syzbot

==================================================================
BUG: KCSAN: data-race in __writeback_single_inode / inode_io_list_del

read-write to 0xffff88800997a6b8 of 8 bytes by task 8463 on cpu 0:
 inode_io_list_del_locked fs/fs-writeback.c:148 [inline]
 inode_io_list_del+0x91/0x240 fs/fs-writeback.c:1127
 evict+0xac/0x470 fs/inode.c:565
 iput_final fs/inode.c:1654 [inline]
 iput+0x421/0x510 fs/inode.c:1680
 dentry_unlink_inode+0x1f3/0x210 fs/dcache.c:374
 d_delete+0x70/0xa0 fs/dcache.c:2470
 vfs_rmdir+0x271/0x290 fs/namei.c:3727
 do_rmdir+0x16e/0x300 fs/namei.c:3774
 __do_sys_rmdir fs/namei.c:3792 [inline]
 __se_sys_rmdir fs/namei.c:3790 [inline]
 __x64_sys_rmdir+0x2c/0x30 fs/namei.c:3790
 do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88800997a6b8 of 8 bytes by task 304 on cpu 1:
 __writeback_single_inode+0x45/0x560 fs/fs-writeback.c:1457
 writeback_sb_inodes+0x6a0/0x1020 fs/fs-writeback.c:1721
 wb_writeback+0x27d/0x660 fs/fs-writeback.c:1894
 wb_do_writeback+0x101/0x5d0 fs/fs-writeback.c:2039
 wb_workfn+0xb8/0x410 fs/fs-writeback.c:2080
 process_one_work+0x3e1/0x950 kernel/workqueue.c:2272
 worker_thread+0x635/0xb90 kernel/workqueue.c:2418
 kthread+0x1fa/0x220 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 304 Comm: kworker/u4:3 Not tainted 5.10.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: writeback wb_workfn (flush-8:0)
==================================================================