| Message ID | 1517227200-20412-4-git-send-email-will.deacon@arm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index b44992ec9643..fc7902bda02b 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -118,6 +118,10 @@ static bool pgattr_change_is_safe(u64 old, u64 new) if ((old | new) & PTE_CONT) return false; + /* Transitioning from Global to Non-Global is safe */ + if (((old ^ new) == PTE_NG) && (new & PTE_NG)) + return true; + return ((old ^ new) & ~mask) == 0; }
Break-before-make is not needed when transitioning from Global to Non-Global mappings, provided that the contiguous hint is not being used. Signed-off-by: Will Deacon <will.deacon@arm.com> --- arch/arm64/mm/mmu.c | 4 ++++ 1 file changed, 4 insertions(+)