diff --git a/fs/notify/fanotify/fanotify.c b/fs/notify/fanotify/fanotify.c
index cb58c6526edb..a5dd8b8d92b7 100644
--- a/fs/notify/fanotify/fanotify.c
+++ b/fs/notify/fanotify/fanotify.c
@@ -153,14 +153,16 @@ static u32 fanotify_group_event_mask(struct fsnotify_iter_info *iter_info,
 }
 
 static int fanotify_encode_fid(struct fanotify_event *event,
-			       const struct path *path, gfp_t gfp)
+			       const struct path *path, gfp_t gfp,
+			       __kernel_fsid_t *fsid)
 {
 	struct fanotify_fid *fid = &event->fid;
 	int dwords, bytes = 0;
-	struct kstatfs stat;
 	int err, type;
 
-	stat.f_fsid.val[0] = stat.f_fsid.val[1] = 0;
+	if (!fsid)
+		goto out_err;
+
 	fid->ext_fh = NULL;
 	dwords = 0;
 	err = -ENOENT;
@@ -168,10 +170,6 @@ static int fanotify_encode_fid(struct fanotify_event *event,
 	if (!dwords)
 		goto out_err;
 
-	err = vfs_statfs(path, &stat);
-	if (err)
-		goto out_err;
-
 	bytes = dwords << 2;
 	if (!fanotify_inline_fh_len(bytes)) {
 		/* Treat failure to allocate fh as failure to allocate event */
@@ -187,14 +185,14 @@ static int fanotify_encode_fid(struct fanotify_event *event,
 	if (!type || type == FILEID_INVALID || bytes != dwords << 2)
 		goto out_err;
 
-	fid->fsid = stat.f_fsid;
+	fid->fsid = *fsid;
 	event->fh_len = bytes;
 
 	return type;
 
 out_err:
 	pr_warn_ratelimited("fanotify: failed to encode fid (fsid=%x.%x, type=%d, bytes=%d, err=%i)\n",
-			    stat.f_fsid.val[0], stat.f_fsid.val[1],
+			    fsid ? fsid->val[0] : 0, fsid ? fsid->val[1] : 0,
 			    type, bytes, err);
 	kfree(fid->ext_fh);
 	fid->ext_fh = NULL;
@@ -204,8 +202,9 @@ static int fanotify_encode_fid(struct fanotify_event *event,
 }
 
 struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
-						 struct inode *inode, u32 mask,
-						 const struct path *path)
+					    struct inode *inode, u32 mask,
+					    const struct path *path,
+					    __kernel_fsid_t *fsid)
 {
 	struct fanotify_event *event = NULL;
 	gfp_t gfp = GFP_KERNEL_ACCOUNT;
@@ -244,7 +243,7 @@ init: __maybe_unused
 	event->fh_len = 0;
 	if (path && FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
 		/* Report the event without a file identifier on encode error */
-		event->fh_type = fanotify_encode_fid(event, path, gfp);
+		event->fh_type = fanotify_encode_fid(event, path, gfp, fsid);
 	} else if (path) {
 		event->fh_type = 0;
 		event->path = *path;
@@ -259,6 +258,28 @@ init: __maybe_unused
 	return event;
 }
 
+/*
+ * Get cached fsid of the filesystem containing the object from any connector.
+ * All connectors are supposed to have the same fsid, but we do not verify that
+ * here.
+ */
+static __kernel_fsid_t *fanotify_get_fsid(struct fsnotify_iter_info *iter_info,
+					  __kernel_fsid_t *fsid)
+{
+	int type;
+
+	fsnotify_foreach_obj_type(type) {
+		if (!fsnotify_iter_should_report_type(iter_info, type))
+			continue;
+
+		*fsid = iter_info->marks[type]->connector->fsid;
+		if (!WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1]))
+			return fsid;
+	}
+
+	return NULL;
+}
+
 static int fanotify_handle_event(struct fsnotify_group *group,
 				 struct inode *inode,
 				 u32 mask, const void *data, int data_type,
@@ -268,6 +289,7 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 	int ret = 0;
 	struct fanotify_event *event;
 	struct fsnotify_event *fsn_event;
+	__kernel_fsid_t __fsid, *fsid = NULL;
 
 	BUILD_BUG_ON(FAN_ACCESS != FS_ACCESS);
 	BUILD_BUG_ON(FAN_MODIFY != FS_MODIFY);
@@ -300,7 +322,10 @@ static int fanotify_handle_event(struct fsnotify_group *group,
 			return 0;
 	}
 
