============================================ WARNING: possible recursive locking detected 5.16.0-rc4-syzkaller #0 Not tainted -------------------------------------------- iou-wrk-19621/19631 is trying to acquire lock: ffff8880143fb818 (&wqe->lock){+.+.}-{2:2}, at: io_worker_cancel_cb+0xf1/0x210 fs/io-wq.c:187 but task is already holding lock: ffff8880143fb818 (&wqe->lock){+.+.}-{2:2}, at: io_wq_worker_sleeping+0xc2/0x120 fs/io-wq.c:700 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&wqe->lock); lock(&wqe->lock); *** DEADLOCK *** May be due to missing lock nesting notation 1 lock held by iou-wrk-19621/19631: #0: ffff8880143fb818 (&wqe->lock){+.+.}-{2:2}, at: io_wq_worker_sleeping+0xc2/0x120 fs/io-wq.c:700 stack backtrace: CPU: 1 PID: 19631 Comm: iou-wrk-19621 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain kernel/locking/lockdep.c:3788 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5027 lock_acquire kernel/locking/lockdep.c:5637 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 io_worker_cancel_cb+0xf1/0x210 fs/io-wq.c:187 io_wq_cancel_tw_create fs/io-wq.c:1220 [inline] io_queue_worker_create+0x5a7/0x630 fs/io-wq.c:372 io_wqe_dec_running+0x1ce/0x210 fs/io-wq.c:398 io_wq_worker_sleeping+0xca/0x120 fs/io-wq.c:701 sched_submit_work kernel/sched/core.c:6295 [inline] schedule+0x1d0/0x260 kernel/sched/core.c:6323 schedule_timeout+0x1db/0x2a0 kernel/time/timer.c:1857 unix_wait_for_peer+0x23c/0x270 net/unix/af_unix.c:1314 unix_dgram_sendmsg+0x16bd/0x1950 net/unix/af_unix.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 io_send+0x392/0x4d0 fs/io_uring.c:4883 io_issue_sqe+0x3814/0x7060 fs/io_uring.c:6694 io_wq_submit_work+0x1db/0x580 fs/io_uring.c:6836 io_worker_handle_work+0x9bc/0x1900 fs/io-wq.c:574 io_wqe_worker+0x55e/0xcb0 fs/io-wq.c:630 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295