syzbot

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BUG: KCSAN: data-race in __delete_from_page_cache / nr_blockdev_pages

write to 0xffff88812a346668 of 8 bytes by task 26367 on cpu 1:
 page_cache_delete mm/filemap.c:153 [inline]
 __delete_from_page_cache+0x1e4/0x490 mm/filemap.c:238
 __remove_mapping+0x2ea/0x540 mm/vmscan.c:925
 shrink_page_list+0x1086/0x2970 mm/vmscan.c:1425
 shrink_inactive_list+0x390/0x8d0 mm/vmscan.c:1945
 shrink_list mm/vmscan.c:2164 [inline]
 shrink_lruvec+0x4c9/0xd20 mm/vmscan.c:2482
 shrink_node_memcgs mm/vmscan.c:2671 [inline]
 shrink_node+0x30a/0x1000 mm/vmscan.c:2777
 shrink_zones mm/vmscan.c:2980 [inline]
 do_try_to_free_pages+0x230/0xb30 mm/vmscan.c:3033
 try_to_free_mem_cgroup_pages+0x1f7/0x4b0 mm/vmscan.c:3355
 reclaim_high.constprop.0+0xee/0x140 mm/memcontrol.c:2232
 mem_cgroup_handle_over_high+0x8f/0x180 mm/memcontrol.c:2313
 tracehook_notify_resume include/linux/tracehook.h:197 [inline]
 exit_to_usermode_loop+0x20a/0x2c0 arch/x86/entry/common.c:164
 prepare_exit_to_usermode+0x190/0x1c0 arch/x86/entry/common.c:195
 swapgs_restore_regs_and_return_to_usermode+0x0/0x40

read to 0xffff88812a346668 of 8 bytes by task 11864 on cpu 0:
 nr_blockdev_pages+0x6c/0xc0 fs/block_dev.c:952
 si_meminfo+0x3a/0x60 mm/page_alloc.c:5126
 update_defense_level+0x4a/0xa80 net/netfilter/ipvs/ip_vs_ctl.c:101
 defense_work_handler+0x3a/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:224
 process_one_work+0x424/0x930 kernel/workqueue.c:2264
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2410
 kthread+0x1cb/0x1f0 kernel/kthread.c:255
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11864 Comm: kworker/0:17 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events defense_work_handler
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