diff --git a/kernel/pkg_observer.c b/kernel/pkg_observer.c
index e0641332..ae5ee23d 100644
--- a/kernel/pkg_observer.c
+++ b/kernel/pkg_observer.c
@@ -2,8 +2,9 @@
 #include <linux/module.h>
 #include <linux/fs.h>
 #include <linux/namei.h>
-#include <linux/fsnotify_backend.h>
+#include <linux/fsnotify.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 #include <linux/rculist.h>
 #include <linux/version.h>
 #include "klog.h" // IWYU pragma: keep
@@ -23,6 +24,7 @@ struct watch_dir {
 
 static struct fsnotify_group *g;
 
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
 static int ksu_handle_inode_event(struct fsnotify_mark *mark, u32 mask,
                   struct inode *inode, struct inode *dir,
                   const struct qstr *file_name, u32 cookie)
@@ -41,9 +43,58 @@ static int ksu_handle_inode_event(struct fsnotify_mark *mark, u32 mask,
     }
     return 0;
 }
+#else
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 2, 0)
+static int ksu_handle_event(struct fsnotify_group *group,
+	struct inode *inode, u32 mask, const void *data, int data_type,
+	const struct qstr *file_name, u32 cookie,
+	struct fsnotify_iter_info *iter_info)
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 18, 0)
+static int ksu_handle_event(struct fsnotify_group *group,
+	struct inode *inode, u32 mask, const void *data, int data_type,
+	const unsigned char *file_name, u32 cookie,
+	struct fsnotify_iter_info *iter_info)
+#elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 12, 0)
+static int ksu_handle_event(struct fsnotify_group *group,
+	struct inode *inode, struct fsnotify_mark *inode_mark,
+	struct fsnotify_mark *vfsmount_mark,
+	u32 mask, const void *data, int data_type,
+	const unsigned char *file_name, u32 cookie,
+	struct fsnotify_iter_info *iter_info)
+#else
+static int ksu_handle_event(struct fsnotify_group *group,
+	struct inode *inode,
+	struct fsnotify_mark *inode_mark,
+	struct fsnotify_mark *vfsmount_mark,
+	u32 mask, void *data, int data_type,
+	const unsigned char *file_name, u32 cookie)
+#endif
+{
+	if (!file_name)
+		return 0;
+	if (mask & FS_ISDIR)
+		return 0;
+
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 2, 0)
+	if (file_name->len == 13 &&
+		!memcmp(file_name->name, "packages.list", 13)) {
+#else
+	if (strlen(file_name) == 13 &&
+		!memcmp(file_name, "packages.list", 13)) {
+#endif
+			pr_info("packages.list detected: %d\n", mask);
+			track_throne();
+	}
+	return 0;
+}
+#endif
 
 static const struct fsnotify_ops ksu_ops = {
-    .handle_inode_event = ksu_handle_inode_event,
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 9, 0)
+	.handle_inode_event = ksu_handle_inode_event,
+#else
+	.handle_event = ksu_handle_event,
+#endif
 };
 
 static int add_mark_on_inode(struct inode *inode, u32 mask,
@@ -58,12 +109,23 @@ static int add_mark_on_inode(struct inode *inode, u32 mask,
     fsnotify_init_mark(m, g);
     m->mask = mask;
 
-    if (fsnotify_add_inode_mark(m, inode, 0)) {
-        fsnotify_put_mark(m);
-        return -EINVAL;
-    }
-    *out = m;
-    return 0;
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 12, 0)
+	if (fsnotify_add_inode_mark(m, inode, 0)) {
+		fsnotify_put_mark(m);
+		return -EINVAL;
+	}
+#else /* TODO: Need more tests on k4.4 and k4.9! */
+	mutex_lock(&g->mark_mutex);
+	if (fsnotify_add_mark_locked(m, g, inode, NULL, 0)) {
+		fsnotify_put_mark(m);
+		mutex_unlock(&g->mark_mutex);
+		return -EINVAL;
+	}
+	mutex_unlock(&g->mark_mutex);
+#endif
+
+	*out = m;
+	return 0;
 }
 
 static int watch_one_dir(struct watch_dir *wd)