Christoph Hellwig [off-list ref] writes:

On Fri, May 31, 2024 at 12:28:21AM +1000, Michael Ellerman wrote:

quoted

No that's wrong. The actual hardware page size is 4K, but
CONFIG_PAGE_SIZE and PAGE_SHIFT etc. is 64K.

So at least for this user the driver used to work with 64K pages, and
now doesn't.

Which suggested that the communicated max_hw_sectors is wrong, and
previously we were saved by the block layer increasing it to
PAGE_SIZE after a warning.  Should we just increment it to 64k?

It looks like that user actually only has the CDROM hanging off
pata_macio, so it's possible it has been broken previously and they
didn't notice. I'll see if they can confirm the CDROM has been working
up until now.

I can test the CDROM on my G5 next week.

cheers