diff options
| -rw-r--r-- | include/asm-generic/tlb.h | 33 |
1 files changed, 17 insertions, 16 deletions
diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h index 897ca66338d5..cb2167c89eee 100644 --- a/include/asm-generic/tlb.h +++ b/include/asm-generic/tlb.h @@ -303,6 +303,7 @@ struct mmu_gather { */ unsigned int vma_exec : 1; unsigned int vma_huge : 1; + unsigned int vma_pfn : 1; unsigned int batch_count; @@ -373,7 +374,6 @@ tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) { } #else /* CONFIG_MMU_GATHER_NO_RANGE */ #ifndef tlb_flush - /* * When an architecture does not provide its own tlb_flush() implementation * but does have a reasonably efficient flush_vma_range() implementation @@ -393,6 +393,9 @@ static inline void tlb_flush(struct mmu_gather *tlb) flush_tlb_range(&vma, tlb->start, tlb->end); } } +#endif + +#endif /* CONFIG_MMU_GATHER_NO_RANGE */ static inline void tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) @@ -410,17 +413,9 @@ tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) */ tlb->vma_huge = is_vm_hugetlb_page(vma); tlb->vma_exec = !!(vma->vm_flags & VM_EXEC); + tlb->vma_pfn = !!(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP)); } -#else - -static inline void -tlb_update_vma_flags(struct mmu_gather *tlb, struct vm_area_struct *vma) { } - -#endif - -#endif /* CONFIG_MMU_GATHER_NO_RANGE */ - static inline void tlb_flush_mmu_tlbonly(struct mmu_gather *tlb) { /* @@ -507,16 +502,22 @@ static inline void tlb_start_vma(struct mmu_gather *tlb, struct vm_area_struct * static inline void tlb_end_vma(struct mmu_gather *tlb, struct vm_area_struct *vma) { - if (tlb->fullmm || IS_ENABLED(CONFIG_MMU_GATHER_MERGE_VMAS)) + if (tlb->fullmm) return; /* - * Do a TLB flush and reset the range at VMA boundaries; this avoids - * the ranges growing with the unused space between consecutive VMAs, - * but also the mmu_gather::vma_* flags from tlb_start_vma() rely on - * this. + * VM_PFNMAP is more fragile because the core mm will not track the + * page mapcount -- there might not be page-frames for these PFNs after + * all. Force flush TLBs for such ranges to avoid munmap() vs + * unmap_mapping_range() races. */ - tlb_flush_mmu_tlbonly(tlb); + if (tlb->vma_pfn || !IS_ENABLED(CONFIG_MMU_GATHER_MERGE_VMAS)) { + /* + * Do a TLB flush and reset the range at VMA boundaries; this avoids + * the ranges growing with the unused space between consecutive VMAs. + */ + tlb_flush_mmu_tlbonly(tlb); + } } /* |