diff --git a/src/modules/fstab/fstab.conf b/src/modules/fstab/fstab.conf
index fdf0d41ec..385161d2d 100644
--- a/src/modules/fstab/fstab.conf
+++ b/src/modules/fstab/fstab.conf
@@ -11,9 +11,13 @@
 # Mount options to use for all filesystems. If a specific filesystem
 # is listed here, use those options, otherwise use the *default*
 # options from this mapping.
+#
+# With kernels 5.15 and newer be cautious of adding the option space_cache
+# to the btrfs mount options.  The default in 5.15 changed to space_cache=v2.
+# If space_cache or space_cache=v1 are specified, it may fail to remount.
 mountOptions:
     default: defaults,noatime
-    btrfs: defaults,noatime,space_cache,autodefrag,compress=zstd
+    btrfs: defaults,noatime,autodefrag,compress=zstd
 
 # Mount options to use for the EFI System Partition. If not defined, the
 # *mountOptions* for *vfat* are used, or if that is not set either,