==================================================================
BUG: KCSAN: data-race in __delete_from_page_cache / nr_blockdev_pages

write to 0xffff88812a3239a8 of 8 bytes by task 3856 on cpu 1:
 page_cache_delete mm/filemap.c:153 [inline]
 __delete_from_page_cache+0x1d8/0x490 mm/filemap.c:238
 __remove_mapping+0x2db/0x530 mm/vmscan.c:939
 remove_mapping+0x3d/0xb0 mm/vmscan.c:961
 invalidate_complete_page mm/truncate.c:215 [inline]
 invalidate_inode_page+0x1c9/0x200 mm/truncate.c:264
 invalidate_mapping_pages+0x377/0x900 mm/truncate.c:607
 invalidate_bdev+0x7f/0x90 fs/block_dev.c:98
 __loop_clr_fd+0x250/0x740 drivers/block/loop.c:1140
 loop_clr_fd drivers/block/loop.c:1237 [inline]
 lo_ioctl+0x24c/0xc80 drivers/block/loop.c:1606
 __blkdev_driver_ioctl block/ioctl.c:277 [inline]
 blkdev_ioctl+0xbe5/0x1260 block/ioctl.c:582
 block_ioctl+0x95/0xc0 fs/block_dev.c:1983
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x84f/0xcf0 fs/ioctl.c:732
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88812a3239a8 of 8 bytes by task 12 on cpu 0:
 nr_blockdev_pages+0x73/0xc0 fs/block_dev.c:952
 si_meminfo+0x3e/0x60 mm/page_alloc.c:5151
 update_defense_level+0x40/0xb50 net/netfilter/ipvs/ip_vs_ctl.c:101
 defense_work_handler+0x3d/0xd0 net/netfilter/ipvs/ip_vs_ctl.c:224
 process_one_work+0x40b/0x8d0 kernel/workqueue.c:2264
 worker_thread+0xa0/0x800 kernel/workqueue.c:2410
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events defense_work_handler
==================================================================