============================================ WARNING: possible recursive locking detected 5.16.0-rc2-syzkaller #0 Not tainted -------------------------------------------- syz-executor.2/18964 is trying to acquire lock: ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_flush_timeouts fs/io_uring.c:1587 [inline] ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: __io_commit_cqring_flush+0x108/0x50d fs/io_uring.c:1618 but task is already holding lock: ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x50/0x235 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.2/18964: #0: ffff88801e01d3d8 (&ctx->completion_lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:349 [inline] #0: ffff88801e01d3d8 (&ctx->completion_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x48/0x235 fs/io_uring.c:5701 #1: ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: spin_lock_irq include/linux/spinlock.h:374 [inline] #1: ffff88801e01d418 (&ctx->timeout_lock){+.+.}-{2:2}, at: io_poll_remove_all+0x50/0x235 fs/io_uring.c:5702 stack backtrace: CPU: 0 PID: 18964 Comm: syz-executor.2 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+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_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:374 [inline] io_flush_timeouts fs/io_uring.c:1587 [inline] __io_commit_cqring_flush+0x108/0x50d fs/io_uring.c:1618 io_commit_cqring fs/io_uring.c:1626 [inline] io_poll_remove_one fs/io_uring.c:5684 [inline] io_poll_remove_one.cold+0xd/0x12 fs/io_uring.c:5674 io_poll_remove_all+0x1af/0x235 fs/io_uring.c:5709 io_ring_ctx_wait_and_kill+0x1cc/0x322 fs/io_uring.c:9534 io_uring_release+0x42/0x46 fs/io_uring.c:9554 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xc14/0x2b40 kernel/exit.c:832 do_group_exit+0x125/0x310 kernel/exit.c:929 __do_sys_exit_group kernel/exit.c:940 [inline] __se_sys_exit_group kernel/exit.c:938 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:938 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7ff71c3a5ae9 Code: Unable to access opcode bytes at RIP 0x7ff71c3a5abf. RSP: 002b:00007ffe8775c9a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 RAX: ffffffffffffffda RBX: 000000000000001e RCX: 00007ff71c3a5ae9 RDX: 00007ff71c35872b RSI: ffffffffffffffbc RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000001 R14: 0000000000000001 R15: 00007ffe8775ca90