From: "Matthew Wilcox (Oracle)" willy@infradead.org
from mainline-v6.7-rc1 commit 4a68fef16df9d88d528094116f8bbd2dbfa62089 category: other bugzilla: https://gitee.com/openeuler/kernel/issues/I8K7C7
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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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 Signed-off-by: Tong Tiangen tongtiangen@huawei.com --- mm/memory.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c index f1399e9f527d..e1a0eb8b776a 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3304,10 +3304,9 @@ 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); @@ -3331,10 +3330,10 @@ 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);