------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 5.18.0-rc4-syzkaller #0 Tainted: G S ------------------------------------------------------ rcu_preempt/18 is trying to acquire lock: ffffffff8bd6e0b8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 but task is already holding lock: ffffffff8be04df8 (trace_printk_lock){....}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:385 [inline] ffffffff8be04df8 (trace_printk_lock){....}-{2:2}, at: bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:371 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #3 (trace_printk_lock){....}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 ____bpf_trace_printk kernel/trace/bpf_trace.c:385 [inline] bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:371 ___bpf_prog_run+0x3592/0x77d0 kernel/bpf/core.c:1835 __bpf_prog_run32+0x8a/0xd0 kernel/bpf/core.c:2062 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2022 [inline] bpf_trace_run4+0x124/0x360 kernel/trace/bpf_trace.c:2061 __bpf_trace_sched_switch+0x115/0x160 include/trace/events/sched.h:222 __traceiter_sched_switch+0x68/0xb0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x1543/0x4cc0 kernel/sched/core.c:6385 preempt_schedule_common+0x45/0xc0 kernel/sched/core.c:6553 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 try_to_wake_up+0xa04/0x1800 kernel/sched/core.c:4204 wake_up_process kernel/sched/core.c:4282 [inline] wake_up_q+0x7e/0xf0 kernel/sched/core.c:1029 futex_wake+0x3e9/0x490 kernel/futex/waitwake.c:184 do_futex+0x266/0x300 kernel/futex/syscalls.c:111 __do_sys_futex kernel/futex/syscalls.c:183 [inline] __se_sys_futex kernel/futex/syscalls.c:164 [inline] __x64_sys_futex+0x1b0/0x4a0 kernel/futex/syscalls.c:164 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 -> #2 (&rq->__lock){-.-.}-{2:2}: _raw_spin_lock_nested+0x30/0x40 kernel/locking/spinlock.c:378 raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:554 raw_spin_rq_lock kernel/sched/sched.h:1297 [inline] rq_lock kernel/sched/sched.h:1595 [inline] task_fork_fair+0x68/0x520 kernel/sched/fair.c:11236 sched_cgroup_fork+0x340/0x480 kernel/sched/core.c:4546 copy_process+0x42f0/0x6fe0 kernel/fork.c:2351 kernel_clone+0xe7/0xab0 kernel/fork.c:2639 kernel_thread+0xb5/0xf0 kernel/fork.c:2691 rest_init+0x23/0x3e0 init/main.c:691 start_kernel+0x47f/0x4a0 init/main.c:1140 secondary_startup_64_no_verify+0xc3/0xcb -> #1 (&p->pi_lock){-.-.}-{2:2}: __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 try_to_wake_up+0xaa/0x1800 kernel/sched/core.c:4082 up+0x75/0xb0 kernel/locking/semaphore.c:190 __up_console_sem+0xa4/0xc0 kernel/printk/printk.c:263 console_unlock+0x62c/0xdd0 kernel/printk/printk.c:2794 vga_remove_vgacon drivers/pci/vgaarb.c:189 [inline] vga_remove_vgacon.cold+0x99/0x9e drivers/pci/vgaarb.c:170 drm_aperture_remove_conflicting_pci_framebuffers+0x188/0x230 drivers/gpu/drm/drm_aperture.c:350 virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:61 [inline] virtio_gpu_probe.cold+0x16a/0x189 drivers/gpu/drm/virtio/virtgpu_drv.c:118 virtio_dev_probe+0x577/0x870 drivers/virtio/virtio.c:295 call_driver_probe drivers/base/dd.c:542 [inline] really_probe+0x23e/0xb20 drivers/base/dd.c:621 __driver_probe_device+0x338/0x4d0 drivers/base/dd.c:752 driver_probe_device+0x4c/0x1a0 drivers/base/dd.c:782 __driver_attach+0x22d/0x4e0 drivers/base/dd.c:1141 bus_for_each_dev+0x147/0x1d0 drivers/base/bus.c:301 bus_add_driver+0x41d/0x630 drivers/base/bus.c:618 driver_register+0x220/0x3a0 drivers/base/driver.c:171 do_one_initcall+0x103/0x650 init/main.c:1298 do_initcall_level init/main.c:1371 [inline] do_initcalls init/main.c:1387 [inline] do_basic_setup init/main.c:1406 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1613 kernel_init+0x1a/0x1d0 init/main.c:1502 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 -> #0 ((console_sem).lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3065 [inline] check_prevs_add kernel/locking/lockdep.c:3188 [inline] validate_chain kernel/locking/lockdep.c:3803 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5029 