On Tue, 2019-06-25 at 14:17:27 UTC, Andrea Arcangeli wrote:

25078dc1f74be16b858e914f52cc8f4d03c2271a first introduced an off by
one error in the ZONE_DMA initialization of PPC_BOOK3E_64=y and since
9739ab7eda459f0669ec9807e0d9be5020bab88c the off by one applies to
PPC32=y too. This simply corrects the off by one and should resolve
crashes like below:

[   65.179101] page 0x7fff outside node 0 zone DMA [ 0x0 - 0x7fff ]

Unfortunately in various MM places "max" means a non inclusive end of
range. free_area_init_nodes max_zone_pfn parameter is one case and
MAX_ORDER is another one (unrelated) that comes by memory.

Reported-by: Zorro Lang <redacted>
Fixes: 25078dc1f74b ("powerpc: use mm zones more sensibly")
Fixes: 9739ab7eda45 ("powerpc: enable a 30-bit ZONE_DMA for 32-bit pmac")
Signed-off-by: Andrea Arcangeli <redacted>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Applied to powerpc fixes, thanks.

https://git.kernel.org/powerpc/c/03800e0526ee25ed7c843ca1e57b69ac2a5af642

cheers