Re: [PATCH] x86: make sure wakeup code is below 1M -v2

[Yinghai Lu <yinghai@kernel.org>]

ykzhao wrote:
> On Thu, 2009-11-12 at 11:12 +0800, Yinghai Lu wrote:
>> ykzhao wrote:
>>> On Thu, 2009-11-12 at 03:05 +0800, Yinghai Lu wrote:
>>>> ykzhao wrote:
>>>>> On Wed, 2009-11-11 at 10:27 +0800, Yinghai Lu wrote:
>>>>>> try to find_e820_area/reserve_early, and call acpi_reserve_memory early
>>>>>>
>>>>>> to get area is below 1M
>>>>>>
>>>>>> -v2: change function name to acpi_reserve_wakeup_memory according to Rafael
>>>>> It seems that the function of find_e820_area is called in several
>>>>> places.
>>>>>    >Initmem_init: bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT,
>>>>> bootmap_size, PAGE_SIZE);
>>>>>    
>>>>> If we also call it in the acpi_reserve_wakeup_memory, do we get the same
>>>>> base address as that obtained in initmem_init?
>>>> no. find_e820_area will check the reserve res array that could be updated by reserve_early.
>>> It will check the reserved region array when calling the function of
>>> find_e820_area. 
>>> But it seems that the array is not updated when the find_e820_area is
>>> called in the function of initmem_init.
>> right after that will use reserve_bootmem for those range in initmem_init.
> Yes. The reserve_bootmem is called for the range in initmem_init.
> But the reserved_early array is not updated.

it is not needed anymore because bootmem for that node is ready at that point, could use 
reserve_bootmem_node directly. and before that early_res_to_bootmem will convert that early resource that 
fall into that node range to bootmem reserved too.

please check code setup_node_bootmem/early_node_mem/early_res_to_bootmem ...and reserve_bootmem_node...

YH