On Tue, Apr 09, 2024 at 04:10:22PM +0200, Oscar Salvador wrote: > On Sun, Apr 07, 2024 at 04:54:56PM +0800, Miaohe Lin wrote: > > In short, below scene breaks the lock dependency chain: > > > > memory_failure > > __page_handle_poison > > zone_pcp_disable -- lock(pcp_batch_high_lock) > > dissolve_free_huge_page > > __hugetlb_vmemmap_restore_folio > > static_key_slow_dec > > cpus_read_lock -- rlock(cpu_hotplug_lock) > > > > Fix this by calling drain_all_pages() instead. > > > > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > > Acked-by: Oscar Salvador <osalvador@xxxxxxx> On a second though, disabling pcp via zone_pcp_disable() was a deterministic approach. Now, with drain_all_pages() we drain PCP queues to buddy, but nothing guarantees that those pages do not end up in a PCP queue again before we the call to take_page_off_budy() if we need refilling, right? I guess we can live with that because we will let the system know that we failed to isolate that page. -- Oscar Salvador SUSE Labs