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x40/0x120 kernel/printk/printk.c:246 console_trylock kernel/printk/printk.c:2581 [inline] console_trylock_spinning kernel/printk/printk.c:1856 [inline] vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2271 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2293 __warn_printk+0x9b/0xf3 kernel/panic.c:638 rb_check_timestamp kernel/trace/ring_buffer.c:2734 [inline] rb_add_timestamp kernel/trace/ring_buffer.c:2772 [inline] rb_update_event kernel/trace/ring_buffer.c:2809 [inline] __rb_reserve_next+0x121a/0x1630 kernel/trace/ring_buffer.c:3565 rb_reserve_next_event kernel/trace/ring_buffer.c:3635 [inline] ring_buffer_lock_reserve+0x44f/0xfa0 kernel/trace/ring_buffer.c:3694 __trace_buffer_lock_reserve kernel/trace/trace.c:949 [inline] trace_event_buffer_lock_reserve+0x11e/0x730 kernel/trace/trace.c:2821 trace_event_buffer_reserve+0x248/0x3c0 kernel/trace/trace_events.c:496 trace_event_raw_event_bpf_trace_printk+0xe9/0x1f0 kernel/trace/./bpf_trace.h:11 trace_bpf_trace_printk+0x116/0x220 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0xfa/0x170 kernel/trace/bpf_trace.c:371 ___bpf_prog_run+0x3592/0x77d0 kernel/bpf/core.c:1835 __bpf_prog_run32+0x8a/0xd0 kernel/bpf/core.c:2062 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2022 [inline] bpf_trace_run4+0x124/0x360 kernel/trace/bpf_trace.c:2061 __bpf_trace_sched_switch+0x115/0x160 include/trace/events/sched.h:222 __traceiter_sched_switch+0x68/0xb0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x1543/0x4cc0 kernel/sched/core.c:6385 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1884 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1971 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2144 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 other info that might help us debug this: Chain exists of: (console_sem).lock --> &rq->__lock --> trace_printk_lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(trace_printk_lock); lock(&rq->__lock); lock(trace_printk_lock); lock((console_sem).lock); *** DEADLOCK *** 3 locks held by rcu_preempt/18: #0: ffff88802cc3a098 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2b/0x120 kernel/sched/core.c:554 #1: ffffffff8bd7f5e0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x0/0x360 include/linux/filter.h:628 #2: ffffffff8be04df8 (trace_printk_lock){....}-{2:2}, at: ____bpf_trace_printk kernel/trace/bpf_trace.c:385 [inline] #2: ffffffff8be04df8 (trace_printk_lock){....}-{2:2}, at: bpf_trace_printk+0xcf/0x170 kernel/trace/bpf_trace.c:371 stack backtrace: CPU: 2 PID: 18 Comm: rcu_preempt Tainted: G S 5.18.0-rc4-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2145 check_prev_add kernel/locking/lockdep.c:3065 [inline] check_prevs_add kernel/locking/lockdep.c:3188 [inline] validate_chain kernel/locking/lockdep.c:3803 [inline] __lock_acquire+0x2ac6/0x56c0 kernel/locking/lockdep.c:5029 lock_acquire kernel/locking/lockdep.c:5641 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162 down_trylock+0xe/0x60 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x40/0x120 kernel/printk/printk.c:246 console_trylock kernel/printk/printk.c:2581 [inline] console_trylock_spinning kernel/printk/printk.c:1856 [inline] vprintk_emit+0x162/0x5f0 kernel/printk/printk.c:2271 vprintk+0x80/0x90 kernel/printk/printk_safe.c:50 _printk+0xba/0xed kernel/printk/printk.c:2293 __warn_printk+0x9b/0xf3 kernel/panic.c:638 rb_check_timestamp kernel/trace/ring_buffer.c:2734 [inline] rb_add_timestamp kernel/trace/ring_buffer.c:2772 [inline] rb_update_event kernel/trace/ring_buffer.c:2809 [inline] __rb_reserve_next+0x121a/0x1630 kernel/trace/ring_buffer.c:3565 rb_reserve_next_event kernel/trace/ring_buffer.c:3635 [inline] ring_buffer_lock_reserve+0x44f/0xfa0 kernel/trace/ring_buffer.c:3694 __trace_buffer_lock_reserve kernel/trace/trace.c:949 [inline] trace_event_buffer_lock_reserve+0x11e/0x730 kernel/trace/trace.c:2821 trace_event_buffer_reserve+0x248/0x3c0 kernel/trace/trace_events.c:496 trace_event_raw_event_bpf_trace_printk+0xe9/0x1f0 