diff --git a/libc/SECCOMP_ALLOWLIST_COMMON.TXT b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
index 20c1441..6650d7e 100644
--- a/libc/SECCOMP_ALLOWLIST_COMMON.TXT
+++ b/libc/SECCOMP_ALLOWLIST_COMMON.TXT
@@ -72,3 +72,5 @@
 int rt_sigtimedwait_time64(const sigset64_t*, siginfo_t*, const timespec64*, size_t) lp32
 int futex_time64(int*, int, int, const timespec64*, int*, int) lp32
 int sched_rr_get_interval_time64(pid_t, timespec64*) lp32
+# Since Linux 5.4, not in glibc. Probed for and conditionally used by ART.
+int userfaultfd(int) all