Commit dade922f authored by Jordan Justen's avatar Jordan Justen Committed by Anthony Liguori
Browse files

isapc: Fix non-KVM qemu boot (read/write memory for isapc BIOS) 



The isapc machine with seabios currently requires the BIOS region
to be read/write memory rather than read-only memory.

KVM currently cannot support the BIOS as a ROM region, but qemu
in non-KVM mode can. Based on this, isapc machine currently only
works with KVM.

To work-around this isapc issue, this change avoids marking the
BIOS as readonly for isapc.

This change also will allow KVM to start supporting ROM mode
via KVM_CAP_READONLY_MEM.

Signed-off-by: default avatarJordan Justen <jordan.l.justen@intel.com>
Reviewed-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1369816047-16384-2-git-send-email-jordan.l.justen@intel.com
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 338ea905

hw/block/pc_sysfw.c

+11 −5
Original line number Diff line number Diff line
@@ -39,6 +39,7 @@ 
typedef struct PcSysFwDevice {

    SysBusDevice busdev;

    uint8_t rom_only;

    uint8_t isapc_ram_fw;

} PcSysFwDevice;



static void pc_isa_bios_init(MemoryRegion *rom_memory,
@@ -139,7 +140,7 @@ static void pc_system_flash_init(MemoryRegion *rom_memory, 
    pc_isa_bios_init(rom_memory, flash_mem, size);

}



static void old_pc_system_rom_init(MemoryRegion *rom_memory)

static void old_pc_system_rom_init(MemoryRegion *rom_memory, bool isapc_ram_fw)

{

    char *filename;

    MemoryRegion *bios, *isa_bios;
@@ -163,7 +164,9 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory) 
    bios = g_malloc(sizeof(*bios));

    memory_region_init_ram(bios, "pc.bios", bios_size);

    vmstate_register_ram_global(bios);

    if (!isapc_ram_fw) {

        memory_region_set_readonly(bios, true);

    }

    ret = rom_add_file_fixed(bios_name, (uint32_t)(-bios_size), -1);

    if (ret != 0) {

    bios_error:
@@ -186,7 +189,9 @@ static void old_pc_system_rom_init(MemoryRegion *rom_memory) 
                                        0x100000 - isa_bios_size,

                                        isa_bios,

                                        1);

    if (!isapc_ram_fw) {

        memory_region_set_readonly(isa_bios, true);

    }



    /* map all the bios at the top of memory */

    memory_region_add_subregion(rom_memory,
@@ -216,7 +221,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory) 
    qdev_init_nofail(DEVICE(sysfw_dev));



    if (sysfw_dev->rom_only) {

        old_pc_system_rom_init(rom_memory);

        old_pc_system_rom_init(rom_memory, sysfw_dev->isapc_ram_fw);

        return;

    }
@@ -234,7 +239,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory) 
            exit(1);

        } else {

            sysfw_dev->rom_only = 1;

            old_pc_system_rom_init(rom_memory);

            old_pc_system_rom_init(rom_memory, sysfw_dev->isapc_ram_fw);

            return;

        }

    }
@@ -255,6 +260,7 @@ void pc_system_firmware_init(MemoryRegion *rom_memory) 
}



static Property pcsysfw_properties[] = {

    DEFINE_PROP_UINT8("isapc_ram_fw", PcSysFwDevice, isapc_ram_fw, 0),

    DEFINE_PROP_UINT8("rom_only", PcSysFwDevice, rom_only, 0),

    DEFINE_PROP_END_OF_LIST(),

};

hw/i386/pc_piix.c

+5 −0
Original line number Diff line number Diff line
@@ -713,6 +713,11 @@ static QEMUMachine isapc_machine = { 
            .property = "rom_only",

            .value    = stringify(1),

        },

        {

            .driver   = "pc-sysfw",

            .property = "isapc_ram_fw",

            .value    = stringify(1),

        },

        { /* end of list */ }

    },

    DEFAULT_MACHINE_OPTIONS,