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... Restart the iteration if the inode is already off shmem_swaplist list to fix the issue. Fixes: b56a2d8af9147 ("mm: rid swapoff of quadratic complexity") Signed-off-by: Kemeng Shi --- mm/shmem.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/mm/shmem.c b/mm/shmem.c index 495e661eb8bb..0fed94c2bc09 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -1505,6 +1505,7 @@ int shmem_unuse(unsigned int type) return 0; mutex_lock(&shmem_swaplist_mutex); +start_over: list_for_each_entry_safe(info, next, &shmem_swaplist, swaplist) { if (!info->swapped) { list_del_init(&info->swaplist); @@ -1530,6 +1531,8 @@ int shmem_unuse(unsigned int type) wake_up_var(&info->stop_eviction); if (error) break; + if (list_empty(&info->swaplist)) + goto start_over; } mutex_unlock(&shmem_swaplist_mutex); -- 2.30.0