FAULT_INJECTION: forcing a failure.
name fail_usercopy, interval 1, probability 0, space 0, times 0
======================================================
WARNING: possible circular locking dependency detected
6.11.0-syzkaller-02574-ga430d95c5efa #0 Not tainted
------------------------------------------------------
syz.0.356/6821 is trying to acquire lock:
ffffffff8dda7cb8 ((console_sem).lock){-.-.}-{2:2}, at: down_trylock+0x12/0x70 kernel/locking/semaphore.c:139

but task is already holding lock:
ffff88802b83eb98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:568 [inline]
ffff88802b83eb98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:553

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:560
       raw_spin_rq_lock kernel/sched/sched.h:1415 [inline]
       rq_lock kernel/sched/sched.h:1714 [inline]
       task_fork_fair+0x73/0x250 kernel/sched/fair.c:12710
       sched_cgroup_fork+0x3cf/0x510 kernel/sched/core.c:4633
       copy_process+0x470a/0x6f50 kernel/fork.c:2483
       kernel_clone+0xfd/0x960 kernel/fork.c:2781
       user_mode_thread+0xb4/0xf0 kernel/fork.c:2859
       rest_init+0x23/0x2b0 init/main.c:712
       start_kernel+0x3e4/0x4d0 init/main.c:1105
       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:551 [inline]
       try_to_wake_up+0x9a/0x13e0 kernel/sched/core.c:4051
       up+0x79/0xb0 kernel/locking/semaphore.c:191
       __up_console_sem kernel/printk/printk.c:340 [inline]
       __console_unlock kernel/printk/printk.c:2802 [inline]
       console_unlock+0x23e/0x290 kernel/printk/printk.c:3121
       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+0x16a/0x1e0 drivers/video/aperture.c:369
       bochs_pci_probe+0x101/0x1150 drivers/gpu/drm/tiny/bochs.c:648
       local_pci_probe+0xde/0x1b0 drivers/pci/pci-driver.c:324
       pci_call_probe drivers/pci/pci-driver.c:392 [inline]
       __pci_device_probe drivers/pci/pci-driver.c:417 [inline]
       pci_device_probe+0x29d/0x7b0 drivers/pci/pci-driver.c:451
       call_driver_probe drivers/base/dd.c:578 [inline]
       really_probe+0x23e/0xa90 drivers/base/dd.c:657
       __driver_probe_device+0x1de/0x440 drivers/base/dd.c:799
       driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:829
       __driver_attach+0x283/0x580 drivers/base/dd.c:1215
       bus_for_each_dev+0x13c/0x1d0 drivers/base/bus.c:368
       bus_add_driver+0x2e9/0x690 drivers/base/bus.c:673
       driver_register+0x15c/0x4b0 drivers/base/driver.c:246
       drm_pci_register_driver_if_modeset include/drm/drm_module.h:69 [inline]
       bochs_pci_driver_init+0x67/0x80 drivers/gpu/drm/tiny/bochs.c:732
       do_one_initcall+0x128/0x630 init/main.c:1269
       do_initcall_level init/main.c:1331 [inline]
       do_initcalls init/main.c:1347 [inline]
       do_basic_setup init/main.c:1366 [inline]
       kernel_init_freeable+0x660/0xc50 init/main.c:1580
       kernel_init+0x1c/0x2b0 init/main.c:1469
       ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
       ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

-> #0 ((console_sem).lock){-.-.}-{2:2}:
       check_prev_add kernel/locking/lockdep.c:3133 [inline]
       check_prevs_add kernel/locking/lockdep.c:3252 [inline]
       validate_chain kernel/locking/lockdep.c:3868 [inline]
       __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142
       lock_acquire kernel/locking/lockdep.c:5759 [inline]
       lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
       __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:2755 [inline]
       console_trylock_spinning kernel/printk/printk.c:1958 [inline]
       vprintk_emit+0x3d3/0x600 kernel/printk/printk.c:2347
       vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
       _printk+0xc8/0x100 kernel/printk/printk.c:2373
       fail_dump lib/fault-inject.c:45 [inline]
       should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
       strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
       strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
       bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
       ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
       bpf_probe_read_compat_str+0x131/0x170 kernel/trace/bpf_trace.c:307
       bpf_prog_e3f550b2299101ce+0x40/0x42
       bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
       __bpf_prog_run include/linux/filter.h:691 [inline]
       bpf_prog_run include/linux/filter.h:698 [inline]
       __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
       bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
       __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
       trace_sched_switch include/trace/events/sched.h:222 [inline]
       __schedule+0x17cf/0x5490 kernel/sched/core.c:6526
       preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
       irqentry_exit+0x36/0x90 kernel/entry/common.c:354
       asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
       get_current arch/x86/include/asm/current.h:49 [inline]
       write_comp_data+0x11/0x90 kernel/kcov.c:244
       unwind_get_return_address+0x87/0xe0 arch/x86/kernel/unwind_orc.c:369
       arch_stack_walk+0xc1/0x170 arch/x86/kernel/stacktrace.c:26
       stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
       kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
       kasan_save_track+0x14/0x30 mm/kasan/common.c:68
       unpoison_slab_object mm/kasan/common.c:312 [inline]
       __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338
       kasan_slab_alloc include/linux/kasan.h:201 [inline]
       slab_post_alloc_hook mm/slub.c:3989 [inline]
       slab_alloc_node mm/slub.c:4038 [inline]
       kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4045
       __kernfs_new_node+0xd3/0x890 fs/kernfs/dir.c:624
       kernfs_new_node+0x186/0x240 fs/kernfs/dir.c:700
       __kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1034
       sysfs_add_file_mode_ns+0x1ff/0x3b0 fs/sysfs/file.c:307
       create_files fs/sysfs/group.c:76 [inline]
       internal_create_group+0x565/0xe50 fs/sysfs/group.c:180
       internal_create_groups+0x9d/0x150 fs/sysfs/group.c:220
       device_add_groups drivers/base/core.c:2829 [inline]
       device_add_attrs drivers/base/core.c:2893 [inline]
       device_add+0x6d3/0x1a70 drivers/base/core.c:3636
       netdev_register_kobject+0x187/0x3f0 net/core/net-sysfs.c:2139
       register_netdevice+0x1473/0x1e20 net/core/dev.c:10487
       ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline]
       ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275
       ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline]
       ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline]
       ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733
       ppp_compat_ioctl+0x111/0x400 drivers/net/ppp/ppp_generic.c:1040
       __do_compat_sys_ioctl+0x2bd/0x330 fs/ioctl.c:1007
       do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
       __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
       do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
       entry_SYSENTER_compat_after_hwframe+0x84/0x8e

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 ***

4 locks held by syz.0.356/6821:
 #0: ffffffff8ef0a7e8 (ppp_mutex){+.+.}-{3:3}, at: ppp_ioctl+0xc3/0x2590 drivers/net/ppp/ppp_generic.c:729
 #1: ffffffff8faac368 (rtnl_mutex){+.+.}-{3:3}, at: ppp_create_interface drivers/net/ppp/ppp_generic.c:3346 [inline]
 #1: ffffffff8faac368 (rtnl_mutex){+.+.}-{3:3}, at: ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline]
 #1: ffffffff8faac368 (rtnl_mutex){+.+.}-{3:3}, at: ppp_ioctl+0x17d8/0x2590 drivers/net/ppp/ppp_generic.c:733
 #2: ffff88802b83eb98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested kernel/sched/core.c:568 [inline]
 #2: ffff88802b83eb98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x7e/0x130 kernel/sched/core.c:553
 #3: ffffffff8ddb9b60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:326 [inline]
