syzbot

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BUG: KCSAN: data-race in list_lru_count_one / list_lru_del

read to 0xffff88812b054298 of 8 bytes by task 1768 on cpu 1:
 list_lru_count_one+0xbd/0x130 mm/list_lru.c:193
 list_lru_shrink_count include/linux/list_lru.h:123 [inline]
 count_shadow_nodes+0x51/0x4a0 mm/workingset.c:437
 do_shrink_slab+0xb7/0x5a0 mm/vmscan.c:444
 shrink_slab mm/vmscan.c:687 [inline]
 shrink_slab+0x147/0x540 mm/vmscan.c:660
 shrink_node_memcgs mm/vmscan.c:2687 [inline]
 shrink_node+0x34a/0xfe0 mm/vmscan.c:2791
 kswapd_shrink_node mm/vmscan.c:3539 [inline]
 balance_pgdat+0x68d/0xda0 mm/vmscan.c:3697
 kswapd+0x35b/0x800 mm/vmscan.c:3948
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

write to 0xffff88812b054298 of 8 bytes by task 5517 on cpu 0:
 list_lru_del+0x181/0x3f0 mm/list_lru.c:159
 workingset_update_node+0xa9/0x130 mm/workingset.c:424
 xas_update lib/xarray.c:349 [inline]
 update_node lib/xarray.c:750 [inline]
 xas_store+0x20f/0xd00 lib/xarray.c:837
 __add_to_page_cache_locked+0x342/0x780 mm/filemap.c:881
 add_to_page_cache_lru+0xc4/0x260 mm/filemap.c:943
 ext4_mpage_readpages+0x329/0x1580 fs/ext4/readpage.c:247
 ext4_readpages+0x92/0xc0 fs/ext4/inode.c:3244
 read_pages+0xa2/0x2d0 mm/readahead.c:126
 __do_page_cache_readahead+0x353/0x390 mm/readahead.c:212
 ra_submit mm/internal.h:62 [inline]
 do_sync_mmap_readahead mm/filemap.c:2422 [inline]
 filemap_fault+0xe8b/0x10a0 mm/filemap.c:2508
 ext4_filemap_fault+0x59/0x72 fs/ext4/inode.c:5977
 __do_fault+0xae/0x1f0 mm/memory.c:3188
 do_read_fault mm/memory.c:3585 [inline]
 do_fault mm/memory.c:3714 [inline]
 handle_pte_fault mm/memory.c:3945 [inline]
 __handle_mm_fault+0x270d/0x2e00 mm/memory.c:4075
 handle_mm_fault+0x21b/0x530 mm/memory.c:4112
 do_user_addr_fault arch/x86/mm/fault.c:1441 [inline]
 __do_page_fault+0x456/0x8d0 arch/x86/mm/fault.c:1506
 do_page_fault+0x38/0x194 arch/x86/mm/fault.c:1530
 page_fault+0x34/0x40 arch/x86/entry/entry_64.S:1203

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5517 Comm: udevd Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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