-	event = fanotify_alloc_event(group, inode, mask, data);
+	if (FAN_GROUP_FLAG(group, FAN_REPORT_FID))
+		fsid = fanotify_get_fsid(iter_info, &__fsid);
+
+	event = fanotify_alloc_event(group, inode, mask, data, fsid);
 	ret = -ENOMEM;
 	if (unlikely(!event)) {
 		/*
diff --git a/fs/notify/fanotify/fanotify.h b/fs/notify/fanotify/fanotify.h
index 265fbaa2d5b7..06b93cf227a2 100644
--- a/fs/notify/fanotify/fanotify.h
+++ b/fs/notify/fanotify/fanotify.h
@@ -135,5 +135,6 @@ static inline struct fanotify_event *FANOTIFY_E(struct fsnotify_event *fse)
 }
 
 struct fanotify_event *fanotify_alloc_event(struct fsnotify_group *group,
-						 struct inode *inode, u32 mask,
-						 const struct path *path);
+					    struct inode *inode, u32 mask,
+					    const struct path *path,
+					    __kernel_fsid_t *fsid);
diff --git a/fs/notify/fanotify/fanotify_user.c b/fs/notify/fanotify/fanotify_user.c
index 3b8d442e67cd..b69a7c23a765 100644
--- a/fs/notify/fanotify/fanotify_user.c
+++ b/fs/notify/fanotify/fanotify_user.c
@@ -649,7 +649,8 @@ static __u32 fanotify_mark_add_to_mask(struct fsnotify_mark *fsn_mark,
 
 static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
 						   fsnotify_connp_t *connp,
-						   unsigned int type)
+						   unsigned int type,
+						   __kernel_fsid_t *fsid)
 {
 	struct fsnotify_mark *mark;
 	int ret;
@@ -662,7 +663,7 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
 		return ERR_PTR(-ENOMEM);
 
 	fsnotify_init_mark(mark, group);
-	ret = fsnotify_add_mark_locked(mark, connp, type, 0);
+	ret = fsnotify_add_mark_locked_fsid(mark, connp, type, 0, fsid);
 	if (ret) {
 		fsnotify_put_mark(mark);
 		return ERR_PTR(ret);
@@ -674,7 +675,8 @@ static struct fsnotify_mark *fanotify_add_new_mark(struct fsnotify_group *group,
 
 static int fanotify_add_mark(struct fsnotify_group *group,
 			     fsnotify_connp_t *connp, unsigned int type,
-			     __u32 mask, unsigned int flags)
+			     __u32 mask, unsigned int flags,
+			     __kernel_fsid_t *fsid)
 {
 	struct fsnotify_mark *fsn_mark;
 	__u32 added;
@@ -682,7 +684,7 @@ static int fanotify_add_mark(struct fsnotify_group *group,
 	mutex_lock(&group->mark_mutex);
 	fsn_mark = fsnotify_find_mark(connp, group);
 	if (!fsn_mark) {
-		fsn_mark = fanotify_add_new_mark(group, connp, type);
+		fsn_mark = fanotify_add_new_mark(group, connp, type, fsid);
 		if (IS_ERR(fsn_mark)) {
 			mutex_unlock(&group->mark_mutex);
 			return PTR_ERR(fsn_mark);
@@ -699,23 +701,23 @@ static int fanotify_add_mark(struct fsnotify_group *group,
 
 static int fanotify_add_vfsmount_mark(struct fsnotify_group *group,
 				      struct vfsmount *mnt, __u32 mask,
-				      unsigned int flags)
+				      unsigned int flags, __kernel_fsid_t *fsid)
 {
 	return fanotify_add_mark(group, &real_mount(mnt)->mnt_fsnotify_marks,
-				 FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags);
+				 FSNOTIFY_OBJ_TYPE_VFSMOUNT, mask, flags, fsid);
 }
 
 static int fanotify_add_sb_mark(struct fsnotify_group *group,
-				      struct super_block *sb, __u32 mask,
-				      unsigned int flags)
+				struct super_block *sb, __u32 mask,
+				unsigned int flags, __kernel_fsid_t *fsid)
 {
 	return fanotify_add_mark(group, &sb->s_fsnotify_marks,
-				 FSNOTIFY_OBJ_TYPE_SB, mask, flags);
+				 FSNOTIFY_OBJ_TYPE_SB, mask, flags, fsid);
 }
 
 static int fanotify_add_inode_mark(struct fsnotify_group *group,
 				   struct inode *inode, __u32 mask,
-				   unsigned int flags)
+				   unsigned int flags, __kernel_fsid_t *fsid)
 {
 	pr_debug("%s: group=%p inode=%p\n", __func__, group, inode);
 
@@ -730,7 +732,7 @@ static int fanotify_add_inode_mark(struct fsnotify_group *group,
 		return 0;
 
 	return fanotify_add_mark(group, &inode->i_fsnotify_marks,
-				 FSNOTIFY_OBJ_TYPE_INODE, mask, flags);
+				 FSNOTIFY_OBJ_TYPE_INODE, mask, flags, fsid);
 }
 
 /* fanotify syscalls */
@@ -790,7 +792,7 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
 	atomic_inc(&user->fanotify_listeners);
 	group->memcg = get_mem_cgroup_from_mm(current->mm);
 
-	oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL);
+	oevent = fanotify_alloc_event(group, NULL, FS_Q_OVERFLOW, NULL, NULL);
 	if (unlikely(!oevent)) {
 		fd = -ENOMEM;
 		goto out_destroy_group;
@@ -853,9 +855,9 @@ SYSCALL_DEFINE2(fanotify_init, unsigned int, flags, unsigned int, event_f_flags)
 }
 
 /* Check if filesystem can encode a unique fid */
-static int fanotify_test_fid(struct path *path)
+static int fanotify_test_fid(struct path *path, struct kstatfs *stat)
 {
-	struct kstatfs stat, root_stat;
+	struct kstatfs root_stat;
 	struct path root = {
 		.mnt = path->mnt,
 		.dentry = path->dentry->d_sb->s_root,
@@ -865,11 +867,11 @@ static int fanotify_test_fid(struct path *path)
 	/*
 	 * Make sure path is not in filesystem with zero fsid (e.g. tmpfs).
 	 */
-	err = vfs_statfs(path, &stat);
+	err = vfs_statfs(path, stat);
 	if (err)
 		return err;
 
-	if (!stat.f_fsid.val[0] && !stat.f_fsid.val[1])
+	if (!stat->f_fsid.val[0] && !stat->f_fsid.val[1])
 		return -ENODEV;
 
 	/*
@@ -880,8 +882,8 @@ static int fanotify_test_fid(struct path *path)
 	if (err)
 		return err;
 
-	if (root_stat.f_fsid.val[0] != stat.f_fsid.val[0] ||
-	    root_stat.f_fsid.val[1] != stat.f_fsid.val[1])
+	if (root_stat.f_fsid.val[0] != stat->f_fsid.val[0] ||
+	    root_stat.f_fsid.val[1] != stat->f_fsid.val[1])
 		return -EXDEV;
 
 	/*
@@ -906,6 +908,8 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	struct fsnotify_group *group;
 	struct fd f;
 	struct path path;
+	struct kstatfs stat;
+	__kernel_fsid_t *fsid = NULL;
 	u32 valid_mask = FANOTIFY_EVENTS | FANOTIFY_EVENT_FLAGS;
 	unsigned int mark_type = flags & FANOTIFY_MARK_TYPE_BITS;
 	int ret;
@@ -984,9 +988,11 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 		goto fput_and_out;
 
 	if (FAN_GROUP_FLAG(group, FAN_REPORT_FID)) {
-		ret = fanotify_test_fid(&path);
+		ret = fanotify_test_fid(&path, &stat);
 		if (ret)
 			goto path_put_and_out;
+
+		fsid = &stat.f_fsid;
 	}
 
