diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c
index cfc1687473fe..2e35e9eb491c 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/txg.c
@@ -43,7 +43,7 @@ int zfs_txg_timeout = 5;	/* max seconds worth of delta per txg */
 SYSCTL_DECL(_vfs_zfs);
 SYSCTL_NODE(_vfs_zfs, OID_AUTO, txg, CTLFLAG_RW, 0, "ZFS TXG");
 TUNABLE_INT("vfs.zfs.txg.timeout", &zfs_txg_timeout);
-SYSCTL_INT(_vfs_zfs_txg, OID_AUTO, timeout, CTLFLAG_RDTUN, &zfs_txg_timeout, 0,
+SYSCTL_INT(_vfs_zfs_txg, OID_AUTO, timeout, CTLFLAG_RW, &zfs_txg_timeout, 0,
     "Maximum seconds worth of delta per txg");
 
 /*