On Tue, 25 Aug 2020 17:55:35 +1000, Nicholas Piggin wrote:

The ISA v3.1 the copy-paste facility has a new memory move functionality
which allows the copy buffer to be pasted to domestic memory (RAM) as
opposed to foreign memory (accelerator).

This means the POWER9 trick of avoiding the cp_abort on context switch if
the process had not mapped foreign memory does not work on POWER10. Do the
cp_abort unconditionally there.

[...]

Applied to powerpc/next.

[1/1] powerpc/64s: handle ISA v3.1 local copy-paste context switches
      https://git.kernel.org/powerpc/c/dc462267d2d7aacffc3c1d99b02d7a7c59db7c66

cheers