[PATCH v14-fix 06/11] mm: multi-gen LRU: delete overcautious VM_WARN_ON_ONCE()

[Yu Zhao <yuzhao@google.com>]

As commented, it is "unlikely but not a bug when reset_batch_size() is
pending". This one was never reported but another similar one in
lru_gen_use_mm(), which is already deleted, indeed happened.

kernel BUG at mm/vmscan.c:4592!
Call Trace:
 ? get_nr_to_scan+0x89/0x2a0
 lru_gen_shrink_lruvec+0x1aa/0x2b0
 shrink_node_memcg+0x68/0x450
 shrink_node+0x25c/0x620
 shrink_zones+0xf4/0x170
 do_try_to_free_pages+0xa5/0x280
 try_to_free_mem_cgroup_pages+0x161/0x1f0
 try_charge+0x2b1/0x940
 __mem_cgroup_try_charge+0x102/0x3d0
 do_anonymous_page+0x152/0x440
 handle_mm_fault+0x9d2/0x1030
 __do_page_fault+0x388/0x550
 do_page_fault+0x2b/0x60
 page_fault+0x45/0x50

Reported-by: David Rientjes <rientjes@google.com>
Signed-off-by: Yu Zhao <yuzhao@google.com>
---
 mm/vmscan.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/mm/vmscan.c b/mm/vmscan.c
index e509e896c019..77d2d08950ba 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -5171,9 +5171,6 @@ static bool __maybe_unused state_is_valid(struct lruvec *lruvec)
 		for_each_gen_type_zone(gen, type, zone) {
 			if (!list_empty(&lrugen->lists[gen][type][zone]))
 				return false;
-
-			/* unlikely but not a bug when reset_batch_size() is pending */
-			VM_WARN_ON_ONCE(lrugen->nr_pages[gen][type][zone]);
 		}
 	}
 
-- 
2.37.3.968.ga6b4b080e4-goog