diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 680ba180a672..9456b284683f 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -352,7 +352,6 @@ struct sdebug_dev_info {
 	bool zoned;
 	unsigned int zcap;
 	unsigned int zsize;
-	unsigned int zsize_shift;
 	unsigned int nr_zones;
 	unsigned int nr_conv_zones;
 	unsigned int nr_seq_zones;
@@ -3146,7 +3145,7 @@ static inline bool sdebug_dev_is_zoned(struct sdebug_dev_info *devip)
 static struct sdeb_zone_state *zbc_zone(struct sdebug_dev_info *devip,
 					unsigned long long lba)
 {
-	u32 zno = lba >> devip->zsize_shift;
+	u32 zno = div_u64(lba, devip->zsize);
 	struct sdeb_zone_state *zsp;
 
 	if (devip->zcap == devip->zsize || zno < devip->nr_conv_zones)
@@ -5695,6 +5694,14 @@ static void sdebug_q_cmd_wq_complete(struct work_struct *work)
 static bool got_shared_uuid;
 static uuid_t shared_uuid;
 
+static bool sdebug_is_zone_start(struct sdebug_dev_info *devip, u64 zstart)
+{
+	u32 remainder;
+
+	div_u64_rem(zstart, devip->zsize, &remainder);
+	return remainder == 0;
+}
+
 static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 {
 	struct sdeb_zone_state *zsp;
@@ -5719,10 +5726,6 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 			return -EINVAL;
 		}
 	} else {
-		if (!is_power_of_2(sdeb_zbc_zone_size_mb)) {
-			pr_err("Zone size is not a power of 2\n");
-			return -EINVAL;
-		}
 		devip->zsize = (sdeb_zbc_zone_size_mb * SZ_1M)
 			>> ilog2(sdebug_sector_size);
 		if (devip->zsize >= capacity) {
@@ -5731,8 +5734,7 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 		}
 	}
 
-	devip->zsize_shift = ilog2(devip->zsize);
-	devip->nr_zones = (capacity + devip->zsize - 1) >> devip->zsize_shift;
+	devip->nr_zones = div_u64(capacity + devip->zsize - 1, devip->zsize);
 
 	if (sdeb_zbc_zone_cap_mb == 0) {
 		devip->zcap = devip->zsize;
@@ -5745,14 +5747,14 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 		}
 	}
 
-	conv_capacity = (sector_t)sdeb_zbc_nr_conv << devip->zsize_shift;
+	conv_capacity = (sector_t)sdeb_zbc_nr_conv * devip->zsize;
 	if (conv_capacity >= capacity) {
 		pr_err("Number of conventional zones too large\n");
 		return -EINVAL;
 	}
 	devip->nr_conv_zones = sdeb_zbc_nr_conv;
-	devip->nr_seq_zones = ALIGN(capacity - conv_capacity, devip->zsize) >>
-			      devip->zsize_shift;
+	devip->nr_seq_zones = div_u64(capacity - conv_capacity +
+				      devip->zsize - 1, devip->zsize);
 	devip->nr_zones = devip->nr_conv_zones + devip->nr_seq_zones;
 
 	/* Add gap zones if zone capacity is smaller than the zone size */
@@ -5783,7 +5785,7 @@ static int sdebug_device_create_zones(struct sdebug_dev_info *devip)
 			zsp->z_wp = (sector_t)-1;
 			zsp->z_size =
 				min_t(u64, devip->zsize, capacity - zstart);
-		} else if ((zstart & (devip->zsize - 1)) == 0) {
+		} else if (sdebug_is_zone_start(devip, zstart)) {
 			if (devip->zoned)
 				zsp->z_type = ZBC_ZTYPE_SWR;
 			else