============================================ WARNING: possible recursive locking detected 5.16.0-rc2-syzkaller #0 Not tainted -------------------------------------------- syz-executor.1/26429 is trying to acquire lock: ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_flush_timeouts+0x80/0x34c fs/io_uring.c:1587 but task is already holding lock: ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x49/0x319 fs/io_uring.c:5702 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&ctx->timeout_lock); lock(&ctx->timeout_lock); *** DEADLOCK *** May be due to missing lock nesting notation 2 locks held by syz-executor.1/26429: #0: ffff88801f7183d8 (&ctx->completion_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] #0: ffff88801f7183d8 (&ctx->completion_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x38/0x319 fs/io_uring.c:5701 #1: ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] #1: ffff88801f718418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x49/0x319 fs/io_uring.c:5702 stack backtrace: CPU: 0 PID: 26429 Comm: syz-executor.1 Not tainted 5.16.0-rc2-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+0x1dc/0x2d8 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline] check_deadlock kernel/locking/lockdep.c:2999 [inline] validate_chain+0x5984/0x8240 kernel/locking/lockdep.c:3788 __lock_acquire+0x1382/0x2b00 kernel/locking/lockdep.c:5027 lock_acquire+0x19f/0x4d0 kernel/locking/lockdep.c:5637 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xcf/0x110 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:374 [inline] io_flush_timeouts+0x80/0x34c fs/io_uring.c:1587 __io_commit_cqring_flush+0x80/0xbf fs/io_uring.c:1618 io_commit_cqring fs/io_uring.c:1626 [inline] io_poll_remove_one+0x4bd/0x610 fs/io_uring.c:5684 io_poll_remove_all+0x24c/0x319 fs/io_uring.c:5709 io_uring_try_cancel_requests+0x320/0x42a fs/io_uring.c:9668 io_uring_cancel_generic+0x44f/0x661 fs/io_uring.c:9833 io_uring_files_cancel include/linux/io_uring.h:16 [inline] do_exit+0x281/0x24f0 kernel/exit.c:787 do_group_exit+0x168/0x2d0 kernel/exit.c:929 get_signal+0x1740/0x2120 kernel/signal.c:2852 arch_do_signal_or_restart+0x9c/0x730 arch/x86/kernel/signal.c:868 handle_signal_work kernel/entry/common.c:148 [inline] exit_to_user_mode_loop kernel/entry/common.c:172 [inline] exit_to_user_mode_prepare+0x191/0x220 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0b96a1fae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f0b93f95218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000000 RBX: 00007f0b96b32f68 RCX: 00007f0b96a1fae9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f0b96b32f68 RBP: 00007f0b96b32f60 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0b96b32f6c R13: 00007ffd3231aacf R14: 00007f0b93f95300 R15: 0000000000022000