Messages in this thread Patch in this message | | | Date | Mon, 27 Feb 2023 09:36:25 -0800 | Subject | [PATCH v4 26/33] mm: prevent do_swap_page from handling page faults under VMA lock | From | Suren Baghdasaryan <> |
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Due to the possibility of do_swap_page dropping mmap_lock, abort fault handling under VMA lock and retry holding mmap_lock. This can be handled more gracefully in the future.
Signed-off-by: Suren Baghdasaryan <surenb@google.com> Reviewed-by: Laurent Dufour <laurent.dufour@fr.ibm.com> --- mm/memory.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/mm/memory.c b/mm/memory.c index 8855846a361b..af3c2c59cd11 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3689,6 +3689,11 @@ vm_fault_t do_swap_page(struct vm_fault *vmf) if (!pte_unmap_same(vmf)) goto out; + if (vmf->flags & FAULT_FLAG_VMA_LOCK) { + ret = VM_FAULT_RETRY; + goto out; + } + entry = pte_to_swp_entry(vmf->orig_pte); if (unlikely(non_swap_entry(entry))) { if (is_migration_entry(entry)) { -- 2.39.2.722.g9855ee24e9-goog
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