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bh=AEG8OzwZLGvoqaVY7tGYihpu0BfBvqq0Eim1ylAxXK4=; b=6uaIx7yhC9EZ8xWbLIvCiCeB9NH2KUH/+m5q/FYXa4XUMME3Pi+CijoMHike01lwb6KxUJ JxCAtnQ1dCBYNhJiut45vI1QaaiZjoV2KjXf+HyI533shKQ2dQvRIUeWy7wbWFQINwEW6+ E6NK2ROg7kfREz55SZXXu+dB28eli1k= X-Rspam-User: X-Rspamd-Queue-Id: 106A01C000D X-Rspamd-Server: rspam08 X-Stat-Signature: kj1b9e6rwy5rauzn44jwjrkgdxkopydr Authentication-Results: imf20.hostedemail.com; dkim=pass header.d=linux-foundation.org header.s=korg header.b="RcXjl9m/"; dmarc=none; spf=pass (imf20.hostedemail.com: domain of akpm@linux-foundation.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=akpm@linux-foundation.org X-HE-Tag: 1664132107-667508 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 23 Sep 2022 17:14:38 -0700 (PDT) Hugh Dickins wrote: > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -2060,7 +2060,7 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) > struct vm_area_struct *vma = vmf->vma; > struct inode *inode = file_inode(vma->vm_file); > gfp_t gfp = mapping_gfp_mask(inode->i_mapping); > - struct folio *folio; > + struct folio *folio = NULL; > int err; > vm_fault_t ret = VM_FAULT_LOCKED; > > @@ -2127,7 +2127,8 @@ static vm_fault_t shmem_fault(struct vm_fault *vmf) > gfp, vma, vmf, &ret); > if (err) > return vmf_error(err); > - vmf->page = folio_file_page(folio, vmf->pgoff); > + if (folio) > + vmf->page = folio_file_page(folio, vmf->pgoff); > return ret; > } I grabbed this as a fix against shmem-convert-shmem_fault-to-use-shmem_get_folio_gfp.patch. Hopefully someone can send along something more formal when ready.