Re: [PATCH] badram filtering

[phcoder <phcoder@gmail.com>]

Hello. I'm now writing the code to make multiboot and bsd work on EFI 
based on my grub_machine_memory_iterate for EFI. MY code will be the 
same for all i386 branches. It's quite complete except that I had no 
time yet to test it. I'l submit once it works
I was thinking and found another utility for badram: BIOS hooks. They 
are actually allocating take some memory and then removing it from mmap. 
If bios mmap hook and kernels get their mmap from the same source we can 
ensure that bios hooks won't be overwritten by the kernel independently 
how it acquired memory map. So I think badram patch should be extended 
to allow arbitrary additions to mmap.
P.S. sorry if this e-mail isn't clear enough I've just had a long day of 
studies
phcoder wrote:
>> 2) when badram variable is set corresponding memory chunks should be 
>> removed from memory manager
>> 3) add a method to specify badram in init.c so that grub2 itself has 
>> no risk of using any of this memory. I propose to embed initial 
>> environment in core.img. Then prefix and root can be changed to use 
>> this mechanism. It would also be able to override this initial 
>> environment through multiboot command line when grub2 is loaded by 
>> multiboot loader
>>
>>
>> Robert Millan wrote:
>>> Hi,
>>>
>>> This patch implements badram filtering in GRUB.  It's the same idea 
>>> as in
>>> http://rick.vanrein.org/linux/badram/ but applied to GRUB.
>>>
>>> The badram module sits between loaders (or other users like lsmmap) and
>>> filters the mmap entries, but only when user previously set the "badram"
>>> variable (whose syntax is the same as the one in badram patch for 
>>> Linux).
>>>
>>> NOTE this won't affect loadees that get the memory map from BIOS instead
>>> of from GRUB.  This means it currently works for Multiboot and for the
>>> new/experimental Linux loader.
>>>
>>>
>>>
>>> ------------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> Grub-devel mailing list
>>> Grub-devel@gnu.org
>>> http://lists.gnu.org/mailman/listinfo/grub-devel
>>
>>
> 
> 


-- 

Regards
Vladimir 'phcoder' Serbinenko