On Tue, Feb 15, 2022 at 07:29:42AM +0100, Christoph Hellwig wrote:
On Tue, Feb 15, 2022 at 12:37:41AM +0000, Al Viro wrote:
Perhaps simply wrap that sucker into #ifdef CONFIG_CPU_HAS_ADDRESS_SPACES
(and trim the comment down to "coldfire and 68000 will pick generic
variant")?
I wonder if we should invert CONFIG_ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE,
select the separate address space config for s390, sparc64, non-coldfire
m68k and mips with EVA and then just have one single access_ok for
overlapping address space (as added by Arnd) and non-overlapping ones
(always return true).
parisc is also such... How about
select ALTERNATE_SPACE_USERLAND
for that bunch? While we are at it, how many unusual access_ok() instances are
left after this series? arm64, itanic, um, anything else?
FWIW, sparc32 has a slightly unusual instance (see uaccess_32.h there); it's
obviously cheaper than generic and I wonder if the trick is legitimate (and
applicable elsewhere, perhaps)...
