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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 | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/mm/shmem.c b/mm/shmem.c index 495e661eb8bb..aeeddf612baa 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); @@ -1523,13 +1524,15 @@ int shmem_unuse(unsigned int type) cond_resched(); mutex_lock(&shmem_swaplist_mutex); - next = list_next_entry(info, swaplist); - if (!info->swapped) - list_del_init(&info->swaplist); if (atomic_dec_and_test(&info->stop_eviction)) wake_up_var(&info->stop_eviction); if (error) break; + if (list_empty(&info->swaplist)) + goto start_over; + next = list_next_entry(info, swaplist); + if (!info->swapped) + list_del_init(&info->swaplist); } mutex_unlock(&shmem_swaplist_mutex); -- 2.30.0