 #3: ffffffff8ddb9b60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #3: ffffffff8ddb9b60 (rcu_read_lock){....}-{1:2}, at: __bpf_trace_run kernel/trace/bpf_trace.c:2405 [inline]
 #3: ffffffff8ddb9b60 (rcu_read_lock){....}-{1:2}, at: bpf_trace_run4+0x1d6/0x5a0 kernel/trace/bpf_trace.c:2449

stack backtrace:
CPU: 2 UID: 0 PID: 6821 Comm: syz.0.356 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 check_noncircular+0x31a/0x400 kernel/locking/lockdep.c:2186
 check_prev_add kernel/locking/lockdep.c:3133 [inline]
 check_prevs_add kernel/locking/lockdep.c:3252 [inline]
 validate_chain kernel/locking/lockdep.c:3868 [inline]
 __lock_acquire+0x24ed/0x3cb0 kernel/locking/lockdep.c:5142
 lock_acquire kernel/locking/lockdep.c:5759 [inline]
 lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5724
 __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:2755 [inline]
 console_trylock_spinning kernel/printk/printk.c:1958 [inline]
 vprintk_emit+0x3d3/0x600 kernel/printk/printk.c:2347
 vprintk+0x7f/0xa0 kernel/printk/printk_safe.c:45
 _printk+0xc8/0x100 kernel/printk/printk.c:2373
 fail_dump lib/fault-inject.c:45 [inline]
 should_fail_ex+0x46c/0x5b0 lib/fault-inject.c:153
 strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
 bpf_probe_read_compat_str+0x131/0x170 kernel/trace/bpf_trace.c:307
 bpf_prog_e3f550b2299101ce+0x40/0x42
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x17cf/0x5490 kernel/sched/core.c:6526
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:245
Code: cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 6f b3 78 7e <65> 8b 05 70 b3 78 7e a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00
RSP: 0018:ffffc900076f72d8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc900076f7308 RCX: ffffffff813c97c7
RDX: ffff888040ee4880 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc900076f7350
R13: ffffffff8176dea0 R14: ffffc900076f73c8 R15: ffff888040ee4880
 unwind_get_return_address+0x87/0xe0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xc1/0x170 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3989 [inline]
 slab_alloc_node mm/slub.c:4038 [inline]
 kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4045
 __kernfs_new_node+0xd3/0x890 fs/kernfs/dir.c:624
 kernfs_new_node+0x186/0x240 fs/kernfs/dir.c:700
 __kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1034
 sysfs_add_file_mode_ns+0x1ff/0x3b0 fs/sysfs/file.c:307
 create_files fs/sysfs/group.c:76 [inline]
 internal_create_group+0x565/0xe50 fs/sysfs/group.c:180
 internal_create_groups+0x9d/0x150 fs/sysfs/group.c:220
 device_add_groups drivers/base/core.c:2829 [inline]
 device_add_attrs drivers/base/core.c:2893 [inline]
 device_add+0x6d3/0x1a70 drivers/base/core.c:3636
 netdev_register_kobject+0x187/0x3f0 net/core/net-sysfs.c:2139
 register_netdevice+0x1473/0x1e20 net/core/dev.c:10487
 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline]
 ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275
 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline]
 ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline]
 ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733
 ppp_compat_ioctl+0x111/0x400 drivers/net/ppp/ppp_generic.c:1040
 __do_compat_sys_ioctl+0x2bd/0x330 fs/ioctl.c:1007
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f56579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f56b556c EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000c004743e
RDX: 0000000020001439 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
CPU: 2 UID: 0 PID: 6821 Comm: syz.0.356 Not tainted 6.11.0-syzkaller-02574-ga430d95c5efa #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 fail_dump lib/fault-inject.c:52 [inline]
 should_fail_ex+0x497/0x5b0 lib/fault-inject.c:153
 strncpy_from_user+0x38/0x320 lib/strncpy_from_user.c:118
 strncpy_from_user_nofault+0x7f/0x180 mm/maccess.c:186
 bpf_probe_read_user_str_common kernel/trace/bpf_trace.c:216 [inline]
 ____bpf_probe_read_compat_str kernel/trace/bpf_trace.c:311 [inline]
 bpf_probe_read_compat_str+0x131/0x170 kernel/trace/bpf_trace.c:307
 bpf_prog_e3f550b2299101ce+0x40/0x42
 bpf_dispatcher_nop_func include/linux/bpf.h:1243 [inline]
 __bpf_prog_run include/linux/filter.h:691 [inline]
 bpf_prog_run include/linux/filter.h:698 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:2406 [inline]
 bpf_trace_run4+0x245/0x5a0 kernel/trace/bpf_trace.c:2449
 __traceiter_sched_switch+0x6c/0xc0 include/trace/events/sched.h:222
 trace_sched_switch include/trace/events/sched.h:222 [inline]
 __schedule+0x17cf/0x5490 kernel/sched/core.c:6526
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:26 [inline]
RIP: 0010:check_kcov_mode kernel/kcov.c:182 [inline]
RIP: 0010:write_comp_data+0x11/0x90 kernel/kcov.c:245
Code: cc cc cc cc 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 49 89 d2 49 89 f8 49 89 f1 65 48 8b 15 6f b3 78 7e <65> 8b 05 70 b3 78 7e a9 00 01 ff 00 74 1d f6 c4 01 74 67 a9 00 00
RSP: 0018:ffffc900076f72d8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffc900076f7308 RCX: ffffffff813c97c7
RDX: ffff888040ee4880 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc900076f7350
R13: ffffffff8176dea0 R14: ffffc900076f73c8 R15: ffff888040ee4880
 unwind_get_return_address+0x87/0xe0 arch/x86/kernel/unwind_orc.c:369
 arch_stack_walk+0xc1/0x170 arch/x86/kernel/stacktrace.c:26
 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3989 [inline]
 slab_alloc_node mm/slub.c:4038 [inline]
 kmem_cache_alloc_noprof+0x121/0x2f0 mm/slub.c:4045
 __kernfs_new_node+0xd3/0x890 fs/kernfs/dir.c:624
 kernfs_new_node+0x186/0x240 fs/kernfs/dir.c:700
 __kernfs_create_file+0x53/0x350 fs/kernfs/file.c:1034
 sysfs_add_file_mode_ns+0x1ff/0x3b0 fs/sysfs/file.c:307
 create_files fs/sysfs/group.c:76 [inline]
 internal_create_group+0x565/0xe50 fs/sysfs/group.c:180
 internal_create_groups+0x9d/0x150 fs/sysfs/group.c:220
 device_add_groups drivers/base/core.c:2829 [inline]
 device_add_attrs drivers/base/core.c:2893 [inline]
 device_add+0x6d3/0x1a70 drivers/base/core.c:3636
 netdev_register_kobject+0x187/0x3f0 net/core/net-sysfs.c:2139
 register_netdevice+0x1473/0x1e20 net/core/dev.c:10487
 ppp_unit_register drivers/net/ppp/ppp_generic.c:1219 [inline]
 ppp_dev_configure+0x9aa/0xc90 drivers/net/ppp/ppp_generic.c:1275
 ppp_create_interface drivers/net/ppp/ppp_generic.c:3348 [inline]
 ppp_unattached_ioctl drivers/net/ppp/ppp_generic.c:1060 [inline]
 ppp_ioctl+0x17eb/0x2590 drivers/net/ppp/ppp_generic.c:733
 ppp_compat_ioctl+0x111/0x400 drivers/net/ppp/ppp_generic.c:1040
 __do_compat_sys_ioctl+0x2bd/0x330 fs/ioctl.c:1007
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0x73/0x120 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x32/0x80 arch/x86/entry/common.c:411
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e
RIP: 0023:0xf7f56579
Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f56b556c EFLAGS: 00000296 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00000000c004743e
RDX: 0000000020001439 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>
----------------
Code disassembly (best guess):
   0:	cc                   	int3
   1:	cc                   	int3
   2:	cc                   	int3
   3:	cc                   	int3
   4:	0f 1f 44 00 00       	nopl   0x0(%rax,%rax,1)
   9:	90                   	nop
   a:	90                   	nop
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	49 89 d2             	mov    %rdx,%r10
  1c:	49 89 f8             	mov    %rdi,%r8
  1f:	49 89 f1             	mov    %rsi,%r9
  22:	65 48 8b 15 6f b3 78 	mov    %gs:0x7e78b36f(%rip),%rdx        # 0x7e78b399
  29:	7e
* 2a:	65 8b 05 70 b3 78 7e 	mov    %gs:0x7e78b370(%rip),%eax        # 0x7e78b3a1 <-- trapping instruction
  31:	a9 00 01 ff 00       	test   $0xff0100,%eax
  36:	74 1d                	je     0x55
  38:	f6 c4 01             	test   $0x1,%ah
  3b:	74 67                	je     0xa4
  3d:	a9                   	.byte 0xa9