 	/* inode held in place by reference to path; group by fget on fd */
@@ -999,19 +1005,25 @@ static int do_fanotify_mark(int fanotify_fd, unsigned int flags, __u64 mask,
 	switch (flags & (FAN_MARK_ADD | FAN_MARK_REMOVE)) {
 	case FAN_MARK_ADD:
 		if (mark_type == FAN_MARK_MOUNT)
-			ret = fanotify_add_vfsmount_mark(group, mnt, mask, flags);
+			ret = fanotify_add_vfsmount_mark(group, mnt, mask,
+							 flags, fsid);
 		else if (mark_type == FAN_MARK_FILESYSTEM)
-			ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask, flags);
+			ret = fanotify_add_sb_mark(group, mnt->mnt_sb, mask,
+						   flags, fsid);
 		else
-			ret = fanotify_add_inode_mark(group, inode, mask, flags);
+			ret = fanotify_add_inode_mark(group, inode, mask,
+						      flags, fsid);
 		break;
 	case FAN_MARK_REMOVE:
 		if (mark_type == FAN_MARK_MOUNT)
-			ret = fanotify_remove_vfsmount_mark(group, mnt, mask, flags);
+			ret = fanotify_remove_vfsmount_mark(group, mnt, mask,
+							    flags);
 		else if (mark_type == FAN_MARK_FILESYSTEM)
-			ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask, flags);
+			ret = fanotify_remove_sb_mark(group, mnt->mnt_sb, mask,
+						      flags);
 		else
-			ret = fanotify_remove_inode_mark(group, inode, mask, flags);
+			ret = fanotify_remove_inode_mark(group, inode, mask,
+							 flags);
 		break;
 	default:
 		ret = -EINVAL;
diff --git a/fs/notify/mark.c b/fs/notify/mark.c
index d2dd16cb5989..9e71796dfbfb 100644
--- a/fs/notify/mark.c
+++ b/fs/notify/mark.c
@@ -82,6 +82,7 @@
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/srcu.h>
+#include <linux/ratelimit.h>
 
 #include <linux/atomic.h>
 
@@ -481,7 +482,8 @@ int fsnotify_compare_groups(struct fsnotify_group *a, struct fsnotify_group *b)
 }
 
 static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
-					       unsigned int type)
+					       unsigned int type,
+					       __kernel_fsid_t *fsid)
 {
 	struct inode *inode = NULL;
 	struct fsnotify_mark_connector *conn;
@@ -493,6 +495,11 @@ static int fsnotify_attach_connector_to_object(fsnotify_connp_t *connp,
 	INIT_HLIST_HEAD(&conn->list);
 	conn->type = type;
 	conn->obj = connp;
+	/* Cache fsid of filesystem containing the object */
+	if (fsid)
+		conn->fsid = *fsid;
+	else
+		conn->fsid.val[0] = conn->fsid.val[1] = 0;
 	if (conn->type == FSNOTIFY_OBJ_TYPE_INODE)
 		inode = igrab(fsnotify_conn_inode(conn));
 	/*
@@ -544,7 +551,7 @@ static struct fsnotify_mark_connector *fsnotify_grab_connector(
  */
 static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
 				  fsnotify_connp_t *connp, unsigned int type,
-				  int allow_dups)
+				  int allow_dups, __kernel_fsid_t *fsid)
 {
 	struct fsnotify_mark *lmark, *last = NULL;
 	struct fsnotify_mark_connector *conn;
@@ -553,15 +560,33 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
 
 	if (WARN_ON(!fsnotify_valid_obj_type(type)))
 		return -EINVAL;
+
+	/* Backend is expected to check for zero fsid (e.g. tmpfs) */
+	if (fsid && WARN_ON_ONCE(!fsid->val[0] && !fsid->val[1]))
+		return -ENODEV;
+
 restart:
 	spin_lock(&mark->lock);
 	conn = fsnotify_grab_connector(connp);
 	if (!conn) {
 		spin_unlock(&mark->lock);
-		err = fsnotify_attach_connector_to_object(connp, type);
+		err = fsnotify_attach_connector_to_object(connp, type, fsid);
 		if (err)
 			return err;
 		goto restart;
+	} else if (fsid &&
+		   (fsid->val[0] != conn->fsid.val[0] ||
+		    fsid->val[1] != conn->fsid.val[1])) {
+		/*
+		 * Backend is expected to check for non uniform fsid
+		 * (e.g. btrfs), but maybe we missed something?
+		 */
+		pr_warn_ratelimited("%s: fsid mismatch on object of type %u: %x.%x != %x.%x\n",
+				    __func__, conn->type,
+				    fsid->val[0], fsid->val[1],
+				    conn->fsid.val[0], conn->fsid.val[1]);
+		err = -EXDEV;
+		goto out_err;
 	}
 
