diff --git a/quota/linux-lib.pl b/quota/linux-lib.pl
index 188c0fb05..f37bf804e 100755
--- a/quota/linux-lib.pl
+++ b/quota/linux-lib.pl
@@ -1482,9 +1482,9 @@ return defined($_[0]) && $_[0] =~ /^\d+\/\d+$/ ? 1 : 0;
 
 Sets the referenced or exclusive byte limit for a Btrfs qgroup. If qgroup is
 undef, path must be a subvolume and its level-0 qgroup is changed. If bytes
-is undef, the limit is removed. If an exceeded limit blocks the update, quota
-enforcement is temporarily overridden for one retry. Returns undef on success
-or an error message on failure.
+is undef, the limit is removed. If quota enforcement on path or one of its
+parent qgroups blocks the transaction, it is temporarily overridden for one
+retry. Returns undef on success or an error message on failure.
 
 =cut
 sub set_btrfs_qgroup_limit
@@ -1502,9 +1502,10 @@ push(@args, $qgroup) if (defined($qgroup));
 push(@args, $path);
 my ($out, $err) = &run_btrfs_command(1, @args);
 
-# An exceeded qgroup can block the metadata write needed to raise or remove its
-# own limit. Retry once with the kernel's administrative override, preserving
-# the previous state and restoring enforcement immediately after the command.
+# A limit on the command path or one of its parent qgroups can block the
+# transaction needed to update any qgroup limit. Retry once with the kernel's
+# administrative override, preserving the previous state and restoring
+# enforcement immediately after the command.
 if ($err && $err =~ /disk quota exceeded/i) {
 	my $uuid = &btrfs_filesystem_uuid($path);
 	my $sysfs = $btrfs_sysfs_root || "/sys/fs/btrfs";
diff --git a/quota/save_btrfs.cgi b/quota/save_btrfs.cgi
index 7ec2ef454..f49a7b97e 100755
--- a/quota/save_btrfs.cgi
+++ b/quota/save_btrfs.cgi
@@ -68,8 +68,8 @@ $same_referenced = &same_limit(
 $same_exclusive = &same_limit(
 	$max_exclusive, $qgroup->{'max_exclusive'});
 
-# Apply only changed limits, keeping an unrelated existing over-limit setting
-# from causing Btrfs to reject an otherwise valid update.
+# Apply only changed limits so each independent setting is left untouched when
+# the submitted value already matches it.
 if (!$same_referenced) {
 	$err = &set_btrfs_qgroup_limit(
 		$dir, $in{'qgroup'}, $max_referenced, 0);
diff --git a/quota/t/run-tests.t b/quota/t/run-tests.t
index 5939a9bda..3485f61f4 100644
--- a/quota/t/run-tests.t
+++ b/quota/t/run-tests.t
@@ -287,8 +287,8 @@ is(main::set_btrfs_qgroup_limit("/srv/btrfs", "1/100", "1M"),
 is(main::assign_btrfs_qgroup("/srv/btrfs", "bad", "1/100"),
    "Invalid child Btrfs qgroup ID", "invalid child assignment is rejected");
 
-# An existing over-limit qgroup must not prevent an administrator from raising
-# or removing its limit. The kernel override is restored after the retry.
+# A qgroup-limit transaction rejected by quota enforcement is retried once,
+# and the kernel override is restored immediately afterward.
 my $override_root = tempdir(CLEANUP => 1);
 my $override_uuid = "abcdef01-2345-6789-abcd-ef0123456789";
 make_path("$override_root/$override_uuid");
@@ -305,12 +305,12 @@ local $main::btrfs_sysfs_root = $override_root;
 	{ 'out' => "", 'status' => 0 },
 	);
 is(main::set_btrfs_qgroup_limit("/srv/btrfs", "1/100", 2097152),
-   undef, "over-limit qgroup updates retry with the administrative override");
+   undef, "an EDQUOT limit update retries with the administrative override");
 open($override_fh, '<', "$override_root/$override_uuid/quota_override")
 	or die $!;
 is(<$override_fh>, "0\n", "quota enforcement is restored after the retry");
 close($override_fh);
-is(scalar(@commands), 3, "one status lookup and one limit retry are run");
+is(scalar(@commands), 3, "one UUID lookup and one limit retry are run");
 
 @responses = ({ 'out' => "ERROR: qgroup exists\n", 'status' => 1 });
 is(main::create_btrfs_qgroup("/srv/btrfs", "1/100"),