Re: [hatari-devel] Truncated PC address value with code running in TT-RAM?

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On Samstag, 30. März 2019 18:33:03 CET Nicolas Pomarède wrote:

>yes it could be possible that linux install its own mmu table to handle 
>page swapping

Yes, definitely. Not only for page swapping, but every process gets the same 
virtual address space, regardless where it is located physically in RAM. This 
is different from current Mint behaviour for example, where the MMU is only 
used for protection, but there is a 1-to-1 mapping for addresses.

> then it seems the bug is not in Hatari or in
> the cpu core.

Maybe not in the CPU core, but apparently in the disassembler, using the 
functions that use physical addresses to fetch opcodes. When the MMU  is 
active, you need to translate them first (it is not just adding the memory 
bank offset, you really have to go through the MMU table).

I'm not sure how Hatari handles this currently, but in Aranym there are 
functions like phys_get_long(), mmu_get_long() etc. for this purpose.

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