On Wed, 17 Aug 2022 15:06:39 +1000, Russell Currey wrote:

Add support for execute-only memory (XOM) for the Radix MMU by using an
execute-only mapping, as opposed to the RX mapping used by powerpc's
other MMUs.

The Hash MMU already supports XOM through the execute-only pkey,
which is a separate mechanism shared with x86.  A PROT_EXEC-only mapping
will map to RX, and then the pkey will be applied on top of it.

[...]

Applied to powerpc/next.

[1/2] powerpc/mm: Support execute-only memory on the Radix MMU
      https://git.kernel.org/powerpc/c/395cac7752b905318ae454a8b859d4c190485510
[2/2] selftests/powerpc: Add a test for execute-only memory
      https://git.kernel.org/powerpc/c/98acee3f8db451eaab9fbd422e523c228aacf08c

cheers