diff --git a/hw/riscv/sifive_u.c b/hw/riscv/sifive_u.c
index 6116c38..25df16c 100644
--- a/hw/riscv/sifive_u.c
+++ b/hw/riscv/sifive_u.c
@@ -223,7 +223,7 @@ static void riscv_sifive_u_init(MachineState *machine)
     SiFiveUState *s = g_new0(SiFiveUState, 1);
     MemoryRegion *sys_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
-    MemoryRegion *boot_rom = g_new(MemoryRegion, 1);
+    MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
 
     /* Initialize SOC */
     object_initialize(&s->soc, sizeof(s->soc), TYPE_RISCV_HART_ARRAY);
@@ -246,10 +246,10 @@ static void riscv_sifive_u_init(MachineState *machine)
     create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
     /* boot rom */
-    memory_region_init_ram(boot_rom, NULL, "riscv.sifive.u.mrom",
+    memory_region_init_ram(mask_rom, NULL, "riscv.sifive.u.mrom",
                            memmap[SIFIVE_U_MROM].base, &error_fatal);
-    memory_region_set_readonly(boot_rom, true);
-    memory_region_add_subregion(sys_memory, 0x0, boot_rom);
+    memory_region_set_readonly(mask_rom, true);
+    memory_region_add_subregion(sys_memory, 0x0, mask_rom);
 
     if (machine->kernel_filename) {
         load_kernel(machine->kernel_filename);
@@ -279,6 +279,7 @@ static void riscv_sifive_u_init(MachineState *machine)
     qemu_fdt_dumpdtb(s->fdt, s->fdt_size);
     cpu_physical_memory_write(memmap[SIFIVE_U_MROM].base +
         sizeof(reset_vec), s->fdt, s->fdt_size);
+    memory_region_set_readonly(mask_rom, true);
 
     /* MMIO */
     s->plic = sifive_plic_create(memmap[SIFIVE_U_PLIC].base,
diff --git a/hw/riscv/spike.c b/hw/riscv/spike.c
index 7710333..74edf33 100644
--- a/hw/riscv/spike.c
+++ b/hw/riscv/spike.c
@@ -173,7 +173,7 @@ static void spike_v1_10_0_board_init(MachineState *machine)
     SpikeState *s = g_new0(SpikeState, 1);
     MemoryRegion *system_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
-    MemoryRegion *boot_rom = g_new(MemoryRegion, 1);
+    MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
 
     /* Initialize SOC */
     object_initialize(&s->soc, sizeof(s->soc), TYPE_RISCV_HART_ARRAY);
@@ -196,9 +196,9 @@ static void spike_v1_10_0_board_init(MachineState *machine)
     create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
     /* boot rom */
-    memory_region_init_ram(boot_rom, NULL, "riscv.spike.bootrom",
+    memory_region_init_ram(mask_rom, NULL, "riscv.spike.mrom",
                            s->fdt_size + 0x2000, &error_fatal);
-    memory_region_add_subregion(system_memory, 0x0, boot_rom);
+    memory_region_add_subregion(system_memory, 0x0, mask_rom);
 
     if (machine->kernel_filename) {
         load_kernel(machine->kernel_filename);
@@ -228,9 +228,10 @@ static void spike_v1_10_0_board_init(MachineState *machine)
     qemu_fdt_dumpdtb(s->fdt, s->fdt_size);
     cpu_physical_memory_write(memmap[SPIKE_MROM].base + sizeof(reset_vec),
         s->fdt, s->fdt_size);
+    memory_region_set_readonly(mask_rom, true);
 
     /* initialize HTIF using symbols found in load_kernel */
-    htif_mm_init(system_memory, boot_rom, &s->soc.harts[0].env, serial_hds[0]);
+    htif_mm_init(system_memory, mask_rom, &s->soc.harts[0].env, serial_hds[0]);
 
     /* Core Local Interruptor (timer and IPI) */
     sifive_clint_create(memmap[SPIKE_CLINT].base, memmap[SPIKE_CLINT].size,
@@ -244,7 +245,7 @@ static void spike_v1_09_1_board_init(MachineState *machine)
     SpikeState *s = g_new0(SpikeState, 1);
     MemoryRegion *system_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
-    MemoryRegion *boot_rom = g_new(MemoryRegion, 1);
+    MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
 
