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Subject: Re: [PATCH v6 4/9] mm: thp: Introduce anon_orders and
 anon_always_mask sysfs files
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On Sun, 08 Oct 2023 09:54:22 +1100 Michael Ellerman <mpe@ellerman.id.au> wrote:

> > I don't know why powerpc's PTE_INDEX_SIZE is variable.
> 
> To allow a single vmlinux to boot using either the Hashed Page Table
> MMU, or Radix Tree MMU, which have different page table geometry.
> 
> That's a pretty crucial feature for distros, so that they can build a
> single kernel to boot on Power8/9/10.

Dumb question: why can't distros ship two kernels and have the boot
loader (or something else) pick the appropriate one?