[...]

If we do something like mte_enable_kernel_asymm(), that one doesn't
return any error, just fall back to the default mode.

But, in case of mte_enable_kernel_asymm() need return to
change kasan_flag_write_only = false when it doesn't support which
used in KASAN Kunit test.

If we don't return anything, when user set the write_only but HW doesn't
support it, KUNIT test get failure since kasan_write_only_enabled()
return true thou HW doesn't support it.

[...]

Thanks.
--
Sincerely,
Yeoreum Yun