From 6a1bdb173f9967b2329aab0f25bcba963f54e06b Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Wed, 30 Sep 2020 13:20:40 +0100 Subject: arm64: mm: Make flush_tlb_fix_spurious_fault() a no-op Our use of broadcast TLB maintenance means that spurious page-faults that have been handled already by another CPU do not require additional TLB maintenance. Make flush_tlb_fix_spurious_fault() a no-op and rely on the existing TLB invalidation instead. Add an explicit flush_tlb_page() when making a page dirty, as the TLB is permitted to cache the old read-only entry. Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20200728092220.GA21800@willie-the-truck Signed-off-by: Will Deacon --- arch/arm64/mm/fault.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'arch/arm64/mm/fault.c') diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index f07333e86c2f..a696a7921da4 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -218,7 +218,9 @@ int ptep_set_access_flags(struct vm_area_struct *vma, pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); } while (pteval != old_pteval); - flush_tlb_fix_spurious_fault(vma, address); + /* Invalidate a stale read-only entry */ + if (dirty) + flush_tlb_page(vma, address); return 1; } -- cgit v1.2.3