diff --git a/hw/pc.h b/hw/pc.h
index fbcf43d71763..da1b102ef1e0 100644
--- a/hw/pc.h
+++ b/hw/pc.h
@@ -187,4 +187,35 @@ void pc_system_firmware_init(MemoryRegion *rom_memory);
 
 int e820_add_entry(uint64_t, uint64_t, uint32_t);
 
+#define PC_COMPAT_1_4 \
+        {\
+            .driver   = "scsi-hd",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "scsi-cd",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "scsi-disk",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "ide-hd",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "ide-cd",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "ide-drive",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	},{\
+            .driver   = "virtio-blk-pci",\
+            .property = "discard_granularity",\
+            .value    = stringify(0),\
+	}
+
 #endif
diff --git a/hw/pc_piix.c b/hw/pc_piix.c
index 0af436cfaf6e..aa9cc81a2d5d 100644
--- a/hw/pc_piix.c
+++ b/hw/pc_piix.c
@@ -294,8 +294,8 @@ static void pc_xen_hvm_init(QEMUMachineInitArgs *args)
 }
 #endif
 
-static QEMUMachine pc_i440fx_machine_v1_4 = {
-    .name = "pc-i440fx-1.4",
+static QEMUMachine pc_i440fx_machine_v1_5 = {
+    .name = "pc-i440fx-1.5",
     .alias = "pc",
     .desc = "Standard PC (i440FX + PIIX, 1996)",
     .init = pc_init_pci,
@@ -304,7 +304,20 @@ static QEMUMachine pc_i440fx_machine_v1_4 = {
     DEFAULT_MACHINE_OPTIONS,
 };
 
+static QEMUMachine pc_i440fx_machine_v1_4 = {
+    .name = "pc-i440fx-1.4",
+    .desc = "Standard PC (i440FX + PIIX, 1996)",
+    .init = pc_init_pci,
+    .max_cpus = 255,
+    .compat_props = (GlobalProperty[]) {
+        PC_COMPAT_1_4,
+        { /* end of list */ }
+    },
+    DEFAULT_MACHINE_OPTIONS,
+};
+
 #define PC_COMPAT_1_3 \
+	PC_COMPAT_1_4, \
         {\
             .driver   = "usb-tablet",\
             .property = "usb_version",\
@@ -679,6 +692,7 @@ static QEMUMachine xenfv_machine = {
 
 static void pc_machine_init(void)
 {
+    qemu_register_machine(&pc_i440fx_machine_v1_5);
     qemu_register_machine(&pc_i440fx_machine_v1_4);
     qemu_register_machine(&pc_machine_v1_3);
     qemu_register_machine(&pc_machine_v1_2);
diff --git a/hw/pc_q35.c b/hw/pc_q35.c
index 6f5ff8dcae27..e22fb9891d17 100644
--- a/hw/pc_q35.c
+++ b/hw/pc_q35.c
@@ -209,8 +209,8 @@ static void pc_q35_init(QEMUMachineInitArgs *args)
     }
 }
 
-static QEMUMachine pc_q35_machine = {
-    .name = "pc-q35-1.4",
+static QEMUMachine pc_q35_machine_v1_5 = {
+    .name = "pc-q35-1.5",
     .alias = "q35",
     .desc = "Standard PC (Q35 + ICH9, 2009)",
     .init = pc_q35_init,
@@ -218,9 +218,22 @@ static QEMUMachine pc_q35_machine = {
     DEFAULT_MACHINE_OPTIONS,
 };
 
+static QEMUMachine pc_q35_machine_v1_4 = {
+    .name = "pc-q35-1.4",
+    .desc = "Standard PC (Q35 + ICH9, 2009)",
+    .init = pc_q35_init,
+    .max_cpus = 255,
+    .compat_props = (GlobalProperty[]) {
+        PC_COMPAT_1_4,
+        { /* end of list */ }
+    },
+    DEFAULT_MACHINE_OPTIONS,
+};
+
 static void pc_q35_machine_init(void)
 {
-    qemu_register_machine(&pc_q35_machine);
+    qemu_register_machine(&pc_q35_machine_v1_5);
+    qemu_register_machine(&pc_q35_machine_v1_4);
 }
 
 machine_init(pc_q35_machine_init);