------------[ cut here ]------------ ====================================================== WARNING: possible circular locking dependency detected 5.15.158-syzkaller #0 Not tainted ------------------------------------------------------ swapper/1/0 is trying to acquire lock: ffffffff8c7fc338 ((console_sem).lock){..-.}-{2:2}, at: down_trylock+0x1c/0xa0 kernel/locking/semaphore.c:138 but task is already holding lock: ffff8880b9b2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1690 [inline] ffff8880b9b2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1750 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+0xd8/0xc50 kernel/time/hrtimer.c:1297 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+0x181/0x3a0 kernel/sched/core.c:1977 __sched_setscheduler+0x13bf/0x1e20 kernel/sched/core.c:7551 _sched_setscheduler kernel/sched/core.c:7598 [inline] sched_setscheduler_nocheck kernel/sched/core.c:7645 [inline] sched_set_fifo+0x10e/0x1e0 kernel/sched/core.c:7669 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:300 -> #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:9037 [inline] sched_cpu_activate+0x508/0x6b0 kernel/sched/core.c:9144 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:300 -> #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:11480 sched_cgroup_fork+0x2d3/0x330 kernel/sched/core.c:4466 copy_process+0x224a/0x3ef0 kernel/fork.c:2320 kernel_clone+0x210/0x960 kernel/fork.c:2604 kernel_thread+0x168/0x1e0 kernel/fork.c:2656 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/0x1300 kernel/sched/core.c:4030 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 check_stack_usage kernel/exit.c:764 [inline] do_exit+0x1a91/0x2480 kernel/exit.c:915 call_usermodehelper_exec_async+0x368/0x370 kernel/umh.c:125 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:300 -> #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:566 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_5f6df167d0cc17e3+0x3d/0x358 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:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 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:1703 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1767 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 tick_nohz_idle_enter+0x22c/0x2f0 kernel/time/tick-sched.c:1156 do_idle+0xa7/0x670 kernel/sched/idle.c:280 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb 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 *** 2 locks held by swapper/1/0: #0: ffff8880b9b2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1690 [inline] #0: ffff8880b9b2a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x662/0xcf0 kernel/time/hrtimer.c:1750 #1: ffffffff8c91fae0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311 stack backtrace: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 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:566 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 7b c4 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 64 c4 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:ffffc90000dd0b08 EFLAGS: 00010046 RAX: ffffffff81aa985c RBX: 0000000000000000 RCX: ffff888012a00000 RDX: 0000000080000103 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81aa976d R09: fffffbfff1f7ee19 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_5f6df167d0cc17e3+0x3d/0x358 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:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 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:1703 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1767 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:tick_nohz_idle_enter+0x22c/0x2f0 kernel/time/tick-sched.c:1156 Code: 00 4d 89 3c 24 42 0f b6 04 2b 84 c0 0f 85 a2 00 00 00 41 80 0e 04 e8 53 c9 e6 ff e8 ce cc 13 00 fb 48 c7 44 24 20 0e 36 e0 45 <48> 8b 44 24 18 49 c7 44 05 00 00 00 00 00 65 48 8b 04 25 28 00 00 RSP: 0018:ffffc90000d67c80 EFLAGS: 00000282 RAX: 53e11105a9ebee00 RBX: 1ffff11017365582 RCX: ffffffff913eef03 RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f600 RBP: ffffc90000d67d30 R08: ffffffff8186dcf0 R09: ffffffff8f5fa048 R10: ffffffff8f5fa058 R11: ffffffff8f5fa050 R12: ffff8880b9b2ac40 R13: dffffc0000000000 R14: ffff8880b9b2ac14 R15: 0000000d6349caa4 do_idle+0xa7/0x670 kernel/sched/idle.c:280 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb WARNING: CPU: 1 PID: 0 at mm/maccess.c:226 copy_from_user_nofault+0x15c/0x1c0 Modules linked in: CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 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 7b c4 d5 ff 48 c7 c0 f2 ff ff ff 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 64 c4 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:ffffc90000dd0b08 EFLAGS: 00010046 RAX: ffffffff81aa985c RBX: 0000000000000000 RCX: ffff888012a00000 RDX: 0000000080000103 RSI: 0000000000000000 RDI: 0000000000000000 RBP: dffffc0000000000 R08: ffffffff81aa976d R09: fffffbfff1f7ee19 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000 R13: 0000000000000008 R14: 0000000000000000 R15: ffffc90000dd0b68 FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055555594cda8 CR3: 00000000775a8000 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_5f6df167d0cc17e3+0x3d/0x358 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:1880 [inline] bpf_trace_run2+0x19e/0x340 kernel/trace/bpf_trace.c:1917 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:1703 [inline] __hrtimer_run_queues+0x6b6/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_run_softirq+0x196/0x2c0 kernel/time/hrtimer.c:1767 __do_softirq+0x3b3/0x93a kernel/softirq.c:558 invoke_softirq kernel/softirq.c:432 [inline] __irq_exit_rcu+0x155/0x240 kernel/softirq.c:637 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:tick_nohz_idle_enter+0x22c/0x2f0 kernel/time/tick-sched.c:1156 Code: 00 4d 89 3c 24 42 0f b6 04 2b 84 c0 0f 85 a2 00 00 00 41 80 0e 04 e8 53 c9 e6 ff e8 ce cc 13 00 fb 48 c7 44 24 20 0e 36 e0 45 <48> 8b 44 24 18 49 c7 44 05 00 00 00 00 00 65 48 8b 04 25 28 00 00 RSP: 0018:ffffc90000d67c80 EFLAGS: 00000282 RAX: 53e11105a9ebee00 RBX: 1ffff11017365582 RCX: ffffffff913eef03 RDX: dffffc0000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f600 RBP: ffffc90000d67d30 R08: ffffffff8186dcf0 R09: ffffffff8f5fa048 R10: ffffffff8f5fa058 R11: ffffffff8f5fa050 R12: ffff8880b9b2ac40 R13: dffffc0000000000 R14: ffff8880b9b2ac14 R15: 0000000d6349caa4 do_idle+0xa7/0x670 kernel/sched/idle.c:280 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb ---------------- Code disassembly (best guess): 0: 00 4d 89 add %cl,-0x77(%rbp) 3: 3c 24 cmp $0x24,%al 5: 42 0f b6 04 2b movzbl (%rbx,%r13,1),%eax a: 84 c0 test %al,%al c: 0f 85 a2 00 00 00 jne 0xb4 12: 41 80 0e 04 orb $0x4,(%r14) 16: e8 53 c9 e6 ff call 0xffe6c96e 1b: e8 ce cc 13 00 call 0x13ccee 20: fb sti 21: 48 c7 44 24 20 0e 36 movq $0x45e0360e,0x20(%rsp) 28: e0 45 * 2a: 48 8b 44 24 18 mov 0x18(%rsp),%rax <-- trapping instruction 2f: 49 c7 44 05 00 00 00 movq $0x0,0x0(%r13,%rax,1) 36: 00 00 38: 65 gs 39: 48 rex.W 3a: 8b .byte 0x8b 3b: 04 25 add $0x25,%al 3d: 28 00 sub %al,(%rax)