syzbot

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

write to 0xffff888101a27c10 of 8 bytes by task 10410 on cpu 1:
 page_cache_delete_batch mm/filemap.c:340 [inline]
 delete_from_page_cache_batch+0x597/0x820 mm/filemap.c:358
 truncate_inode_pages_range+0x482/0x10e0 mm/truncate.c:366
 truncate_inode_pages+0x20/0x30 mm/truncate.c:476
 kill_bdev fs/block_dev.c:86 [inline]
 __blkdev_put+0x24f/0x460 fs/block_dev.c:1572
 blkdev_put+0x222/0x2a0 fs/block_dev.c:1632
 kill_block_super+0x7b/0x90 fs/super.c:1396
 reiserfs_kill_sb+0xe8/0xf0 fs/reiserfs/super.c:570
 deactivate_locked_super+0x6a/0xb0 fs/super.c:335
 mount_bdev+0x204/0x290 fs/super.c:1368
 get_super_block+0x2d/0x40 fs/reiserfs/super.c:2606
 legacy_get_tree+0x70/0xc0 fs/fs_context.c:592
 vfs_get_tree+0x4a/0x1a0 fs/super.c:1496
 do_new_mount fs/namespace.c:2881 [inline]
 path_mount+0x11b6/0x1ca0 fs/namespace.c:3211
 do_mount fs/namespace.c:3224 [inline]
 __do_sys_mount fs/namespace.c:3432 [inline]
 __se_sys_mount+0x23d/0x2e0 fs/namespace.c:3409
 __x64_sys_mount+0x63/0x70 fs/namespace.c:3409
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff888101a27c10 of 8 bytes by task 5 on cpu 0:
 nr_blockdev_pages+0x7c/0xd0 fs/block_dev.c:942
 si_meminfo+0x3a/0x60 mm/page_alloc.c:5404
 update_defense_level+0x34/0x550 net/netfilter/ipvs/ip_vs_ctl.c:101
 defense_work_handler+0x1b/0x80 net/netfilter/ipvs/ip_vs_ctl.c:235
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2275
 worker_thread+0x616/0xa70 kernel/workqueue.c:2421
 kthread+0x20b/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.11.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_long defense_work_handler
==================================================================