diff --git a/mm/memory.c b/mm/memory.c index 93fdb73bf0ca..50dc21038c09 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3427,6 +3427,10 @@ static vm_fault_t __do_fault(struct vm_fault *vmf) struct vm_area_struct *vma = vmf->vma; vm_fault_t ret; + /* Do not check unstable pmd, if it's changed will retry later */ + if (vmf->flags & FAULT_FLAG_SPECULATIVE) + goto skip_pmd_checks; + /* * Preallocate pte before we take page_lock because this might lead to * deadlocks for memcg reclaim which waits for pages under writeback: @@ -3449,6 +3453,7 @@ static vm_fault_t __do_fault(struct vm_fault *vmf) smp_wmb(); /* See comment in __pte_alloc() */ } +skip_pmd_checks: ret = vma->vm_ops->fault(vmf); if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE | VM_FAULT_RETRY | VM_FAULT_DONE_COW))) @@ -3822,7 +3827,8 @@ static vm_fault_t do_fault_around(struct vm_fault *vmf) end_pgoff = min3(end_pgoff, vma_pages(vmf->vma) + vmf->vma->vm_pgoff - 1, start_pgoff + nr_pages - 1); - if (pmd_none(*vmf->pmd)) { + if (!(vmf->flags & FAULT_FLAG_SPECULATIVE) && + pmd_none(*vmf->pmd)) { vmf->prealloc_pte = pte_alloc_one(vmf->vma->vm_mm); if (!vmf->prealloc_pte) goto out; @@ -4189,16 +4195,11 @@ static vm_fault_t handle_pte_fault(struct vm_fault *vmf) pte_t entry; vm_fault_t ret = 0; + /* Do not check unstable pmd, if it's changed will retry later */ + if (vmf->flags & FAULT_FLAG_SPECULATIVE) + goto skip_pmd_checks; + if (unlikely(pmd_none(*vmf->pmd))) { - /* - * In the case of the speculative page fault handler we abort - * the speculative path immediately as the pmd is probably - * in the way to be converted in a huge one. We will try - * again holding the mmap_sem (which implies that the collapse - * operation is done). - */ - if (vmf->flags & FAULT_FLAG_SPECULATIVE) - return VM_FAULT_RETRY; /* * Leave __pte_alloc() until later: because vm_ops->fault may * want to allocate huge page, and if we expose page table @@ -4206,8 +4207,7 @@ static vm_fault_t handle_pte_fault(struct vm_fault *vmf) * concurrent faults and from rmap lookups. */ vmf->pte = NULL; - } else if (!(vmf->flags & FAULT_FLAG_SPECULATIVE)) { - /* See comment in pte_alloc_one_map() */ + } else { if (pmd_devmap_trans_unstable(vmf->pmd)) return 0; /* @@ -4237,6 +4237,7 @@ static vm_fault_t handle_pte_fault(struct vm_fault *vmf) } } +skip_pmd_checks: if (!vmf->pte) { if (vma_is_anonymous(vmf->vma)) return do_anonymous_page(vmf);