[PATCH v4] ksm: fix conflict between mmput and scan_get_next_rmap_item

A concurrency issue about KSM in the function scan_get_next_rmap_item. task A (ksmd): |task B (the mm's task): | mm = slot->mm; | down_read(>mmap_sem); |

[PATCH v4] ksm: fix conflict between mmput and scan_get_next_rmap_item

A concurrency issue about KSM in the function scan_get_next_rmap_item. task A (ksmd): |task B (the mm's task): | mm = slot->mm; | down_read(>mmap_sem); |