 	/* is mark the first mark? */
@@ -604,9 +629,9 @@ static int fsnotify_add_mark_list(struct fsnotify_mark *mark,
  * These marks may be used for the fsnotify backend to determine which
  * event types should be delivered to which group.
  */
-int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
-			     fsnotify_connp_t *connp, unsigned int type,
-			     int allow_dups)
+int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark,
+				  fsnotify_connp_t *connp, unsigned int type,
+				  int allow_dups, __kernel_fsid_t *fsid)
 {
 	struct fsnotify_group *group = mark->group;
 	int ret = 0;
@@ -627,7 +652,7 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
 	fsnotify_get_mark(mark); /* for g_list */
 	spin_unlock(&mark->lock);
 
-	ret = fsnotify_add_mark_list(mark, connp, type, allow_dups);
+	ret = fsnotify_add_mark_list(mark, connp, type, allow_dups, fsid);
 	if (ret)
 		goto err;
 
@@ -648,13 +673,14 @@ int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
 }
 
 int fsnotify_add_mark(struct fsnotify_mark *mark, fsnotify_connp_t *connp,
-		      unsigned int type, int allow_dups)
+		      unsigned int type, int allow_dups, __kernel_fsid_t *fsid)
 {
 	int ret;
 	struct fsnotify_group *group = mark->group;
 
 	mutex_lock(&group->mark_mutex);
-	ret = fsnotify_add_mark_locked(mark, connp, type, allow_dups);
+	ret = fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups,
+					    fsid);
 	mutex_unlock(&group->mark_mutex);
 	return ret;
 }
diff --git a/include/linux/fsnotify_backend.h b/include/linux/fsnotify_backend.h
index 1e4b88bd1443..b66c4199d629 100644
--- a/include/linux/fsnotify_backend.h
+++ b/include/linux/fsnotify_backend.h
@@ -293,6 +293,7 @@ typedef struct fsnotify_mark_connector __rcu *fsnotify_connp_t;
 struct fsnotify_mark_connector {
 	spinlock_t lock;
 	unsigned int type;	/* Type of object [lock] */
+	__kernel_fsid_t fsid;	/* fsid of filesystem containing object */
 	union {
 		/* Object pointer [lock] */
 		fsnotify_connp_t *obj;
@@ -433,20 +434,32 @@ extern void fsnotify_init_mark(struct fsnotify_mark *mark,
 /* Find mark belonging to given group in the list of marks */
 extern struct fsnotify_mark *fsnotify_find_mark(fsnotify_connp_t *connp,
 						struct fsnotify_group *group);
+/* Get cached fsid of filesystem containing object */
+extern int fsnotify_get_conn_fsid(const struct fsnotify_mark_connector *conn,
+				  __kernel_fsid_t *fsid);
 /* attach the mark to the object */
 extern int fsnotify_add_mark(struct fsnotify_mark *mark,
 			     fsnotify_connp_t *connp, unsigned int type,
-			     int allow_dups);
-extern int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
-				    fsnotify_connp_t *connp, unsigned int type,
-				    int allow_dups);
+			     int allow_dups, __kernel_fsid_t *fsid);
+extern int fsnotify_add_mark_locked_fsid(struct fsnotify_mark *mark,
+					 fsnotify_connp_t *connp,
+					 unsigned int type, int allow_dups,
+					 __kernel_fsid_t *fsid);
+static inline int fsnotify_add_mark_locked(struct fsnotify_mark *mark,
+					   fsnotify_connp_t *connp,
+					   unsigned int type, int allow_dups)
+{
+	return fsnotify_add_mark_locked_fsid(mark, connp, type, allow_dups,
+					     NULL);
+}
+
 /* attach the mark to the inode */
 static inline int fsnotify_add_inode_mark(struct fsnotify_mark *mark,
 					  struct inode *inode,
 					  int allow_dups)
 {
 	return fsnotify_add_mark(mark, &inode->i_fsnotify_marks,
-				 FSNOTIFY_OBJ_TYPE_INODE, allow_dups);
+				 FSNOTIFY_OBJ_TYPE_INODE, allow_dups, NULL);
 }
 static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark,
 						 struct inode *inode,
@@ -455,6 +468,7 @@ static inline int fsnotify_add_inode_mark_locked(struct fsnotify_mark *mark,
 	return fsnotify_add_mark_locked(mark, &inode->i_fsnotify_marks,
 					FSNOTIFY_OBJ_TYPE_INODE, allow_dups);
 }
+
 /* given a group and a mark, flag mark to be freed when all references are dropped */
 extern void fsnotify_destroy_mark(struct fsnotify_mark *mark,
 				  struct fsnotify_group *group);
