diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index 8e6ddbb..57f01d2 100644
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -658,8 +658,11 @@
 			# getsockopt can EINVAL if SO_ACCEPTFILTER is unset:
 			my $x = getsockopt($s, SOL_SOCKET, $SO_ACCEPTFILTER);
 			return if ($x // '') =~ /[^\0]/s; # don't change if set
-			my $accf_arg = pack('a16a240', $af_name, '');
-			setsockopt $s, SOL_SOCKET, $SO_ACCEPTFILTER, $accf_arg;
+			CORE::setsockopt $s, SOL_SOCKET, $SO_ACCEPTFILTER,
+					pack('a16a240', $af_name, '') or
+				warn 'W: ', sockname($s), <<EOM;
+ SO_ACCEPTFILTER $af_name: $! (try `kldload $af_name')
+EOM
 		}
 	};
 	my $err = $@; # sockname() clobbers $@
diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index b863ad6..0f5b107 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -30,7 +30,7 @@
 		create_coderepo require_bsd kernel_version check_broken_tmpfs
 		quit_waiter_pipe wait_for_eof require_git_http_backend
 		tcp_host_port test_lei lei lei_ok $lei_out $lei_err $lei_opt
-		test_httpd xbail require_cmd is_xdeeply tail_f
+		test_httpd no_httpd_errors xbail require_cmd is_xdeeply tail_f
 		ignore_inline_c_missing no_pollerfd no_coredump cfg_new
 		strace strace_inject lsof_pid oct_is);
 	require Test::More;
@@ -948,6 +948,16 @@
 	$ibx;
 }
 
+sub no_httpd_errors ($;$) {
+	my ($err, $msg) = @_;
+	open my $fh, '<', $err;
+	my $e = read_all $fh;
+	$e =~ s/^Plack::Middleware::ReverseProxy missing,\n//gms and
+		$e =~ s/^URL generation for redirects[^\n]*\n//gms;
+	$e =~ s/^W: .*?try `kldload[^\n]+\n//gms;
+	is $e, '', $msg // 'no httpd errors';
+}
+
 sub test_httpd ($$;$$) {
 	my ($env, $client, $skip, $cb) = @_;
 	my ($tmpdir, $for_destroy);
@@ -976,12 +986,7 @@
 							ua => $ua);
 		$cb->() if $cb;
 		$td->join('TERM');
-		open my $fh, '<', $err;
-		my $e = read_all($fh);
-		if ($e =~ s/^Plack::Middleware::ReverseProxy missing,\n//gms) {
-			$e =~ s/^URL generation for redirects .*\n//gms;
-		}
-		is($e, '', 'no errors');
+		no_httpd_errors $err;
 	}
 };
 
diff --git a/t/solver_git.t b/t/solver_git.t
index cebcf47..c45011a 100644
--- a/t/solver_git.t
+++ b/t/solver_git.t
@@ -43,11 +43,8 @@
 my $expect = '69df7d565d49fbaaeb0a067910f03dc22cd52bd0';
 my $non_existent = 'ee5e32211bf62ab6531bdf39b84b6920d0b6775a';
 my $stderr_empty = sub {
-	my ($msg) = @_;
-	open my $efh, '<', "$tmpdir/stderr.log";
-	my @l = <$efh>;
-	@l = grep(!/reverse ?proxy/i, @l);
-	is_xdeeply(\@l, [], $msg // 'stderr.log is empty');
+	no_httpd_errors "$tmpdir/stderr.log",
+		$_[0] // 'stderr.log is empty';
 };
 
 test_lei({tmpdir => "$tmpdir/blob"}, sub {