kernel/trace/./bpf_trace.h:11 trace_bpf_trace_printk+0x116/0x220 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0xfa/0x170 kernel/trace/bpf_trace.c:371 ___bpf_prog_run+0x3592/0x77d0 kernel/bpf/core.c:1835 __bpf_prog_run32+0x8a/0xd0 kernel/bpf/core.c:2062 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2022 [inline] bpf_trace_run4+0x124/0x360 kernel/trace/bpf_trace.c:2061 __bpf_trace_sched_switch+0x115/0x160 include/trace/events/sched.h:222 __traceiter_sched_switch+0x68/0xb0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x1543/0x4cc0 kernel/sched/core.c:6385 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1884 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1971 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2144 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 Delta way too big! 8020330161787334413 ts=8020330481964229010 before=320176894597 after=320176894597 write stamp=8020330481964229010 WARNING: CPU: 2 PID: 18 at kernel/trace/ring_buffer.c:2734 rb_check_timestamp kernel/trace/ring_buffer.c:2734 [inline] WARNING: CPU: 2 PID: 18 at kernel/trace/ring_buffer.c:2734 rb_add_timestamp kernel/trace/ring_buffer.c:2772 [inline] WARNING: CPU: 2 PID: 18 at kernel/trace/ring_buffer.c:2734 rb_update_event kernel/trace/ring_buffer.c:2809 [inline] WARNING: CPU: 2 PID: 18 at kernel/trace/ring_buffer.c:2734 __rb_reserve_next+0x121a/0x1630 kernel/trace/ring_buffer.c:3565 Modules linked in: CPU: 2 PID: 18 Comm: rcu_preempt Tainted: G S 5.18.0-rc4-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 RIP: 0010:rb_check_timestamp kernel/trace/ring_buffer.c:2734 [inline] RIP: 0010:rb_add_timestamp kernel/trace/ring_buffer.c:2772 [inline] RIP: 0010:rb_update_event kernel/trace/ring_buffer.c:2809 [inline] RIP: 0010:__rb_reserve_next+0x121a/0x1630 kernel/trace/ring_buffer.c:3565 Code: 80 3c 01 00 0f 85 98 02 00 00 ff 74 24 40 49 89 d8 4c 89 f1 48 c7 c7 00 17 d1 89 49 8b 74 24 08 4c 8b 4c 24 20 e8 2d da a9 07 <0f> 0b 58 e9 89 fe ff ff e8 39 6c 48 00 e9 0f ee ff ff 48 89 ef e8 RSP: 0018:ffffc9000065f388 EFLAGS: 00010082 RAX: 0000000000000000 RBX: 0000004a8c07b285 RCX: 0000000000000000 RDX: ffff8880118da200 RSI: ffffffff815f3b38 RDI: fffff520000cbe63 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff815ee50e R11: 0000000000000000 R12: ffffc9000065f4c0 R13: ffff888011b30000 R14: 0000004a8c07b285 R15: 0000000000000b40 FS: 0000000000000000(0000) GS:ffff88802cc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fbfc11681b8 CR3: 0000000068ca0000 CR4: 0000000000150ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rb_reserve_next_event kernel/trace/ring_buffer.c:3635 [inline] ring_buffer_lock_reserve+0x44f/0xfa0 kernel/trace/ring_buffer.c:3694 __trace_buffer_lock_reserve kernel/trace/trace.c:949 [inline] trace_event_buffer_lock_reserve+0x11e/0x730 kernel/trace/trace.c:2821 trace_event_buffer_reserve+0x248/0x3c0 kernel/trace/trace_events.c:496 trace_event_raw_event_bpf_trace_printk+0xe9/0x1f0 kernel/trace/./bpf_trace.h:11 trace_bpf_trace_printk+0x116/0x220 kernel/trace/bpf_trace.h:11 ____bpf_trace_printk kernel/trace/bpf_trace.c:388 [inline] bpf_trace_printk+0xfa/0x170 kernel/trace/bpf_trace.c:371 ___bpf_prog_run+0x3592/0x77d0 kernel/bpf/core.c:1835 __bpf_prog_run32+0x8a/0xd0 kernel/bpf/core.c:2062 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline] __bpf_prog_run include/linux/filter.h:628 [inline] bpf_prog_run include/linux/filter.h:635 [inline] __bpf_trace_run kernel/trace/bpf_trace.c:2022 [inline] bpf_trace_run4+0x124/0x360 kernel/trace/bpf_trace.c:2061 __bpf_trace_sched_switch+0x115/0x160 include/trace/events/sched.h:222 __traceiter_sched_switch+0x68/0xb0 include/trace/events/sched.h:222 trace_sched_switch include/trace/events/sched.h:222 [inline] __schedule+0x1543/0x4cc0 kernel/sched/core.c:6385 schedule+0xd2/0x1f0 kernel/sched/core.c:6460 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1884 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1971 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2144 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298