syzbot

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BUG: KCSAN: data-race in list_lru_count_one / list_lru_del

write to 0xffff88812ad05198 of 8 bytes by task 8909 on cpu 1:
 list_lru_del+0x1dc/0x2a0 mm/list_lru.c:149
 workingset_update_node+0x9e/0x120 mm/workingset.c:424
 xas_update lib/xarray.c:350 [inline]
 update_node lib/xarray.c:751 [inline]
 xas_store+0x218/0xd10 lib/xarray.c:838
 __add_to_page_cache_locked+0x33b/0x800 mm/filemap.c:859
 add_to_page_cache_lru+0xc7/0x260 mm/filemap.c:921
 ext4_mpage_readpages+0x31c/0x14d0 fs/ext4/readpage.c:259
 ext4_readpages+0x8e/0xb0 fs/ext4/inode.c:3243
 read_pages+0xa2/0x360 mm/readahead.c:126
 __do_page_cache_readahead+0x358/0x380 mm/readahead.c:212
 ra_submit mm/internal.h:62 [inline]
 do_sync_mmap_readahead mm/filemap.c:2407 [inline]
 filemap_fault+0x1027/0x1410 mm/filemap.c:2493
 ext4_filemap_fault+0x5b/0x74 fs/ext4/inode.c:6033
 __do_fault+0xa8/0x1e0 mm/memory.c:3450
 do_read_fault mm/memory.c:3846 [inline]
 do_fault mm/memory.c:3975 [inline]
 handle_pte_fault mm/memory.c:4215 [inline]
 __handle_mm_fault+0x295c/0x2da0 mm/memory.c:4345
 handle_mm_fault+0x21c/0x540 mm/memory.c:4382
 do_user_addr_fault arch/x86/mm/fault.c:1464 [inline]
 do_page_fault+0x48a/0xa96 arch/x86/mm/fault.c:1535
 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1203

read to 0xffff88812ad05198 of 8 bytes by task 2678 on cpu 0:
 list_lru_count_one+0xb4/0x120 mm/list_lru.c:183
 list_lru_shrink_count include/linux/list_lru.h:123 [inline]
 count_shadow_nodes+0x4f/0x490 mm/workingset.c:437
 do_shrink_slab+0xb3/0x5b0 mm/vmscan.c:430
 shrink_slab mm/vmscan.c:673 [inline]
 shrink_slab+0x153/0x540 mm/vmscan.c:646
 shrink_node_memcgs mm/vmscan.c:2673 [inline]
 shrink_node+0x357/0x1000 mm/vmscan.c:2777
 kswapd_shrink_node mm/vmscan.c:3523 [inline]
 balance_pgdat+0x658/0xd20 mm/vmscan.c:3681
 kswapd+0x3f3/0x8c0 mm/vmscan.c:3935
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2678 Comm: kswapd0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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