syzbot

==================================================================
BUG: KCSAN: data-race in __blkdev_put / __blkdev_put

write to 0xffff8881013650a0 of 4 bytes by task 13035 on cpu 1:
 __blkdev_put+0x122/0x460 fs/block_dev.c:1573
 blkdev_put+0x23e/0x2c0 fs/block_dev.c:1636
 blkdev_close+0x47/0x50 fs/block_dev.c:1644
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881013650a0 of 4 bytes by task 13031 on cpu 0:
 __blkdev_put+0x5a/0x460 fs/block_dev.c:1566
 __blkdev_put+0x3b9/0x460 fs/block_dev.c:1586
 blkdev_put+0x23e/0x2c0 fs/block_dev.c:1636
 blkdev_close+0x47/0x50 fs/block_dev.c:1644
 __fput+0x25b/0x4e0 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0xae/0x130 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x156/0x190 kernel/entry/common.c:209
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:302
 do_syscall_64+0x49/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000005 -> 0x00000003

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13031 Comm: systemd-udevd Not tainted 5.13.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================