------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 5.15.179-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:7/4275 is trying to acquire lock: ffffffff8c9fbd38 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138 but task is already holding lock: ffff8880b8f2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1692 [inline] ffff8880b8f2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1752 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (hrtimer_bases.lock){-.-.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 lock_hrtimer_base kernel/time/hrtimer.c:173 [inline] hrtimer_start_range_ns+0x105/0xc80 kernel/time/hrtimer.c:1299 hrtimer_start_expires include/linux/hrtimer.h:434 [inline] do_start_rt_bandwidth kernel/sched/rt.c:69 [inline] start_rt_bandwidth kernel/sched/rt.c:80 [inline] inc_rt_group kernel/sched/rt.c:1207 [inline] inc_rt_tasks kernel/sched/rt.c:1251 [inline] __enqueue_rt_entity kernel/sched/rt.c:1321 [inline] enqueue_rt_entity kernel/sched/rt.c:1368 [inline] enqueue_task_rt+0x5a0/0xbf0 kernel/sched/rt.c:1398 enqueue_task+0x19d/0x2e0 kernel/sched/core.c:1976 __sched_setscheduler+0x1396/0x1db0 kernel/sched/core.c:7550 _sched_setscheduler kernel/sched/core.c:7597 [inline] sched_setscheduler_nocheck kernel/sched/core.c:7644 [inline] sched_set_fifo+0x10e/0x1e0 kernel/sched/core.c:7668 drm_vblank_worker_init+0x149/0x190 drivers/gpu/drm/drm_vblank_work.c:263 drm_vblank_init+0x274/0x330 drivers/gpu/drm/drm_vblank.c:551 vkms_create drivers/gpu/drm/vkms/vkms_drv.c:195 [inline] vkms_init+0x330/0x6d0 drivers/gpu/drm/vkms/vkms_drv.c:235 do_one_initcall+0x22b/0x7a0 init/main.c:1302 do_initcall_level+0x157/0x210 init/main.c:1375 do_initcalls+0x49/0x90 init/main.c:1391 kernel_init_freeable+0x425/0x5c0 init/main.c:1615 kernel_init+0x19/0x290 init/main.c:1506 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #3 (&rt_b->rt_runtime_lock){-.-.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock include/linux/spinlock_api_smp.h:142 [inline] _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154 __enable_runtime kernel/sched/rt.c:840 [inline] rq_online_rt+0x123/0x300 kernel/sched/rt.c:2331 set_rq_online kernel/sched/core.c:9036 [inline] sched_cpu_activate+0x508/0x6b0 kernel/sched/core.c:9156 cpuhp_invoke_callback+0x49f/0x820 kernel/cpu.c:191 cpuhp_thread_fun+0x3ee/0x790 kernel/cpu.c:822 smpboot_thread_fn+0x51b/0x9d0 kernel/smpboot.c:164 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #2 (&rq->__lock){-.-.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 _raw_spin_lock_nested+0x2d/0x40 kernel/locking/spinlock.c:368 raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475 raw_spin_rq_lock kernel/sched/sched.h:1326 [inline] rq_lock kernel/sched/sched.h:1621 [inline] task_fork_fair+0x5d/0x350 kernel/sched/fair.c:11499 sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4465 copy_process+0x224a/0x3ef0 kernel/fork.c:2319 kernel_clone+0x210/0x960 kernel/fork.c:2603 kernel_thread+0x12e/0x1a0 kernel/fork.c:2655 rest_init+0x21/0x330 init/main.c:706 start_kernel+0x48c/0x540 init/main.c:1140 secondary_startup_64_no_verify+0xb1/0xbb -> #1 (&p->pi_lock){-.-.}-{2:2}: lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 try_to_wake_up+0xae/0x12c0 kernel/sched/core.c:4029 up+0x6e/0x90 kernel/locking/semaphore.c:190 __up_console_sem+0x11a/0x1e0 kernel/printk/printk.c:256 console_unlock+0x1145/0x12b0 kernel/printk/printk.c:2760 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274 _printk+0xd1/0x120 kernel/printk/printk.c:2299 kauditd_printk_skb kernel/audit.c:549 [inline] kauditd_hold_skb+0x1b5/0x200 kernel/audit.c:584 kauditd_send_queue+0x2a3/0x2f0 kernel/audit.c:769 kauditd_thread+0x6fb/0xae0 kernel/audit.c:893 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #0 ((console_sem).lock){-.-.