Re: [PATCH 07/14] hw/i386/vmport: Add support for CMD_GETBIOSUUID

["Michael S. Tsirkin" <mst@redhat.com>]

On Tue, Mar 10, 2020 at 01:54:04AM +0200, Liran Alon wrote:
> This is VMware documented functionallity that some guests rely on.
> Returns the BIOS UUID of the current virtual machine.
> 
> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
> Signed-off-by: Liran Alon <liran.alon@oracle.com>

So this at least seems guest-visible.

So I suspect you need to add properties to
disable this for old machine types, to avoid
breaking compatibility with live-migration.


> ---
>  hw/i386/vmport.c     | 14 ++++++++++++++
>  include/hw/i386/pc.h |  1 +
>  2 files changed, 15 insertions(+)
> 
> diff --git a/hw/i386/vmport.c b/hw/i386/vmport.c
> index 2ae5afc42b50..7687f3368a55 100644
> --- a/hw/i386/vmport.c
> +++ b/hw/i386/vmport.c
> @@ -26,6 +26,7 @@
>  #include "hw/i386/pc.h"
>  #include "hw/input/i8042.h"
>  #include "hw/qdev-properties.h"
> +#include "sysemu/sysemu.h"
>  #include "sysemu/hw_accel.h"
>  #include "qemu/log.h"
>  #include "trace.h"
> @@ -121,6 +122,18 @@ static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
>      return port_state->vmx_version;
>  }
>  
> +static uint32_t vmport_cmd_get_bios_uuid(void *opaque, uint32_t addr)
> +{
> +    X86CPU *cpu = X86_CPU(current_cpu);
> +    uint32_t *uuid_parts = (uint32_t*)(qemu_uuid.data);
> +
> +    cpu->env.regs[R_EAX] = uuid_parts[0];
> +    cpu->env.regs[R_EBX] = uuid_parts[1];
> +    cpu->env.regs[R_ECX] = uuid_parts[2];
> +    cpu->env.regs[R_EDX] = uuid_parts[3];
> +    return cpu->env.regs[R_EAX];
> +}
> +
>  static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
>  {
>      X86CPU *cpu = X86_CPU(current_cpu);
> @@ -171,6 +184,7 @@ static void vmport_realizefn(DeviceState *dev, Error **errp)
>      port_state = s;
>      /* Register some generic port commands */
>      vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
> +    vmport_register(VMPORT_CMD_GETBIOSUUID, vmport_cmd_get_bios_uuid, NULL);
>      vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
>  }
>  
> diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
> index 7f15a01137b1..ea87eb93511e 100644
> --- a/include/hw/i386/pc.h
> +++ b/include/hw/i386/pc.h
> @@ -140,6 +140,7 @@ typedef uint32_t (VMPortReadFunc)(void *opaque, uint32_t address);
>  
>  typedef enum {
>      VMPORT_CMD_GETVERSION       = 10,
> +    VMPORT_CMD_GETBIOSUUID      = 19,
>      VMPORT_CMD_GETRAMSIZE       = 20,
>      VMPORT_CMD_VMMOUSE_DATA     = 39,
>      VMPORT_CMD_VMMOUSE_STATUS   = 40,
> -- 
> 2.20.1