diff options
| -rw-r--r-- | arch/arm64/include/asm/pgtable.h | 14 | ||||
| -rw-r--r-- | arch/arm64/include/asm/tlbflush.h | 56 | ||||
| -rw-r--r-- | arch/arm64/mm/contpte.c | 3 | ||||
| -rw-r--r-- | arch/arm64/mm/fault.c | 8 |
4 files changed, 72 insertions, 9 deletions
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index aa89c2e67ebc..25b3c31edb6c 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -130,12 +130,16 @@ static inline void arch_leave_lazy_mmu_mode(void) #endif /* CONFIG_TRANSPARENT_HUGEPAGE */ /* - * Outside of a few very special situations (e.g. hibernation), we always - * use broadcast TLB invalidation instructions, therefore a spurious page - * fault on one CPU which has been handled concurrently by another CPU - * does not need to perform additional invalidation. + * We use local TLB invalidation instruction when reusing page in + * write protection fault handler to avoid TLBI broadcast in the hot + * path. This will cause spurious page faults if stale read-only TLB + * entries exist. */ -#define flush_tlb_fix_spurious_fault(vma, address, ptep) do { } while (0) +#define flush_tlb_fix_spurious_fault(vma, address, ptep) \ + local_flush_tlb_page_nonotify(vma, address) + +#define flush_tlb_fix_spurious_fault_pmd(vma, address, pmdp) \ + local_flush_tlb_page_nonotify(vma, address) /* * ZERO_PAGE is a global shared page that is always zero: used diff --git a/arch/arm64/include/asm/tlbflush.h b/arch/arm64/include/asm/tlbflush.h index 18a5dc0c9a54..682a01df71d2 100644 --- a/arch/arm64/include/asm/tlbflush.h +++ b/arch/arm64/include/asm/tlbflush.h @@ -249,6 +249,19 @@ static inline unsigned long get_trans_granule(void) * cannot be easily determined, the value TLBI_TTL_UNKNOWN will * perform a non-hinted invalidation. * + * local_flush_tlb_page(vma, addr) + * Local variant of flush_tlb_page(). Stale TLB entries may + * remain in remote CPUs. + * + * local_flush_tlb_page_nonotify(vma, addr) + * Same as local_flush_tlb_page() except MMU notifier will not be + * called. + * + * local_flush_tlb_contpte(vma, addr) + * Invalidate the virtual-address range + * '[addr, addr+CONT_PTE_SIZE)' mapped with contpte on local CPU + * for the user address space corresponding to 'vma->mm'. Stale + * TLB entries may remain in remote CPUs. * * Finally, take a look at asm/tlb.h to see how tlb_flush() is implemented * on top of these routines, since that is our interface to the mmu_gather @@ -282,6 +295,33 @@ static inline void flush_tlb_mm(struct mm_struct *mm) mmu_notifier_arch_invalidate_secondary_tlbs(mm, 0, -1UL); } +static inline void __local_flush_tlb_page_nonotify_nosync(struct mm_struct *mm, + unsigned long uaddr) +{ + unsigned long addr; + + dsb(nshst); + addr = __TLBI_VADDR(uaddr, ASID(mm)); + __tlbi(vale1, addr); + __tlbi_user(vale1, addr); +} + +static inline void local_flush_tlb_page_nonotify(struct vm_area_struct *vma, + unsigned long uaddr) +{ + __local_flush_tlb_page_nonotify_nosync(vma->vm_mm, uaddr); + dsb(nsh); +} + +static inline void local_flush_tlb_page(struct vm_area_struct *vma, + unsigned long uaddr) +{ + __local_flush_tlb_page_nonotify_nosync(vma->vm_mm, uaddr); + mmu_notifier_arch_invalidate_secondary_tlbs(vma->vm_mm, uaddr & PAGE_MASK, + (uaddr & PAGE_MASK) + PAGE_SIZE); + dsb(nsh); +} + static inline void __flush_tlb_page_nosync(struct mm_struct *mm, unsigned long uaddr) { @@ -472,6 +512,22 @@ static inline void __flush_tlb_range(struct vm_area_struct *vma, dsb(ish); } +static inline void local_flush_tlb_contpte(struct vm_area_struct *vma, + unsigned long addr) +{ + unsigned long asid; + + addr = round_down(addr, CONT_PTE_SIZE); + + dsb(nshst); + asid = ASID(vma->vm_mm); + __flush_tlb_range_op(vale1, addr, CONT_PTES, PAGE_SIZE, asid, + 3, true, lpa2_is_enabled()); + mmu_notifier_arch_invalidate_secondary_tlbs(vma->vm_mm, addr, + addr + CONT_PTE_SIZE); + dsb(nsh); +} + static inline void flush_tlb_range(struct vm_area_struct *vma, unsigned long start, unsigned long end) { diff --git a/arch/arm64/mm/contpte.c b/arch/arm64/mm/contpte.c index c0557945939c..589bcf878938 100644 --- a/arch/arm64/mm/contpte.c +++ b/arch/arm64/mm/contpte.c @@ -622,8 +622,7 @@ int contpte_ptep_set_access_flags(struct vm_area_struct *vma, __ptep_set_access_flags(vma, addr, ptep, entry, 0); if (dirty) - __flush_tlb_range(vma, start_addr, addr, - PAGE_SIZE, true, 3); + local_flush_tlb_contpte(vma, start_addr); } else { __contpte_try_unfold(vma->vm_mm, addr, ptep, orig_pte); __ptep_set_access_flags(vma, addr, ptep, entry, dirty); diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c index d816ff44faff..4ecdfa6bcdbb 100644 --- a/arch/arm64/mm/fault.c +++ b/arch/arm64/mm/fault.c @@ -233,9 +233,13 @@ int __ptep_set_access_flags(struct vm_area_struct *vma, pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); } while (pteval != old_pteval); - /* Invalidate a stale read-only entry */ + /* + * Invalidate the local stale read-only entry. Remote stale entries + * may still cause page faults and be invalidated via + * flush_tlb_fix_spurious_fault(). + */ if (dirty) - flush_tlb_page(vma, address); + local_flush_tlb_page(vma, address); return 1; } |
