diff --git a/hw/sun4m.c b/hw/sun4m.c
index b2d4cfa08994288d9e0f029f423a90a2eb52c13f..25f6c1e72e05dfaca02c29af19959d45397277ce 100644
--- a/hw/sun4m.c
+++ b/hw/sun4m.c
@@ -1100,7 +1100,6 @@ QEMUMachine ss5_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 QEMUMachine ss10_machine = {
@@ -1110,7 +1109,7 @@ QEMUMachine ss10_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
+    .max_cpus = 4,
 };
 
 QEMUMachine ss600mp_machine = {
@@ -1120,7 +1119,7 @@ QEMUMachine ss600mp_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
+    .max_cpus = 4,
 };
 
 QEMUMachine ss20_machine = {
@@ -1130,7 +1129,7 @@ QEMUMachine ss20_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
+    .max_cpus = 4,
 };
 
 QEMUMachine voyager_machine = {
@@ -1140,7 +1139,6 @@ QEMUMachine voyager_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 QEMUMachine ss_lx_machine = {
@@ -1150,7 +1148,6 @@ QEMUMachine ss_lx_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 QEMUMachine ss4_machine = {
@@ -1160,7 +1157,6 @@ QEMUMachine ss4_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 QEMUMachine scls_machine = {
@@ -1170,7 +1166,6 @@ QEMUMachine scls_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 QEMUMachine sbook_machine = {
@@ -1180,7 +1175,6 @@ QEMUMachine sbook_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
 static const struct sun4d_hwdef sun4d_hwdefs[] = {
@@ -1429,7 +1423,7 @@ QEMUMachine ss1000_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
+    .max_cpus = 8,
 };
 
 QEMUMachine ss2000_machine = {
@@ -1439,7 +1433,7 @@ QEMUMachine ss2000_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
+    .max_cpus = 20,
 };
 
 static const struct sun4c_hwdef sun4c_hwdefs[] = {
@@ -1643,6 +1637,5 @@ QEMUMachine ss2_machine = {
     .ram_require = PROM_SIZE_MAX + TCX_SIZE,
     .nodisk_ok = 1,
     .use_scsi = 1,
-    .max_cpus = 16,
 };
 
diff --git a/hw/sun4u.c b/hw/sun4u.c
index 057d598d7f5acf46ad606ff42c46487accbef8dc..057e78fc4929a3fb37efb96e05e793667e746b7d 100644
--- a/hw/sun4u.c
+++ b/hw/sun4u.c
@@ -588,7 +588,7 @@ QEMUMachine sun4u_machine = {
     .init = sun4u_init,
     .ram_require = PROM_SIZE_MAX + VGA_RAM_SIZE,
     .nodisk_ok = 1,
-    .max_cpus = 16,
+    .max_cpus = 1, // XXX for now
 };
 
 QEMUMachine sun4v_machine = {
@@ -597,7 +597,7 @@ QEMUMachine sun4v_machine = {
     .init = sun4v_init,
     .ram_require = PROM_SIZE_MAX + VGA_RAM_SIZE,
     .nodisk_ok = 1,
-    .max_cpus = 16,
+    .max_cpus = 1, // XXX for now
 };
 
 QEMUMachine niagara_machine = {
@@ -606,5 +606,5 @@ QEMUMachine niagara_machine = {
     .init = niagara_init,
     .ram_require = PROM_SIZE_MAX + VGA_RAM_SIZE,
     .nodisk_ok = 1,
-    .max_cpus = 16,
+    .max_cpus = 1, // XXX for now
 };