diff --git a/scst/include/scst.h b/scst/include/scst.h
index e4886e843..5daaa8fcb 100644
--- a/scst/include/scst.h
+++ b/scst/include/scst.h
@@ -3863,6 +3863,11 @@ static inline int scst_get_out_buf_count(struct scst_cmd *cmd)
 int scst_get_buf_full(struct scst_cmd *cmd, uint8_t **buf);
 void scst_put_buf_full(struct scst_cmd *cmd, uint8_t *buf);
 
+static inline gfp_t scst_cmd_get_gfp_flags(struct scst_cmd *cmd)
+{
+	return cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL;
+}
+
 #if LINUX_VERSION_CODE < KERNEL_VERSION(2, 6, 23) && !defined(BACKPORT_LINUX_WORKQUEUE_TO_2_6_19)
 #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 20))
 static inline int cancel_delayed_work_sync(struct delayed_work *work)
diff --git a/scst/src/dev_handlers/scst_vdisk.c b/scst/src/dev_handlers/scst_vdisk.c
index bc76e8b26..457191282 100644
--- a/scst/src/dev_handlers/scst_vdisk.c
+++ b/scst/src/dev_handlers/scst_vdisk.c
@@ -228,7 +228,8 @@ static void vdisk_exec_read_toc(struct scst_cmd *cmd);
 static void vdisk_exec_prevent_allow_medium_removal(struct scst_cmd *cmd);
 static void vdisk_exec_unmap(struct scst_cmd *cmd, struct scst_vdisk_thr *thr);
 static int vdisk_fsync(struct scst_vdisk_thr *thr, loff_t loff,
-	loff_t len, struct scst_cmd *cmd, struct scst_device *dev);
+	loff_t len, struct scst_device *dev, gfp_t gfp_flags,
+	struct scst_cmd *cmd);
 #ifdef CONFIG_SCST_PROC
 static int vdisk_read_proc(struct seq_file *seq,
 	struct scst_dev_type *dev_type);
@@ -957,7 +958,7 @@ static int vdisk_do_job(struct scst_cmd *cmd)
 		d = scst_find_thr_data(tgt_dev);
 		if (unlikely(d == NULL)) {
 			thr = vdisk_init_thr_data(tgt_dev,
-				cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL);
+					scst_cmd_get_gfp_flags(cmd));
 			if (thr == NULL) {
 				scst_set_busy(cmd);
 				goto out_compl;
@@ -1074,7 +1075,8 @@ static int vdisk_do_job(struct scst_cmd *cmd)
 			vdisk_exec_write(cmd, thr, loff);
 		/* O_SYNC flag is used for WT devices */
 		if (fua)
-			vdisk_fsync(thr, loff, data_len, cmd, dev);
+			vdisk_fsync(thr, loff, data_len, dev,
+				scst_cmd_get_gfp_flags(cmd), cmd);
 		break;
 	}
 	case WRITE_VERIFY:
@@ -1082,6 +1084,8 @@ static int vdisk_do_job(struct scst_cmd *cmd)
 	case WRITE_VERIFY_16:
 	{
 		/* ToDo: BLOCKIO VERIFY */
+		if (virt_dev->blockio)
+			goto out_invalid_opcode;
 		vdisk_exec_write(cmd, thr, loff);
 		/* O_SYNC flag is used for WT devices */
 		if (scsi_status_is_good(cmd->status))
@@ -1100,12 +1104,14 @@ static int vdisk_do_job(struct scst_cmd *cmd)
 			cmd->completed = 1;
 			cmd->scst_cmd_done(cmd, SCST_CMD_STATE_DEFAULT,
 				SCST_CONTEXT_SAME);
-			vdisk_fsync(thr, loff, data_len, NULL, dev);
+			vdisk_fsync(thr, loff, data_len, dev,
+				scst_cmd_get_gfp_flags(cmd), NULL);
 			/* ToDo: vdisk_fsync() error processing */
 			scst_cmd_put(cmd);
 			goto out_thr;
 		} else {
-			vdisk_fsync(thr, loff, data_len, cmd, dev);
+			vdisk_fsync(thr, loff, data_len, dev,
+				scst_cmd_get_gfp_flags(cmd), cmd);
 			break;
 		}
 	}
@@ -1134,7 +1140,8 @@ static int vdisk_do_job(struct scst_cmd *cmd)
 		vdisk_exec_read_toc(cmd);
 		break;
 	case START_STOP:
-		vdisk_fsync(thr, 0, virt_dev->file_size, cmd, dev);
+		vdisk_fsync(thr, 0, virt_dev->file_size, dev,
+			scst_cmd_get_gfp_flags(cmd), cmd);
 		break;
 	case RESERVE:
 	case RESERVE_10:
@@ -1353,7 +1360,7 @@ static void vdisk_exec_unmap(struct scst_cmd *cmd, struct scst_vdisk_thr *thr)
 
