WARNING: possible circular locking dependency detected 6.6.0-rc4-next-20231005-syzkaller #0 Not tainted ------------------------------------------------------ syz-executor.0/5241 is trying to acquire lock: ffff88801f9ba7b8 (&p->pi_lock){-.-.}-{2:2}, at: class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline] ffff88801f9ba7b8 (&p->pi_lock){-.-.}-{2:2}, at: try_to_wake_up+0xb0/0x15d0 kernel/sched/core.c:4213 but task is already holding lock: ffffffff8cb98e18 ((console_sem).lock){-...}-{2:2}, at: up+0x16/0xb0 kernel/locking/semaphore.c:187 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 ((console_sem).lock){-...}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 down_trylock+0x12/0x70 kernel/locking/semaphore.c:139 __down_trylock_console_sem+0x40/0x140 kernel/printk/printk.c:323 console_trylock+0x73/0x130 kernel/printk/printk.c:2652 console_trylock_spinning kernel/printk/printk.c:1924 [inline] vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2303 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2329 pick_eevdf kernel/sched/fair.c:963 [inline] check_preempt_wakeup_fair+0x553/0x640 kernel/sched/fair.c:8108 wakeup_preempt+0x125/0x320 kernel/sched/core.c:2217 ttwu_do_activate+0x24f/0xd90 kernel/sched/core.c:3767 ttwu_queue kernel/sched/core.c:4008 [inline] try_to_wake_up+0x6bc/0x15d0 kernel/sched/core.c:4329 hrtimer_wakeup+0x47/0x60 kernel/time/hrtimer.c:1942 __run_hrtimer kernel/time/hrtimer.c:1688 [inline] __hrtimer_run_queues+0x203/0xc10 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1814 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1063 [inline] __sysvec_apic_timer_interrupt+0x105/0x3f0 arch/x86/kernel/apic/apic.c:1080 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1074 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645 rcu_dynticks_curr_cpu_in_eqs include/linux/context_tracking.h:122 [inline] rcu_is_watching+0x19/0xb0 kernel/rcu/tree.c:699 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x464/0x510 kernel/locking/lockdep.c:5724 rcu_lock_acquire include/linux/rcupdate.h:303 [inline] rcu_read_lock include/linux/rcupdate.h:749 [inline] batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline] batadv_nc_worker+0x16e/0x10e0 net/batman-adv/network-coding.c:719 process_one_work+0x884/0x15c0 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x8b9/0x1290 kernel/workqueue.c:2784 kthread+0x33c/0x440 kernel/kthread.c:388 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 -> #1 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x31/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:558 raw_spin_rq_lock kernel/sched/sched.h:1357 [inline] rq_lock kernel/sched/sched.h:1671 [inline] task_fork_fair+0x70/0x240 kernel/sched/fair.c:12399 sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4799 copy_process+0x4580/0x74b0 kernel/fork.c:2609 kernel_clone+0xfd/0x920 kernel/fork.c:2907 user_mode_thread+0xb4/0xf0 kernel/fork.c:2985 rest_init+0x27/0x2b0 init/main.c:691 arch_call_rest_init+0x13/0x30 init/main.c:823 start_kernel+0x39f/0x480 init/main.c:1068 x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:556 x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:537 secondary_startup_64_no_verify+0x166/0x16b -> #0 (&p->pi_lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline] try_to_wake_up+0xb0/0x15d0 kernel/sched/core.c:4213 up+0x79/0xb0 kernel/locking/semaphore.c:191 __up_console_sem kernel/printk/printk.c:340 [inline] __console_unlock kernel/printk/printk.c:2699 [inline] console_unlock+0x1cf/0x260 kernel/printk/printk.c:3031 vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2304 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2329 ax25_connect+0xcf7/0x1480 net/ax25/af_ax25.c:1269 __sys_connect_file+0x15b/0x1a0 net/socket.c:2050 __sys_connect+0x145/0x170 net/socket.c:2067 __do_sys_connect net/socket.c:2077 [inline] __se_sys_connect net/socket.c:2074 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2074 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd other info that might help us debug this: Chain exists of: &p->pi_lock --> &rq->__lock --> (console_sem).lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((console_sem).lock); lock(&rq->__lock); lock((console_sem).lock); lock(&p->pi_lock); *** DEADLOCK *** 2 locks held by syz-executor.0/5241: #0: ffff88804a1da130 (sk_lock-AF_AX25){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1722 [inline] #0: ffff88804a1da130 (sk_lock-AF_AX25){+.+.}-{0:0}, at: ax25_connect+0x1b7/0x1480 net/ax25/af_ax25.c:1196 #1: ffffffff8cb98e18 ((console_sem).lock){-...}-{2:2}, at: up+0x16/0xb0 kernel/locking/semaphore.c:187 stack backtrace: CPU: 1 PID: 5241 Comm: syz-executor.0 Not tainted 6.6.0-rc4-next-20231005-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 check_noncircular+0x311/0x3f0 kernel/locking/lockdep.c:2187 check_prev_add kernel/locking/lockdep.c:3134 [inline] check_prevs_add kernel/locking/lockdep.c:3253 [inline] validate_chain kernel/locking/lockdep.c:3868 [inline] __lock_acquire+0x2e3d/0x5de0 kernel/locking/lockdep.c:5136 lock_acquire kernel/locking/lockdep.c:5753 [inline] lock_acquire+0x1ae/0x510 kernel/locking/lockdep.c:5718 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x50 kernel/locking/spinlock.c:162 class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:518 [inline] try_to_wake_up+0xb0/0x15d0 kernel/sched/core.c:4213 up+0x79/0xb0 kernel/locking/semaphore.c:191 __up_console_sem kernel/printk/printk.c:340 [inline] __console_unlock kernel/printk/printk.c:2699 [inline] console_unlock+0x1cf/0x260 kernel/printk/printk.c:3031 vprintk_emit+0x17f/0x5f0 kernel/printk/printk.c:2304 vprintk+0x7b/0x90 kernel/printk/printk_safe.c:45 _printk+0xc8/0x100 kernel/printk/printk.c:2329 ax25_connect+0xcf7/0x1480 net/ax25/af_ax25.c:1269 __sys_connect_file+0x15b/0x1a0 net/socket.c:2050 __sys_connect+0x145/0x170 net/socket.c:2067 __do_sys_connect net/socket.c:2077 [inline] __se_sys_connect net/socket.c:2074 [inline] __x64_sys_connect+0x72/0xb0 net/socket.c:2074 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7ff76ce7cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff76dc9e0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007ff76cf9bf80 RCX: 00007ff76ce7cae9 RDX: 0000000000000048 RSI: 00000000200003c0 RDI: 0000000000000004 RBP: 00007ff76cec847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007ff76cf9bf80 R15: 00007ffe5ecaf888