diff --git a/sys/fs/nfs/nfs_commonport.c b/sys/fs/nfs/nfs_commonport.c
index f08f7f1186a..c2ea3331c28 100644
--- a/sys/fs/nfs/nfs_commonport.c
+++ b/sys/fs/nfs/nfs_commonport.c
@@ -90,7 +90,7 @@ SYSCTL_INT(_vfs_nfs, OID_AUTO, debuglevel, CTLFLAG_RW, &nfscl_debuglevel,
     0, "Debug level for NFS client");
 SYSCTL_INT(_vfs_nfs, OID_AUTO, userhashsize, CTLFLAG_RDTUN, &nfsrv_lughashsize,
     0, "Size of hash tables for uid/name mapping");
-int nfs_pnfsiothreads = 0;
+int nfs_pnfsiothreads = -1;
 SYSCTL_INT(_vfs_nfs, OID_AUTO, pnfsiothreads, CTLFLAG_RW, &nfs_pnfsiothreads,
     0, "Number of pNFS mirror I/O threads");
 
@@ -723,6 +723,8 @@ nfs_pnfsio(task_fn_t *func, void *context)
 	pio = (struct pnfsio *)context;
 	if (pnfsioq == NULL) {
 		if (nfs_pnfsiothreads == 0)
+			return (EPERM);
+		if (nfs_pnfsiothreads < 0)
 			nfs_pnfsiothreads = mp_ncpus * 4;
 		pnfsioq = taskqueue_create("pnfsioq", M_WAITOK,
 		    taskqueue_thread_enqueue, &pnfsioq);
diff --git a/sys/fs/nfsclient/nfs_clrpcops.c b/sys/fs/nfsclient/nfs_clrpcops.c
index c671955e43d..d1420e56413 100644
--- a/sys/fs/nfsclient/nfs_clrpcops.c
+++ b/sys/fs/nfsclient/nfs_clrpcops.c
@@ -6436,7 +6436,7 @@ nfsio_writedsmir(vnode_t vp, int *iomode, int *must_commit,
 	drpc->p = p;
 	drpc->inprog = 0;
 	ret = EIO;
-	if (nfs_pnfsiothreads > 0) {
+	if (nfs_pnfsiothreads != 0) {
 		ret = nfs_pnfsio(start_writedsmir, drpc);
 		NFSCL_DEBUG(4, "nfsio_writedsmir: nfs_pnfsio=%d\n", ret);
 	}
@@ -6615,7 +6615,7 @@ nfsio_commitds(vnode_t vp, uint64_t offset, int cnt, struct nfsclds *dsp,
 	drpc->p = p;
 	drpc->inprog = 0;
 	ret = EIO;
-	if (nfs_pnfsiothreads > 0) {
+	if (nfs_pnfsiothreads != 0) {
 		ret = nfs_pnfsio(start_commitds, drpc);
 		NFSCL_DEBUG(4, "nfsio_commitds: nfs_pnfsio=%d\n", ret);
 	}