docs: add #1266 to TODO file

Signed-off-by: Karel Zak <>
diff --git a/Documentation/TODO b/Documentation/TODO
index 073826c..5c8cd96 100644
--- a/Documentation/TODO
+++ b/Documentation/TODO
@@ -16,6 +16,13 @@
   - add Coverity to GitHub Actions (see for example .github/workflows/coverity.yml
     in systemd repo).
+  - "fstrim --fstab" uses root= from /proc/cmdline to get root FS when it's missing
+    in fstab file. This is fragile (due to missing root= or the root FS is not 
+    accessible). The best seems to parse mountinfo and use mnt_table_get_root_fs()
+    as a fallback solution.
 script (lib/pty-session.c)
   - (!) add #ifdefs and optional code for non-signalfd() systems