     /* Initialize SOC */
     object_initialize(&s->soc, sizeof(s->soc), TYPE_RISCV_HART_ARRAY);
@@ -264,9 +265,9 @@ static void spike_v1_09_1_board_init(MachineState *machine)
         main_mem);
 
     /* boot rom */
-    memory_region_init_ram(boot_rom, NULL, "riscv.spike.bootrom",
+    memory_region_init_ram(mask_rom, NULL, "riscv.spike.mrom",
                            0x40000, &error_fatal);
-    memory_region_add_subregion(system_memory, 0x0, boot_rom);
+    memory_region_add_subregion(system_memory, 0x0, mask_rom);
 
     if (machine->kernel_filename) {
         load_kernel(machine->kernel_filename);
@@ -325,9 +326,10 @@ static void spike_v1_09_1_board_init(MachineState *machine)
     /* copy in the config string */
     cpu_physical_memory_write(memmap[SPIKE_MROM].base + sizeof(reset_vec),
         config_string, config_string_len);
+    memory_region_set_readonly(mask_rom, true);
 
     /* initialize HTIF using symbols found in load_kernel */
-    htif_mm_init(system_memory, boot_rom, &s->soc.harts[0].env, serial_hds[0]);
+    htif_mm_init(system_memory, mask_rom, &s->soc.harts[0].env, serial_hds[0]);
 
     /* Core Local Interruptor (timer and IPI) */
     sifive_clint_create(memmap[SPIKE_CLINT].base, memmap[SPIKE_CLINT].size,
diff --git a/hw/riscv/virt.c b/hw/riscv/virt.c
index f8c19b4..f1e3641 100644
--- a/hw/riscv/virt.c
+++ b/hw/riscv/virt.c
@@ -270,7 +270,7 @@ static void riscv_virt_board_init(MachineState *machine)
     RISCVVirtState *s = g_new0(RISCVVirtState, 1);
     MemoryRegion *system_memory = get_system_memory();
     MemoryRegion *main_mem = g_new(MemoryRegion, 1);
-    MemoryRegion *boot_rom = g_new(MemoryRegion, 1);
+    MemoryRegion *mask_rom = g_new(MemoryRegion, 1);
     char *plic_hart_config;
     size_t plic_hart_config_len;
     int i;
@@ -296,9 +296,9 @@ static void riscv_virt_board_init(MachineState *machine)
     create_fdt(s, memmap, machine->ram_size, machine->kernel_cmdline);
 
     /* boot rom */
-    memory_region_init_ram(boot_rom, NULL, "riscv_virt_board.bootrom",
+    memory_region_init_ram(mask_rom, NULL, "riscv_virt_board.mrom",
                            s->fdt_size + 0x2000, &error_fatal);
-    memory_region_add_subregion(system_memory, 0x0, boot_rom);
+    memory_region_add_subregion(system_memory, 0x0, mask_rom);
 
     if (machine->kernel_filename) {
         uint64_t kernel_entry = load_kernel(machine->kernel_filename);
@@ -339,6 +339,7 @@ static void riscv_virt_board_init(MachineState *machine)
     qemu_fdt_dumpdtb(s->fdt, s->fdt_size);
     cpu_physical_memory_write(memmap[VIRT_MROM].base + sizeof(reset_vec),
         s->fdt, s->fdt_size);
+    memory_region_set_readonly(mask_rom, true);
 
     /* create PLIC hart topology configuration string */
     plic_hart_config_len = (strlen(VIRT_PLIC_HART_CONFIG) + 1) * smp_cpus;
diff --git a/include/hw/riscv/spike.h b/include/hw/riscv/spike.h
index d85a64e..179b6cf 100644
--- a/include/hw/riscv/spike.h
+++ b/include/hw/riscv/spike.h
@@ -22,20 +22,12 @@
 #define TYPE_RISCV_SPIKE_V1_09_1_BOARD "riscv.spike_v1_9_1"
 #define TYPE_RISCV_SPIKE_V1_10_0_BOARD "riscv.spike_v1_10"
 
-#define SPIKE(obj) \
-    OBJECT_CHECK(SpikeState, (obj), TYPE_RISCV_SPIKE_BOARD)
-
 typedef struct {
-    /*< private >*/
-    SysBusDevice parent_obj;
-
-    /*< public >*/
     RISCVHartArrayState soc;
     void *fdt;
     int fdt_size;
 } SpikeState;
 
-
 enum {
     SPIKE_MROM,
     SPIKE_CLINT,
