diff --git a/drivers/scsi/atari_scsi.c b/drivers/scsi/atari_scsi.c
index 89f5154c40b6..764c46d7333e 100644
--- a/drivers/scsi/atari_scsi.c
+++ b/drivers/scsi/atari_scsi.c
@@ -742,7 +742,7 @@ static int __init atari_scsi_probe(struct platform_device *pdev)
 		atari_scsi_template.sg_tablesize = SG_ALL;
 	} else {
 		atari_scsi_template.can_queue    = 1;
-		atari_scsi_template.sg_tablesize = SG_NONE;
+		atari_scsi_template.sg_tablesize = 1;
 	}
 
 	if (setup_can_queue > 0)
@@ -751,8 +751,8 @@ static int __init atari_scsi_probe(struct platform_device *pdev)
 	if (setup_cmd_per_lun > 0)
 		atari_scsi_template.cmd_per_lun = setup_cmd_per_lun;
 
-	/* Leave sg_tablesize at 0 on a Falcon! */
-	if (ATARIHW_PRESENT(TT_SCSI) && setup_sg_tablesize >= 0)
+	/* Don't increase sg_tablesize on Falcon! */
+	if (ATARIHW_PRESENT(TT_SCSI) && setup_sg_tablesize > 0)
 		atari_scsi_template.sg_tablesize = setup_sg_tablesize;
 
 	if (setup_hostid >= 0) {
diff --git a/drivers/scsi/mac_scsi.c b/drivers/scsi/mac_scsi.c
index 643321fc152d..b5050c2ede00 100644
--- a/drivers/scsi/mac_scsi.c
+++ b/drivers/scsi/mac_scsi.c
@@ -429,7 +429,7 @@ static int __init mac_scsi_probe(struct platform_device *pdev)
 		mac_scsi_template.can_queue = setup_can_queue;
 	if (setup_cmd_per_lun > 0)
 		mac_scsi_template.cmd_per_lun = setup_cmd_per_lun;
-	if (setup_sg_tablesize >= 0)
+	if (setup_sg_tablesize > 0)
 		mac_scsi_template.sg_tablesize = setup_sg_tablesize;
 	if (setup_hostid >= 0)
 		mac_scsi_template.this_id = setup_hostid & 7;
diff --git a/drivers/scsi/sun3_scsi.c b/drivers/scsi/sun3_scsi.c
index 9492638296c8..af8a7ef9c858 100644
--- a/drivers/scsi/sun3_scsi.c
+++ b/drivers/scsi/sun3_scsi.c
@@ -498,7 +498,7 @@ static struct scsi_host_template sun3_scsi_template = {
 	.eh_host_reset_handler	= sun3scsi_host_reset,
 	.can_queue		= 16,
 	.this_id		= 7,
-	.sg_tablesize		= SG_NONE,
+	.sg_tablesize		= 1,
 	.cmd_per_lun		= 2,
 	.use_clustering		= DISABLE_CLUSTERING,
 	.cmd_size		= NCR5380_CMD_SIZE,
@@ -520,7 +520,7 @@ static int __init sun3_scsi_probe(struct platform_device *pdev)
 		sun3_scsi_template.can_queue = setup_can_queue;
 	if (setup_cmd_per_lun > 0)
 		sun3_scsi_template.cmd_per_lun = setup_cmd_per_lun;
-	if (setup_sg_tablesize >= 0)
+	if (setup_sg_tablesize > 0)
 		sun3_scsi_template.sg_tablesize = setup_sg_tablesize;
 	if (setup_hostid >= 0)
 		sun3_scsi_template.this_id = setup_hostid & 7;