diff --git a/Documentation/git-pack-objects.txt b/Documentation/git-pack-objects.txt
index 81bc490ac52eb9414015979d8c244ce063c838b5..44245e5815e7b6bf8b2b090a1ec2832dd28aa215 100644
--- a/Documentation/git-pack-objects.txt
+++ b/Documentation/git-pack-objects.txt
@@ -267,6 +267,19 @@ Unexpected missing object will raise an error.
 	locally created objects [without .promisor] and objects from the
 	promisor remote [with .promisor].)  This is used with partial clone.
 
+--keep-unreachable::
+	Objects unreachable from the refs in packs named with
+	--unpacked= option are added to the resulting pack, in
+	addition to the reachable objects that are not in packs marked
+	with *.keep files. This implies `--revs`.
+
+--pack-loose-unreachable::
+	Pack unreachable loose objects (and their loose counterparts
+	removed). This implies `--revs`.
+
+--unpack-unreachable::
+	Keep unreachable objects in loose form. This implies `--revs`.
+
 SEE ALSO
 --------
 linkgit:git-rev-list[1]
diff --git a/builtin/pack-objects.c b/builtin/pack-objects.c
index e9d3cfb9e33a6b874751ac6acc5aac2361d4a58d..b0f3e462f377b590341ef05715e36b8e7ff788b7 100644
--- a/builtin/pack-objects.c
+++ b/builtin/pack-objects.c
@@ -3087,6 +3087,8 @@ int cmd_pack_objects(int argc, const char **argv, const char *prefix)
 		fetch_if_missing = 0;
 		argv_array_push(&rp, "--exclude-promisor-objects");
 	}
+	if (unpack_unreachable || keep_unreachable || pack_loose_unreachable)
+		use_internal_rev_list = 1;
 
 	if (!reuse_object)
 		reuse_delta = 0;