On Tue, 2020-03-31 at 01:23:38 UTC, Alexey Kardashevskiy wrote:
> Unlike normal memory ("memory" compatible type in the FDT),
> the persistent memory ("ibm,pmemory" in the FDT) can be mapped anywhere
> in the guest physical space and it can be used for DMA.
>
> In order to maintain 1:1 mapping via the huge DMA window, we need to
> know the maximum physical address at the time of the window setup.
> So far we've been looking at "memory" nodes but "ibm,pmemory" does not
> have fixed addresses and the persistent memory may be mapped afterwards.
>
> Since the persistent memory is still backed with page structs,
> use MAX_PHYSMEM_BITS as the upper limit.
>
> This effectively disables huge DMA window in LPAR under pHyp if
> persistent memory is present but this is the best we can do.
>
> Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
Applied to powerpc next, thanks.
https://git.kernel.org/powerpc/c/54fc3c681ded9437e4548e2501dc1136b23cfa9a
cheers
