diff --git a/iscsi-scst/kernel/config.c b/iscsi-scst/kernel/config.c
index b4c7e842e..3c2d9f425 100644
--- a/iscsi-scst/kernel/config.c
+++ b/iscsi-scst/kernel/config.c
@@ -1095,7 +1095,7 @@ out:
 	return res;
 }
 
-static long ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+static long iscsi_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	long err;
 
@@ -1172,7 +1172,7 @@ out:
 	return err;
 }
 
-static int open(struct inode *inode, struct file *file)
+static int iscsi_open(struct inode *inode, struct file *file)
 {
 	bool already;
 
@@ -1190,7 +1190,7 @@ static int open(struct inode *inode, struct file *file)
 		return 0;
 }
 
-static int release(struct inode *inode, struct file *filp)
+static int iscsi_release(struct inode *inode, struct file *filp)
 {
 #ifndef CONFIG_SCST_PROC
 	struct iscsi_attr *attr, *t;
@@ -1222,10 +1222,10 @@ static int release(struct inode *inode, struct file *filp)
 
 const struct file_operations ctr_fops = {
 	.owner		= THIS_MODULE,
-	.unlocked_ioctl	= ioctl,
-	.compat_ioctl	= ioctl,
-	.open		= open,
-	.release	= release,
+	.unlocked_ioctl	= iscsi_ioctl,
+	.compat_ioctl	= iscsi_ioctl,
+	.open		= iscsi_open,
+	.release	= iscsi_release,
 };
 
 #ifdef CONFIG_SCST_DEBUG
diff --git a/iscsi-scst/kernel/conn.c b/iscsi-scst/kernel/conn.c
index e713a1e43..572d6c440 100644
--- a/iscsi-scst/kernel/conn.c
+++ b/iscsi-scst/kernel/conn.c
@@ -397,7 +397,7 @@ struct iscsi_conn *conn_lookup(struct iscsi_session *session, u16 cid)
 	 */
 	list_for_each_entry_reverse(conn, &session->conn_list,
 					conn_list_entry) {
-		if (conn->cid == cid)
+		if (conn->cid == cid && !conn->closing)
 			return conn;
 	}
 	return NULL;
diff --git a/iscsi-scst/kernel/iscsi.c b/iscsi-scst/kernel/iscsi.c
index 1a5ac0991..54205077f 100644
--- a/iscsi-scst/kernel/iscsi.c
+++ b/iscsi-scst/kernel/iscsi.c
@@ -2154,6 +2154,9 @@ static int scsi_cmnd_start(struct iscsi_cmnd *req)
 	req->scst_state = ISCSI_CMD_STATE_RX_CMD;
 	conn->rx_task = current;
 	scst_cmd_init_stage1_done(scst_cmd, SCST_CONTEXT_DIRECT, 0);
+#ifdef CONFIG_SCST_EXTRACHECKS
+	conn->rx_task = NULL;
+#endif
 
 	if (req->scst_state != ISCSI_CMD_STATE_RX_CMD)
 		res = req->conn->transport->iscsit_receive_cmnd_data(req);
@@ -4237,7 +4240,7 @@ create:
 	if (p == NULL) {
 		PRINT_ERROR("Unable to allocate iSCSI thread pool (size %zd)",
 			sizeof(*p));
-		res = -ENOMEM;
+		res = 0;
 		if (!list_empty(&iscsi_thread_pools_list)) {
 			PRINT_WARNING("%s", "Using global iSCSI thread pool "
 				"instead");
diff --git a/iscsi-scst/usr/event.c b/iscsi-scst/usr/event.c
index 8d0734767..1d28ef9e9 100644
--- a/iscsi-scst/usr/event.c
+++ b/iscsi-scst/usr/event.c
@@ -1066,6 +1066,15 @@ retry:
 			goto retry;
 		log_error("read netlink fd (%d) failed: %s", fd, strerror(errno));
 		exit(1);
+	} else if (rc == 0) {
+		/*
+		 * EOF on nl_fd --
+		 * We arrive here after the kernel module closes the other end
+		 * of nl_fd during shutdown of the kernel modules.  The daemon
+		 * thread is expected to exit when this happens.
+		 */
+		log_info("kernel module shutdown -- daemon exits");
+		exit(1);
 	}
 
 	log_debug(1, "target %u, session %#" PRIx64 ", conn %u, code %u, cookie %d",
diff --git a/iscsi-scst/usr/iscsi_scstd.c b/iscsi-scst/usr/iscsi_scstd.c
index 7fa813d04..d66943087 100644
--- a/iscsi-scst/usr/iscsi_scstd.c
+++ b/iscsi-scst/usr/iscsi_scstd.c
@@ -846,8 +846,13 @@ int main(int argc, char **argv)
 	/*
 	 * Otherwise we could die in some later write() during the event_loop()
 	 * instead of getting EPIPE!
+	 *
+	 * The effects of signal(2) in a multithreaded process are unspecified,
+	 * so use sigaction(2) instead.
 	 */
-	signal(SIGPIPE, SIG_IGN);
+	struct sigaction act = (struct sigaction) { .sa_handler = SIG_IGN };
+	int rc = sigaction(SIGPIPE, &act, NULL);
+	assert(rc == 0);
 
 	while ((ch = getopt_long(argc, argv, "c:fd:s:u:g:a:p:vh", long_options, &longindex)) >= 0) {
 		switch (ch) {
diff --git a/scst/src/dev_handlers/scst_vdisk.c b/scst/src/dev_handlers/scst_vdisk.c
index 19cddff2e..2e2c4caf4 100644
--- a/scst/src/dev_handlers/scst_vdisk.c
+++ b/scst/src/dev_handlers/scst_vdisk.c
@@ -1700,6 +1700,11 @@ next:
 
 	dev->dev_rd_only = virt_dev->rd_only;
 
+#ifdef CONFIG_SCST_PROC
+	if (virt_dev->nullio && !virt_dev->file_size)
+		virt_dev->file_size = VDISK_NULLIO_SIZE;
+#endif
+
 	res = vdisk_reexamine(virt_dev);
 	if (res < 0)
 		goto out;
diff --git a/usr/fileio/common.c b/usr/fileio/common.c
index d40caafbf..636b0a707 100644
--- a/usr/fileio/common.c
+++ b/usr/fileio/common.c
@@ -747,7 +747,7 @@ static int process_cmd(struct vdisk_cmd *vcmd)
 
 	case SCST_USER_TASK_MGMT_DONE:
 		res = do_tm(vcmd, 1);
-#if DEBUG_TM_FN_IGNORE
+#ifdef DEBUG_TM_FN_IGNORE
 		if (dev->debug_tm_ignore) {
 			sleep(15);
 		}