syzbot

==================================================================
BUG: KCSAN: data-race in d_lru_del / fsnotify_parent

write to 0xffff88811f168000 of 4 bytes by task 8602 on cpu 1:
 d_lru_del+0x57/0xf0 fs/dcache.c:410
 select_collect+0x171/0x190 fs/dcache.c:1486
 d_walk+0x1b9/0x540 fs/dcache.c:1307
 shrink_dcache_parent+0xa9/0x2a0 fs/dcache.c:1546
 d_invalidate fs/dcache.c:1658 [inline]
 d_invalidate+0x87/0x170 fs/dcache.c:1643
 proc_invalidate_siblings_dcache+0x303/0x330 fs/proc/inode.c:149
 proc_flush_pid+0x20/0x30 fs/proc/base.c:3276
 release_task+0x94f/0xce0 kernel/exit.c:221
 wait_task_zombie kernel/exit.c:1078 [inline]
 wait_consider_task+0x1b43/0x1c60 kernel/exit.c:1305
 do_wait_thread kernel/exit.c:1368 [inline]
 do_wait+0x1c7/0x4c0 kernel/exit.c:1439
 kernel_wait4+0x146/0x230 kernel/exit.c:1611
 __do_sys_wait4+0xea/0x100 kernel/exit.c:1623
 __se_sys_wait4 kernel/exit.c:1619 [inline]
 __x64_sys_wait4+0x59/0x70 kernel/exit.c:1619
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88811f168000 of 4 bytes by task 5272 on cpu 0:
 fsnotify_parent+0x4d/0x1b0 fs/notify/fsnotify.c:153
 fsnotify_file include/linux/fsnotify.h:74 [inline]
 fsnotify_close include/linux/fsnotify.h:281 [inline]
 __fput+0x121/0x500 fs/file_table.c:266
 ____fput+0x1b/0x30 fs/file_table.c:313
 task_work_run+0xba/0x120 kernel/task_work.c:123
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2ae/0x2c0 arch/x86/entry/common.c:165
 prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
 do_syscall_64+0x38b/0x3b0 arch/x86/entry/common.c:305
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5272 Comm: systemd-journal Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================