 		if (virt_dev->blockio) {
 #if LINUX_VERSION_CODE > KERNEL_VERSION(2, 6, 27)
-			gfp_t gfp = cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL;
+			gfp_t gfp = scst_cmd_get_gfp_flags(cmd);
 #if LINUX_VERSION_CODE <= KERNEL_VERSION(2, 6, 31)
 			err = blkdev_issue_discard(inode->i_bdev, start, len,
 					gfp);
@@ -2633,7 +2640,8 @@ static void vdisk_exec_prevent_allow_medium_removal(struct scst_cmd *cmd)
 }
 
 static int vdisk_fsync(struct scst_vdisk_thr *thr, loff_t loff,
-	loff_t len, struct scst_cmd *cmd, struct scst_device *dev)
+	loff_t len, struct scst_device *dev, gfp_t gfp_flags,
+	struct scst_cmd *cmd)
 {
 	int res = 0;
 	struct scst_vdisk_dev *virt_dev = dev->dh_priv;
@@ -2641,14 +2649,18 @@ static int vdisk_fsync(struct scst_vdisk_thr *thr, loff_t loff,
 
 	TRACE_ENTRY();
 
-	/* Hopefully, the compiler will generate the single comparison */
+	/**
+	 ** !!! CAUTION !!!: cmd can be NULL here! Don't use it for
+	 ** anything without checking for NULL at first !!!
+	 **/
+
+	/* It should be generated by compiler as a single comparison */
 	if (virt_dev->nv_cache || virt_dev->wt_flag ||
 	    virt_dev->o_direct_flag || virt_dev->nullio)
 		goto out;
 
 	if (virt_dev->blockio) {
-		res = vdisk_blockio_flush(thr->bdev,
-			(cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL), true);
+		res = vdisk_blockio_flush(thr->bdev, gfp_flags, true);
 		goto out;
 	}
 
@@ -3043,7 +3055,7 @@ static void blockio_exec_rw(struct scst_cmd *cmd, struct scst_vdisk_thr *thr,
 	int need_new_bio;
 	struct scst_blockio_work *blockio_work;
 	int bios = 0;
-	gfp_t gfp_mask = (cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL);
+	gfp_t gfp_mask = scst_cmd_get_gfp_flags(cmd);
 #if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 39)
 	struct blk_plug plug;
 #endif
@@ -3229,14 +3241,17 @@ static void vdisk_exec_verify(struct scst_cmd *cmd,
 
 	TRACE_ENTRY();
 
-	if (vdisk_fsync(thr, loff, cmd->bufflen, cmd, cmd->dev) != 0)
+	sBUG_ON(virt_dev->blockio);
+
+	if (vdisk_fsync(thr, loff, cmd->bufflen, cmd->dev,
+			scst_cmd_get_gfp_flags(cmd), cmd) != 0)
 		goto out;
 
 	/*
 	 * Until the cache is cleared prior the verifying, there is not
 	 * much point in this code. ToDo.
 	 *
-	 * Nevertherless, this code is valuable if the data have not read
+	 * Nevertherless, this code is valuable if the data have not been read
 	 * from the file/disk yet.
 	 */
 
diff --git a/scst/src/scst_lib.c b/scst/src/scst_lib.c
index e9c70bb1b..1330caa71 100644
--- a/scst/src/scst_lib.c
+++ b/scst/src/scst_lib.c
@@ -4736,7 +4736,7 @@ int scst_scsi_exec_async(struct scst_cmd *cmd, void *data,
 	struct request *rq;
 	struct scsi_io_context *sioc;
 	int write = (cmd->data_direction & SCST_DATA_WRITE) ? WRITE : READ;
-	gfp_t gfp = cmd->noio_mem_alloc ? GFP_NOIO : GFP_KERNEL;
+	gfp_t gfp = scst_cmd_get_gfp_flags(cmd);
 	int cmd_len = cmd->cdb_len;
 
 	sioc = kmem_cache_zalloc(scsi_io_context_cache, gfp);