diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/events/uprobes.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index b4ca8898fe17..eac24f39c2c2 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -173,6 +173,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, DEFINE_FOLIO_VMA_WALK(pvmw, old_folio, vma, addr, 0); int err; struct mmu_notifier_range range; + pte_t pte; mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, mm, addr, addr + PAGE_SIZE); @@ -192,6 +193,16 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, if (!page_vma_mapped_walk(&pvmw)) goto unlock; VM_BUG_ON_PAGE(addr != pvmw.address, old_page); + pte = ptep_get(pvmw.pte); + + /* + * Handle PFN swap PTES, such as device-exclusive ones, that actually + * map pages: simply trigger GUP again to fix it up. + */ + if (unlikely(!pte_present(pte))) { + page_vma_mapped_walk_done(&pvmw); + goto unlock; + } if (new_page) { folio_get(new_folio); @@ -206,7 +217,7 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr, inc_mm_counter(mm, MM_ANONPAGES); } - flush_cache_page(vma, addr, pte_pfn(ptep_get(pvmw.pte))); + flush_cache_page(vma, addr, pte_pfn(pte)); ptep_clear_flush(vma, addr, pvmw.pte); if (new_page) set_pte_at(mm, addr, pvmw.pte, |