diff --git a/dm-sflc/src/lite/discard.c b/dm-sflc/src/lite/discard.c
index 172257c..d41d59b 100644
--- a/dm-sflc/src/lite/discard.c
+++ b/dm-sflc/src/lite/discard.c
@@ -60,6 +60,9 @@ unlock:
 	up_read(&svol->posmap.flush_lock);
 
 	/* Done */
+	/* WARNING: it is crucial that the original bio is terminated here and never 
+	   reaches the block device, otherwise the effect of a TRIM on the block device 
+	   would be obvious, and likely to break plausible deniability */
 	bio_endio(orig_bio);
 	return;
 }
diff --git a/dm-sflc/src/lite/posmap.c b/dm-sflc/src/lite/posmap.c
index 95c46e9..8c0b57a 100644
--- a/dm-sflc/src/lite/posmap.c
+++ b/dm-sflc/src/lite/posmap.c
@@ -127,6 +127,8 @@ int sflite_destroy_local_slice_mapping(struct sflite_volume *svol, u32 lsi)
 	   so the counters must remain untouched to avoid confusion. */
 	// sdev->nr_free_slices++;
 	// svol->posmap.nr_mapped_slices--;
+	/* TODO: possible to improve by freeing up slices dynamically instead of 
+	   requiring reload/close-open? */
 
 	/* Set the dirty bit in position map */
 	__set_bit(lsi/SFLITE_PSIS_PER_BLOCK, svol->posmap.dirty_bitmap);