mm: handle write faults to RO pages under the VMA lock

I think this is a pretty rare occurrence, but for consistency handle
faults with the VMA lock held the same way that we handle other faults
with the VMA lock held.

Link: https://lkml.kernel.org/r/20231006195318.4087158-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Matthew Wilcox (Oracle) 2023-10-06 20:53:18 +01:00 committed by Andrew Morton
parent 12214eba19
commit 4a68fef16d
1 changed files with 6 additions and 7 deletions

View File

@ -3301,10 +3301,9 @@ static vm_fault_t wp_pfn_shared(struct vm_fault *vmf)
vm_fault_t ret;
pte_unmap_unlock(vmf->pte, vmf->ptl);
if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
vma_end_read(vmf->vma);
return VM_FAULT_RETRY;
}
ret = vmf_can_call_fault(vmf);
if (ret)
return ret;
vmf->flags |= FAULT_FLAG_MKWRITE;
ret = vma->vm_ops->pfn_mkwrite(vmf);
@ -3328,10 +3327,10 @@ static vm_fault_t wp_page_shared(struct vm_fault *vmf, struct folio *folio)
vm_fault_t tmp;
pte_unmap_unlock(vmf->pte, vmf->ptl);
if (vmf->flags & FAULT_FLAG_VMA_LOCK) {
tmp = vmf_can_call_fault(vmf);
if (tmp) {
folio_put(folio);
vma_end_read(vmf->vma);
return VM_FAULT_RETRY;
return tmp;
}
tmp = do_page_mkwrite(vmf, folio);