}-{2:2}: check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239 console_trylock kernel/printk/printk.c:2575 [inline] console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867 vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273 _printk+0xd1/0x120 kernel/printk/printk.c:2299 report_bug+0x1e5/0x2e0 lib/bug.c:195 handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239 exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259 asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:604 copy_from_user_nofault+0x15c/0x1c0 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline] ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline] bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163 bpf_prog_02073d59a3c0f06f+0x3d/0x278 bpf_dispatcher_nop_func include/linux/bpf.h:790 [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:1878 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1915 trace_hrtimer_start include/trace/events/timer.h:199 [inline] debug_activate kernel/time/hrtimer.c:476 [inline] enqueue_hrtimer+0x324/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1769 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 lock_is_held_type+0x14b/0x180 kernel/locking/lockdep.c:5671 lock_is_held include/linux/lockdep.h:287 [inline] ___might_sleep+0xa2/0x6a0 kernel/sched/core.c:9604 inet_twsk_purge+0x11a/0x9e0 net/ipv4/inet_timewait_sock.c:267 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x886/0xc90 net/core/net_namespace.c:618 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 other info that might help us debug this: Chain exists of: (console_sem).lock --> &rt_b->rt_runtime_lock --> hrtimer_bases.lock Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(hrtimer_bases.lock); lock(&rt_b->rt_runtime_lock); lock(hrtimer_bases.lock); lock((console_sem).lock); *** DEADLOCK *** 5 locks held by kworker/u4:7/4275: #0: ffff8880175cd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283 #1: ffffc9000315fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285 #2: ffffffff8dc37e10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x166/0xc90 net/core/net_namespace.c:572 #3: ffff8880b8f2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1692 [inline] #3: ffff8880b8f2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1752 #4: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 4275 Comm: kworker/u4:7 Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: netns cleanup_net Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106 check_noncircular+0x2f8/0x3b0 kernel/locking/lockdep.c:2133 check_prev_add kernel/locking/lockdep.c:3053 [inline] check_prevs_add kernel/locking/lockdep.c:3172 [inline] validate_chain+0x1649/0x5930 kernel/locking/lockdep.c:3788 __lock_acquire+0x1295/0x1ff0 kernel/locking/lockdep.c:5012 lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162 down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138 __down_trylock_console_sem+0x105/0x250 kernel/printk/printk.c:239 console_trylock kernel/printk/printk.c:2575 [inline] console_trylock_spinning+0x8a/0x3f0 kernel/printk/printk.c:1867 vprintk_emit+0xa6/0x150 kernel/printk/printk.c:2273 _printk+0xd1/0x120 kernel/printk/printk.c:2299 report_bug+0x1e5/0x2e0 lib/bug.c:195 handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239 exc_invalid_op+0x16/0x40 arch/x86/kernel/traps.c:259 asm_exc_invalid_op+0x16/0x20 arch/x86/include/asm/idtentry.h:604 RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226 Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 9b b0 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 84 b0 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff RSP: 0018:ffffc90000dd0b00 EFLAGS: 00010046 RAX: ffffffff81aaec3c RBX: 0000000000000000 RCX: ffff888029258000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81aaeb4d R09: fffffbfff2131e19 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000008 R14: 0000000000000000 R15: ffffc90000dd0b68 bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline] ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline] bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163 bpf_prog_02073d59a3c0f06f+0x3d/0x278 bpf_dispatcher_nop_func include/linux/bpf.h:790 [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:1878 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1915 trace_hrtimer_start include/trace/events/timer.h:199 [inline] debug_activate kernel/time/hrtimer.c:476 [inline] enqueue_hrtimer+0x324/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1769 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_is_held_type+0x14b/0x180 kernel/locking/lockdep.c:5671 Code: 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e <41> 5f 5d c3 0f 0b 48 c7 c7 60 2a ab 8a e8 23 11 00 00 65 c7 05 f8 RSP: 0018:ffffc9000315f908 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 000000000000b7c5 RCX: ffff888029258000 RDX: 0000000000000000 RSI: ffffffff8aab3d00 RDI: ffffffff8af9fa80 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1c153f6 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 000000000000b7c4 R14: dffffc0000000000 R15: ffffffff8cb1f540 lock_is_held include/linux/lockdep.h:287 [inline] ___might_sleep+0xa2/0x6a0 kernel/sched/core.c:9604 inet_twsk_purge+0x11a/0x9e0 net/ipv4/inet_timewait_sock.c:267 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x886/0xc90 net/core/net_namespace.c:618 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 WARNING: CPU: 1 PID: 4275 at mm/maccess.c:226 copy_from_user_nofault+0x15c/0x1c0 Modules linked in: CPU: 1 PID: 4275 Comm: kworker/u4:7 Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Workqueue: netns cleanup_net RIP: 0010:copy_from_user_nofault+0x15c/0x1c0 mm/maccess.c:226 Code: db 48 c7 c0 f2 ff ff ff 48 0f 44 c5 eb 0c e8 9b b0 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 84 b0 d5 ff <0f> 0b e9 1e ff ff ff 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c ef fe ff RSP: 0018:ffffc90000dd0b00 EFLAGS: 00010046 RAX: ffffffff81aaec3c RBX: 0000000000000000 RCX: ffff888029258000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81aaeb4d R09: fffffbfff2131e19 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000008 R14: 0000000000000000 R15: ffffc90000dd0b68 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000005d8d1000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bpf_probe_read_user_common kernel/trace/bpf_trace.c:157 [inline] ____bpf_probe_read_user kernel/trace/bpf_trace.c:166 [inline] bpf_probe_read_user+0x26/0x70 kernel/trace/bpf_trace.c:163 bpf_prog_02073d59a3c0f06f+0x3d/0x278 bpf_dispatcher_nop_func include/linux/bpf.h:790 [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:1878 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1915 trace_hrtimer_start include/trace/events/timer.h:199 [inline] debug_activate kernel/time/hrtimer.c:476 [inline] enqueue_hrtimer+0x324/0x390 kernel/time/hrtimer.c:1084 __run_hrtimer kernel/time/hrtimer.c:1705 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1769 handle_softirqs+0x3a7/0x930 kernel/softirq.c:558 __do_softirq kernel/softirq.c:592 [inline] invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x157/0x240 kernel/softirq.c:641 irq_exit_rcu+0x5/0x20 kernel/softirq.c:653 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:lock_is_held_type+0x14b/0x180 kernel/locking/lockdep.c:5671 Code: 00 75 46 41 f7 c4 00 02 00 00 74 01 fb 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 75 3c 89 e8 48 83 c4 10 5b 41 5c 41 5d 41 5e <41> 5f 5d c3 0f 0b 48 c7 c7 60 2a ab 8a e8 23 11 00 00 65 c7 05 f8 RSP: 0018:ffffc9000315f908 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 000000000000b7c5 RCX: ffff888029258000 RDX: 0000000000000000 RSI: ffffffff8aab3d00 RDI: ffffffff8af9fa80 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1c153f6 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 000000000000b7c4 R14: dffffc0000000000 R15: ffffffff8cb1f540 lock_is_held include/linux/lockdep.h:287 [inline] ___might_sleep+0xa2/0x6a0 kernel/sched/core.c:9604 inet_twsk_purge+0x11a/0x9e0 net/ipv4/inet_timewait_sock.c:267 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x886/0xc90 net/core/net_namespace.c:618 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457 kthread+0x3f6/0x4f0 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 ---------------- Code disassembly (best guess): 0: 00 75 46 add %dh,0x46(%rbp) 3: 41 f7 c4 00 02 00 00 test $0x200,%r12d a: 74 01 je 0xd c: fb sti d: 65 48 8b 04 25 28 00 mov %gs:0x28,%rax 14: 00 00 16: 48 3b 44 24 08 cmp 0x8(%rsp),%rax 1b: 75 3c jne 0x59 1d: 89 e8 mov %ebp,%eax 1f: 48 83 c4 10 add $0x10,%rsp 23: 5b pop %rbx 24: 41 5c pop %r12 26: 41 5d pop %r13 28: 41 5e pop %r14 * 2a: 41 5f pop %r15 <-- trapping instruction 2c: 5d pop %rbp 2d: c3 ret 2e: 0f 0b ud2 30: 48 c7 c7 60 2a ab 8a mov $0xffffffff8aab2a60,%rdi 37: e8 23 11 00 00 call 0x115f 3c: 65 gs 3d: c7 .byte 0xc7 3e: 05 .byte 0x5 3f: f8 clc