Re: [PATCH] mips: fix start of free memory when using initrd

[Greg Ungerer <gerg@snapgear.com>]

David Daney wrote:
> On 09/09/2010 11:10 PM, Greg Ungerer wrote:
>>
>> Hi David,
>>
>> David Daney wrote:
> [...]
>>> We have the attached patch (plus a few more hacks), I don't think it
>>> is universally safe to change the calculation of reserved_end.
>>> Although the patch has some code formatting problems you might
>>> consider using it as a starting point.>
>> I don't use the Cavium u-boot boot loader on this. (And don't use any
>> of the named blocks, or other data struct passing from the boot loader
>> to the kernel). So the patch is not really useful for me.
>>
>> But I am interested, why do you think it is not safe to change
>> reserved_end?
> 
> For Octeon it is probably safe, but there is a reason that this complex 
> logic for restricting the usable memory ranges exists.  Other targets 
> require it, so great care must be taken not to break the non-octeon 
> targets.
> 
>>
>> There is the possible overlap of the kernels bootmem setup data
>> that is not checked (which sparc does for example). But otherwise
>> what problems do you see here?
>>
> 
> I lack the imagination necessary to come up with a failing scenario, but 
> I am also paranoid, so I see danger everywhere.

Good answer :-)

Regards
Greg


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Greg Ungerer  --  Principal Engineer        EMAIL:     gerg@snapgear.com
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