------------[ cut here ]------------
======================================================
WARNING: possible circular locking dependency detected
6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0 Not tainted
------------------------------------------------------
klogd/4674 is trying to acquire lock:
ffffffff8db9f218 ((console_sem).lock){-...}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139

but task is already holding lock:
ffff88806b23ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #2 (&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:559
       raw_spin_rq_lock kernel/sched/sched.h:1385 [inline]
       rq_lock kernel/sched/sched.h:1699 [inline]
       task_fork_fair+0x70/0x240 kernel/sched/fair.c:12635
       sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4845
       copy_process+0x4106/0x9160 kernel/fork.c:2498
       kernel_clone+0xfd/0x980 kernel/fork.c:2796
       user_mode_thread+0xb4/0xf0 kernel/fork.c:2874
       rest_init+0x23/0x2b0 init/main.c:697
       start_kernel+0x3a3/0x490 init/main.c:1074
       x86_64_start_reservations+0x18/0x30 arch/x86/kernel/head64.c:507
       x86_64_start_kernel+0xb2/0xc0 arch/x86/kernel/head64.c:488
       common_startup_64+0x13e/0x148

-> #1 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162
       class_raw_spinlock_irqsave_constructor include/linux/spinlock.h:553 [inline]
       try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4262
       up+0x79/0xb0 kernel/locking/semaphore.c:191
       __up_console_sem kernel/printk/printk.c:340 [inline]
       __console_unlock kernel/printk/printk.c:2731 [inline]
       console_unlock+0x23e/0x290 kernel/printk/printk.c:3050
       vga_remove_vgacon drivers/pci/vgaarb.c:186 [inline]
       vga_remove_vgacon+0x90/0xd0 drivers/pci/vgaarb.c:167
       __aperture_remove_legacy_vga_devices drivers/video/aperture.c:331 [inline]
       aperture_remove_conflicting_pci_devices+0x17f/0x210 drivers/video/aperture.c:374
       virtio_gpu_pci_quirk drivers/gpu/drm/virtio/virtgpu_drv.c:61 [inline]
       virtio_gpu_probe+0x408/0x4e0 drivers/gpu/drm/virtio/virtgpu_drv.c:92
       virtio_dev_probe+0x5ff/0x9b0 drivers/virtio/virtio.c:311
       call_driver_probe drivers/base/dd.c:578 [inline]
       really_probe+0x23e/0xa90 drivers/base/dd.c:656
       __driver_probe_device+0x1de/0x440 drivers/base/dd.c:798
       driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:828
       __driver_attach+0x283/0x580 drivers/base/dd.c:1214
       bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
       bus_add_driver+0x2ed/0x640 drivers/base/bus.c:673
       driver_register+0x15c/0x4b0 drivers/base/driver.c:246
       do_one_initcall+0x128/0x700 init/main.c:1238
       do_initcall_level init/main.c:1300 [inline]
       do_initcalls init/main.c:1316 [inline]
       do_basic_setup init/main.c:1335 [inline]
       kernel_init_freeable+0x69d/0xca0 init/main.c:1548
       kernel_init+0x1c/0x2b0 init/main.c:1437
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

-> #0 ((console_sem).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:3869 [inline]
       __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
       lock_acquire kernel/locking/lockdep.c:5754 [inline]
       lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0x3a/0x60 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 kernel/printk/printk.c:2684 [inline]
       console_trylock_spinning kernel/printk/printk.c:1958 [inline]
       vprintk_emit kernel/printk/printk.c:2347 [inline]
       vprintk_emit+0xe4/0x5a0 kernel/printk/printk.c:2303
       vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
       _printk+0xc8/0x100 kernel/printk/printk.c:2373
       __report_bug lib/bug.c:195 [inline]
       report_bug+0x4ac/0x580 lib/bug.c:219
       handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
       exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:260
       asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:621
       __local_bh_enable_ip+0xc3/0x120 kernel/softirq.c:362
       spin_unlock_bh include/linux/spinlock.h:396 [inline]
       __sock_map_delete net/core/sock_map.c:424 [inline]
       sock_map_delete_elem+0xfd/0x150 net/core/sock_map.c:446
       ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
       __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
       bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
       __bpf_prog_run include/linux/filter.h:657 [inline]
       bpf_prog_run include/linux/filter.h:664 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
       bpf_trace_run4+0x176/0x460 kernel/trace/bpf_trace.c:2422
       __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
       __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x252c/0x5d00 kernel/sched/core.c:6743
       __schedule_loop kernel/sched/core.c:6823 [inline]
       schedule+0xe7/0x350 kernel/sched/core.c:6838
       syslog_print+0x211/0x5d0 kernel/printk/printk.c:1582
       do_syslog+0x3be/0x6a0 kernel/printk/printk.c:1734
       __do_sys_syslog kernel/printk/printk.c:1826 [inline]
       __se_sys_syslog kernel/printk/printk.c:1824 [inline]
       __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1824
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x6d/0x75

other info that might help us debug this:

Chain exists of:
  (console_sem).lock --> &p->pi_lock --> &rq->__lock

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&rq->__lock);
                               lock(&p->pi_lock);
                               lock(&rq->__lock);
  lock((console_sem).lock);

 *** DEADLOCK ***

2 locks held by klogd/4674:
 #0: ffff88806b23ea58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:559
 #1: ffffffff8dbb14a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:329 [inline]
 #1: ffffffff8dbb14a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:781 [inline]
 #1: ffffffff8dbb14a0 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2380 [inline]
 #1: ffffffff8dbb14a0 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x107/0x460 kernel/trace/bpf_trace.c:2422

stack backtrace:
CPU: 2 PID: 4674 Comm: klogd Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 check_noncircular+0x31a/0x400 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:3869 [inline]
 __lock_acquire+0x2478/0x3b30 kernel/locking/lockdep.c:5137
 lock_acquire kernel/locking/lockdep.c:5754 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0x3a/0x60 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 kernel/printk/printk.c:2684 [inline]
 console_trylock_spinning kernel/printk/printk.c:1958 [inline]
 vprintk_emit kernel/printk/printk.c:2347 [inline]
 vprintk_emit+0xe4/0x5a0 kernel/printk/printk.c:2303
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
 _printk+0xc8/0x100 kernel/printk/printk.c:2373
 __report_bug lib/bug.c:195 [inline]
 report_bug+0x4ac/0x580 lib/bug.c:219
 handle_bug+0x3d/0x70 arch/x86/kernel/traps.c:239
 exc_invalid_op+0x17/0x50 arch/x86/kernel/traps.c:260
 asm_exc_invalid_op+0x1a/0x20 arch/x86/include/asm/idtentry.h:621
RIP: 0010:__local_bh_enable_ip+0xc3/0x120 kernel/softirq.c:362
Code: 00 e8 61 6f 0b 00 e8 0c b7 42 00 fb 65 8b 05 fc 02 b2 7e 85 c0 74 52 5b 5d c3 cc cc cc cc 65 8b 05 be b3 b0 7e 85 c0 75 9e 90 <0f> 0b 90 eb 98 e8 13 b5 42 00 eb 99 48 89 ef e8 a9 f4 19 00 eb a2
RSP: 0018:ffffc9000673f6c8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000201 RCX: 1ffffffff1fc2863
RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff88d477ad
RBP: ffffffff88d477ad R08: 0000000000000000 R09: ffffed1003eff43d
R10: ffff88801f7fa1eb R11: 0000000000000002 R12: ffff88801e93db00
R13: ffffffff81a805c0 R14: 0000000000000000 R15: 0000000000000000
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 __sock_map_delete net/core/sock_map.c:424 [inline]
 sock_map_delete_elem+0xfd/0x150 net/core/sock_map.c:446
 ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run4+0x176/0x460 kernel/trace/bpf_trace.c:2422
 __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x252c/0x5d00 kernel/sched/core.c:6743
 __schedule_loop kernel/sched/core.c:6823 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6838
 syslog_print+0x211/0x5d0 kernel/printk/printk.c:1582
 do_syslog+0x3be/0x6a0 kernel/printk/printk.c:1734
 __do_sys_syslog kernel/printk/printk.c:1826 [inline]
 __se_sys_syslog kernel/printk/printk.c:1824 [inline]
 __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1824
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fa092f79fa7
Code: 73 01 c3 48 8b 0d 81 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffffbd74308 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007fa0931184a0 RCX: 00007fa092f79fa7
RDX: 00000000000003ff RSI: 00007fa0931184a0 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000006 R09: 8b2af3b9680d8567
R10: 0000000000004000 R11: 0000000000000206 R12: 00007fa0931184a0
R13: 00007fa093108212 R14: 00007fa093118670 R15: 00007fa093118670
 </TASK>
WARNING: CPU: 2 PID: 4674 at kernel/softirq.c:362 __local_bh_enable_ip+0xc3/0x120 kernel/softirq.c:362
Modules linked in:
CPU: 2 PID: 4674 Comm: klogd Not tainted 6.9.0-rc1-syzkaller-00178-g317c7bc0ef03 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:__local_bh_enable_ip+0xc3/0x120 kernel/softirq.c:362
Code: 00 e8 61 6f 0b 00 e8 0c b7 42 00 fb 65 8b 05 fc 02 b2 7e 85 c0 74 52 5b 5d c3 cc cc cc cc 65 8b 05 be b3 b0 7e 85 c0 75 9e 90 <0f> 0b 90 eb 98 e8 13 b5 42 00 eb 99 48 89 ef e8 a9 f4 19 00 eb a2
RSP: 0018:ffffc9000673f6c8 EFLAGS: 00010046
RAX: 0000000000000000 RBX: 0000000000000201 RCX: 1ffffffff1fc2863
RDX: 0000000000000000 RSI: 0000000000000201 RDI: ffffffff88d477ad
RBP: ffffffff88d477ad R08: 0000000000000000 R09: ffffed1003eff43d
R10: ffff88801f7fa1eb R11: 0000000000000002 R12: ffff88801e93db00
R13: ffffffff81a805c0 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fa092e18500(0000) GS:ffff88806b200000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000557256f0b300 CR3: 0000000028d1e000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 spin_unlock_bh include/linux/spinlock.h:396 [inline]
 __sock_map_delete net/core/sock_map.c:424 [inline]
 sock_map_delete_elem+0xfd/0x150 net/core/sock_map.c:446
 ___bpf_prog_run+0x3e51/0xae80 kernel/bpf/core.c:1997
 __bpf_prog_run32+0xc1/0x100 kernel/bpf/core.c:2236
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2381 [inline]
 bpf_trace_run4+0x176/0x460 kernel/trace/bpf_trace.c:2422
 __bpf_trace_sched_switch+0x13e/0x190 include/trace/events/sched.h:222
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x252c/0x5d00 kernel/sched/core.c:6743
 __schedule_loop kernel/sched/core.c:6823 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6838
 syslog_print+0x211/0x5d0 kernel/printk/printk.c:1582
 do_syslog+0x3be/0x6a0 kernel/printk/printk.c:1734
 __do_sys_syslog kernel/printk/printk.c:1826 [inline]
 __se_sys_syslog kernel/printk/printk.c:1824 [inline]
 __x64_sys_syslog+0x74/0xb0 kernel/printk/printk.c:1824
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fa092f79fa7
Code: 73 01 c3 48 8b 0d 81 ce 0c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 67 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 51 ce 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007ffffbd74308 EFLAGS: 00000206 ORIG_RAX: 0000000000000067
RAX: ffffffffffffffda RBX: 00007fa0931184a0 RCX: 00007fa092f79fa7
RDX: 00000000000003ff RSI: 00007fa0931184a0 RDI: 0000000000000002
RBP: 0000000000000000 R08: 0000000000000006 R09: 8b2af3b9680d8567
R10: 0000000000004000 R11: 0000000000000206 R12: 00007fa0931184a0
R13: 00007fa093108212 R14: 00007fa093118670 R15: 00007fa093118670
 </TASK>