("collect active functions failed, ret=%d\n", ret);
 		goto out;
+	}
 	args.check_funcs = check_funcs;
 
 	for_each_process_thread(g, t) {

arch/powerpc/kernel/livepatch_64.c

@@ -359,8 +359,10 @@ int klp_check_calltrace(struct klp_patch *patch, int enable)
 	struct walk_stackframe_args args;
 
 	ret = klp_check_activeness_func(patch, enable, &check_funcs);
-	if (ret)
+	if (ret) {
+		pr_err("collect active functions failed, ret=%d\n", ret);
 		goto out;
+	}
 	args.check_funcs = check_funcs;
 	args.ret = 0;
 

arch/x86/kernel/livepatch.c

@@ -321,38 +321,42 @@ int klp_check_calltrace(struct klp_patch *patch, int enable)
 #endif
 
 	ret = klp_check_activeness_func(patch, enable, &check_funcs);
-	if (ret)
+	if (ret) {
+		pr_err("collect active functions failed, ret=%d\n", ret);
 		goto out;
+	}
 	for_each_process_thread(g, t) {
 		if (!strncmp(t->comm, "migration/", 10))
 			continue;
 
 #ifdef CONFIG_ARCH_STACKWALK
 		ret = stack_trace_save_tsk_reliable(t, trace_entries, MAX_STACK_ENTRIES);
-		if (ret < 0)
+		if (ret < 0) {
+			pr_err("%s:%d has an unreliable stack, ret=%d\n",
+			       t->comm, t->pid, ret);
 			goto out;
+		}
 		trace_len = ret;
-		ret = 0;
+		ret = klp_check_stack(trace_entries, trace_len, check_funcs);
 #else
 		trace.skip = 0;
 		trace.nr_entries = 0;
 		trace.max_entries = MAX_STACK_ENTRIES;
 		trace.entries = trace_entries;
 		ret = save_stack_trace_tsk_reliable(t, &trace);
-#endif
 		WARN_ON_ONCE(ret == -ENOSYS);
 		if (ret) {
-			pr_info("%s: %s:%d has an unreliable stack\n",
-				 __func__, t->comm, t->pid);
+			pr_err("%s: %s:%d has an unreliable stack, ret=%d\n",
+			       __func__, t->comm, t->pid, ret);
 			goto out;
 		}
-#ifdef CONFIG_ARCH_STACKWALK
-		ret = klp_check_stack(trace_entries, trace_len, check_funcs);
-#else
 		ret = klp_check_stack(&trace, 0, check_funcs);
 #endif
-		if (ret)
+		if (ret) {
+			pr_err("%s:%d check stack failed, ret=%d\n",
+			       t->comm, t->pid, ret);
 			goto out;
+		}
 	}
 
 out: