Re: [PATCH 05/14] x86, ACPI: Find acpi tables in initrd early at head_32.S/head64.c

[Yinghai Lu]

On Thu, Mar 7, 2013 at 9:57 PM, Tejun Heo <tj@xxxxxxxxxx> wrote:
> On Thu, Mar 07, 2013 at 08:58:31PM -0800, Yinghai Lu wrote:
>> diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
>> index 73afd11..ca08f0e 100644
>> --- a/arch/x86/kernel/head_32.S
>> +++ b/arch/x86/kernel/head_32.S
>> @@ -149,6 +149,10 @@ ENTRY(startup_32)
>>       call load_ucode_bsp
>>  #endif
>>
>> +#ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
>> +     call x86_acpi_override_find
>> +#endif
>
> The function is always defined.  We can probalby lose ifdef here?

just mimic microcode updating again.

>
> Also, does it really have to be called from head_32.S?  No way this
> can be done after entering C code?  It would be great if you can
> explain overall design choices in the head message (and important
> patches).

have to be with head_32.S and it is with 32bit flat mode, so could access
4G blow without setting page table.

Will try add to more in the change log.

>
>> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
>> index 668e658..d43545a 100644
>> --- a/arch/x86/kernel/setup.c
>> +++ b/arch/x86/kernel/setup.c
>> @@ -424,6 +424,32 @@ static void __init reserve_initrd(void)
>>  }
>>  #endif /* CONFIG_BLK_DEV_INITRD */
>>
>> +#ifdef CONFIG_ACPI_INITRD_TABLE_OVERRIDE
>> +void __init x86_acpi_override_find(void)
>> +{
>> +     unsigned long ramdisk_image, ramdisk_size;
>> +     unsigned char *p = NULL;
>> +
>> +#ifdef CONFIG_X86_32
>> +     struct boot_params *boot_params_p;
>> +
>> +     boot_params_p = (struct boot_params *)__pa_symbol(&boot_params);
>> +     ramdisk_image = boot_params_p->hdr.ramdisk_image;
>> +     ramdisk_size  = boot_params_p->hdr.ramdisk_size;
>> +     p = (unsigned char *)ramdisk_image;
>> +     acpi_initrd_override_find(p, ramdisk_size, true);
>> +#else
>> +     ramdisk_image = get_ramdisk_image();
>> +     ramdisk_size  = get_ramdisk_size();
>> +     if (ramdisk_image)
>> +             p = __va(ramdisk_image);
>> +     acpi_initrd_override_find(p, ramdisk_size, false);
>> +#endif
>> +}
>> +#else
>> +void __init x86_acpi_override_find(void) { }
>
> And add a comment here why we're not doing static inline for the dummy
> function?

...
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/