diff --git a/sys/dev/arcmsr/arcmsr.c b/sys/dev/arcmsr/arcmsr.c
index 16fe5ee959e6..375f1f114d13 100644
--- a/sys/dev/arcmsr/arcmsr.c
+++ b/sys/dev/arcmsr/arcmsr.c
@@ -83,6 +83,8 @@
 ** 1.40.00.01   10/30/2017  Ching Huang     Fixed release memory resource
 ** 1.50.00.00   09/30/2020  Ching Huang     Added support ARC-1886, NVMe/SAS/SATA controller
 ** 1.50.00.01   02/26/2021  Ching Huang     Fixed no action of hot plugging device on type_F adapter
+** 1.50.00.02   04/16/2021  Ching Huang     Fixed scsi command timeout on ARC-1886 when
+**                                          scatter-gather count large than some number
 ******************************************************************************************
 */
 
@@ -140,7 +142,7 @@ __FBSDID("$FreeBSD$");
 
 #define arcmsr_callout_init(a)	callout_init(a, /*mpsafe*/1);
 
-#define ARCMSR_DRIVER_VERSION	"arcmsr version 1.50.00.01 2021-02-26"
+#define ARCMSR_DRIVER_VERSION	"arcmsr version 1.50.00.02 2021-04-16"
 #include <dev/arcmsr/arcmsr.h>
 /*
 **************************************************************************
@@ -1183,8 +1185,12 @@ static void arcmsr_post_srb(struct AdapterControlBlock *acb, struct CommandContr
 
 			if (srb->arc_cdb_size <= 0x300)
 				arc_cdb_size = (srb->arc_cdb_size - 1) >> 6 | 1;
-			else
-				arc_cdb_size = (((srb->arc_cdb_size + 0xff) >> 8) + 2) << 1 | 1;
+			else {
+				arc_cdb_size = ((srb->arc_cdb_size + 0xff) >> 8) + 2;
+				if (arc_cdb_size > 0xF)
+					arc_cdb_size = 0xF;
+				arc_cdb_size = (arc_cdb_size << 1) | 1;
+			}
 			ccb_post_stamp = (srb->smid | arc_cdb_size);
 			CHIP_REG_WRITE32(HBF_MessageUnit, 0, inbound_queueport_high, 0);
 			CHIP_REG_WRITE32(HBF_MessageUnit, 0, inbound_queueport_low, ccb_post_stamp);