On (04/25/16 15:18), Yu Zhao wrote: > On Mon, Apr 25, 2016 at 05:20:10PM -0400, Dan Streetman wrote: > > Add a work_struct to struct zpool, and change zpool_destroy_pool to > > defer calling the pool implementation destroy. > > > > The zsmalloc pool destroy function, which is one of the zpool > > implementations, may sleep during destruction of the pool. However > > zswap, which uses zpool, may call zpool_destroy_pool from atomic > > context. So we need to defer the call to the zpool implementation > > to destroy the pool. > > > > This is essentially the same as Yu Zhao's proposed patch to zsmalloc, > > but moved to zpool. > > Thanks, Dan. Sergey also mentioned another call path that triggers the > same problem (BUG: scheduling while atomic): > rcu_process_callbacks() > __zswap_pool_release() > zswap_pool_destroy() > zswap_cpu_comp_destroy() > cpu_notifier_register_begin() > mutex_lock(&cpu_add_remove_lock); > So I was thinking zswap_pool_destroy() might be done in workqueue in zswap.c. > This way we fix both call paths. right, I'm not sure the patch addressed all of the issues. -ss -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>