mm: use clear_user_(high)page() for arch with special user folio handling

Some architectures have special handling after clearing user folios:
architectures, which set cpu_dcache_is_aliasing() to true, require
flushing dcache; arc, which sets cpu_icache_is_aliasing() to true, changes
folio->flags to make icache coherent to dcache.  So __GFP_ZERO using only
clear_page() is not enough to zero user folios and clear_user_(high)page()
must be used.  Otherwise, user data will be corrupted.

Fix it by always clearing user folios with clear_user_(high)page() when
cpu_dcache_is_aliasing() is true or cpu_icache_is_aliasing() is true. 
Rename alloc_zeroed() to user_alloc_needs_zeroing() and invert the logic
to clarify its intend.

Link: https://lkml.kernel.org/r/[email protected]
Fixes: 5708d96da20b ("mm: avoid zeroing user movable page twice with init_on_alloc=1")
Signed-off-by: Zi Yan <[email protected]>
Reported-by: Geert Uytterhoeven <[email protected]>
Closes: https://lore.kernel.org/linux-mm/CAMuHMdV1hRp_NtR5YnJo=HsfgKQeH91J537Gh4gKk3PFZhSkbA@mail.gmail.com/
Tested-by: Geert Uytterhoeven <[email protected]>
Acked-by: Vlastimil Babka <[email protected]>
Cc: Alexander Potapenko <[email protected]>
Cc: David Hildenbrand <[email protected]>
Cc: John Hubbard <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Kefeng Wang <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Matthew Wilcox <[email protected]>
Cc: Miaohe Lin <[email protected]>
Cc: Ryan Roberts <[email protected]>
Cc: Vineet Gupta <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions