diff --git a/kernel/core_hook.c b/kernel/core_hook.c
index 4c2f5e5f..1469f7ac 100644
--- a/kernel/core_hook.c
+++ b/kernel/core_hook.c
@@ -149,7 +149,7 @@ static inline bool is_allow_su(void)
 	return ksu_is_allow_uid(current_uid().val);
 }
 
-static inline bool is_unsupported_app_uid(uid_t uid)
+static inline bool is_unsupported_uid(uid_t uid)
 {
 #define LAST_APPLICATION_UID 19999
 	uid_t appid = uid % 100000;
@@ -1126,13 +1126,14 @@ int ksu_handle_prctl(int option, unsigned long arg2, unsigned long arg3,
 	return 0;
 }
 
-static bool is_non_appuid(kuid_t uid)
+static bool is_appuid(kuid_t uid)
 {
 #define PER_USER_RANGE 100000
 #define FIRST_APPLICATION_UID 10000
+#define LAST_APPLICATION_UID 19999
 
 	uid_t appid = uid.val % PER_USER_RANGE;
-	return appid < FIRST_APPLICATION_UID;
+	return appid >= FIRST_APPLICATION_UID && appid <= LAST_APPLICATION_UID;
 }
 
 static bool should_umount(struct path *path)
@@ -1327,19 +1328,14 @@ int ksu_handle_setuid(struct cred *new, const struct cred *old)
 	}
 #endif // #ifdef CONFIG_KSU_SUSFS
 
-	if (is_non_appuid(new_uid)) {
-#ifdef CONFIG_KSU_DEBUG
-		pr_info("handle setuid ignore non application uid: %d\n", new_uid.val);
-#endif
+	if (!is_appuid(new_uid) || is_unsupported_uid(new_uid.val)) {
+		// pr_info("handle setuid ignore non application or isolated uid: %d\n", new_uid.val);
 		return 0;
 	}
 
-	// isolated process may be directly forked from zygote, always unmount
-	if (is_unsupported_app_uid(new_uid.val)) {
-#ifdef CONFIG_KSU_DEBUG
-		pr_info("handle umount for unsupported application uid: %d\n", new_uid.val);
-#endif
-		goto do_umount;
+	if (ksu_is_allow_uid(new_uid.val)) {
+		// pr_info("handle setuid ignore allowed application: %d\n", new_uid.val);
+		return 0;
 	}
 
 	if (ksu_is_allow_uid(new_uid.val)) {
@@ -1372,11 +1368,13 @@ out_try_umount:
 		pr_info("uid: %d should not umount!\n", current_uid().val);
 #endif
 	}
-do_umount:
-	// check old process's selinux context, if it is not zygote, ignore it!
-	// because some su apps may setuid to untrusted_app but they are in global mount namespace
-	// when we umount for such process, that is a disaster!
-	if (!is_zygote(old->security)) {
+#ifndef CONFIG_KSU_SUSFS
+ 	// check old process's selinux context, if it is not zygote, ignore it!
+ 	// because some su apps may setuid to untrusted_app but they are in global mount namespace
+ 	// when we umount for such process, that is a disaster!
+	bool is_zygote_child = ksu_is_zygote(old->security);
+#endif
+	if (!is_zygote_child) {
 		pr_info("handle umount ignore non zygote child: %d\n",
 			current->pid);
 		return 0;