Re: [Qemu-devel] [PATCH v2] Allow additions of ACPI tables from command line

[Anthony Liguori <anthony@codemonkey.ws>]

Gleb Natapov wrote:
> On Mon, Feb 16, 2009 at 09:27:26AM -0600, Anthony Liguori wrote:
>   
>> Gleb Natapov wrote:
>>     
>>> This is needed to dynamically add SLIC tables with Windows
>>> activation keys.
>>>
>>> Signed-off-by: Gleb Natapov <gleb@redhat.com>
>>> diff --git a/hw/acpi.c b/hw/acpi.c
>>> index 4338d02..7175598 100644
>>> --- a/hw/acpi.c
>>> +++ b/hw/acpi.c
>>> @@ -561,3 +561,170 @@ void qemu_system_powerdown(void)
>>>      }
>>>  }
>>>  #endif
>>> +
>>> +struct acpi_table_header
>>> +{
>>> +    char signature [4];    /* ACPI signature (4 ASCII characters) */
>>> +    uint32_t length;          /* Length of table, in bytes, including header */
>>> +    uint8_t revision;         /* ACPI Specification minor version # */
>>> +    uint8_t checksum;         /* To make sum of entire table == 0 */
>>> +    char oem_id [6];       /* OEM identification */
>>> +    char oem_table_id [8]; /* OEM table identification */
>>> +    uint32_t oem_revision;    /* OEM revision number */
>>> +    char asl_compiler_id [4]; /* ASL compiler vendor ID */
>>> +    uint32_t asl_compiler_revision; /* ASL compiler revision number */
>>> +};
>>>   
>>>       
>> I don't have a lot of confidence that this table is going to be padded  
>> correctly by all compilers on all architectures.  I'd suggest explicit  
>> padding.
>>
>>     
> __attribute_((packed)) should be enough, no?
>   

Yup.

>>> +    if (get_param_value(buf, sizeof(buf), "oem_id", t)) {
>>> +        strncpy(acpi_hdr.oem_id, buf, 6);
>>>   
>>>       
>> is oem_id supposed to be NULL terminated or just NULL padded?
>>     
>
> ACPI spec rev 3.0b 18.2.1:
> OEM ID of up to 6 characters. If the OEM ID is shorter than 6
> characters, it can be terminated with a NULL character.
>   

Ok, I figured as much but wanted to double check.

Regards,

Anthony Liguori

> --
> 			Gleb.
>
>
>