Revert "i915: fix remap_io_sg to verify the pgprot"

This reverts commit b12d691ea5e01db42ccf3b4207e57cb3ce7cfe91.

It turns out this is not ready for primetime yet.  The intentions are
good, but using remap_pfn_range() requires that there is nothing already
mapped in the area, and the i915 code seems to very much intentionally
remap the same area multiple times.

That will then just trigger the

                BUG_ON(!pte_none(*pte));

in mm/memory.c: remap_pte_range().

There are also reports of mapping type inconsistencies, resulting in
warnings and in screen corruption.

Link: https://lore.kernel.org/lkml/20210519024322.GA29704@xsang-OptiPlex-9020/
Link: https://lore.kernel.org/lkml/YKUjvoaKKggAmpIR@sf/
Link: https://lore.kernel.org/lkml/[email protected]/
Reported-by: kernel test robot <[email protected]>
Reported-by: Kalle Valo <[email protected]>
Reported-by: Hans de Goede <[email protected]>
Reported-by: Sergei Trofimovich <[email protected]>
Acked-by: Christoph Hellwig <[email protected]>
Cc: Chris Wilson <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Jani Nikula <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Rodrigo Vivi <[email protected]>
Cc: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions