syzbot


WARNING in hrtimer_start_range_ns

Status: upstream: reported C repro on 2025/09/05 20:25
Reported-by: syzbot+ba7c396c3788b490c6a3@syzkaller.appspotmail.com
First crash: 8d11h, last: 7d20h

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 1 PID: 3561 at mm/maccess.c:226 copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226
Modules linked in:
CPU: 1 PID: 3561 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:copy_from_user_nofault+0x160/0x1c0 mm/maccess.c:226
Code: 24 45 31 f6 31 ff 89 de e8 ed f6 d8 ff 85 db 48 c7 c0 f2 ff ff ff 49 0f 44 c6 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 70 f3 d8 ff <0f> 0b e9 1c ff ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c ea fe
RSP: 0018:ffffc90000dd0ba0 EFLAGS: 00010006
RAX: ffffffff819ed740 RBX: 0000000000000008 RCX: ffff88807cd01dc0

======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Not tainted
------------------------------------------------------
udevd/3561 is trying to acquire lock:
ffffffff8c110ec0 (console_owner){-...}-{0:0}, at: console_trylock_spinning+0x150/0x350 kernel/printk/printk.c:1879

but task is already holding lock:
ffff8880b912a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1694 [inline]
ffff8880b912a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5ff/0xc40 kernel/time/hrtimer.c:1754

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #6 (hrtimer_bases.lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
       lock_hrtimer_base kernel/time/hrtimer.c:168 [inline]
       hrtimer_start_range_ns+0xff/0xc20 kernel/time/hrtimer.c:1289
       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+0x60c/0xc00 kernel/sched/rt.c:1398
       enqueue_task+0x182/0x2b0 kernel/sched/core.c:1996
       __sched_setscheduler+0x1379/0x1be0 kernel/sched/core.c:7570
       _sched_setscheduler kernel/sched/core.c:7617 [inline]
       sched_setscheduler_nocheck kernel/sched/core.c:7664 [inline]
       sched_set_fifo+0xbc/0x120 kernel/sched/core.c:7688
       drm_vblank_worker_init+0x149/0x1a0 drivers/gpu/drm/drm_vblank_work.c:263
       drm_vblank_init+0x265/0x330 drivers/gpu/drm/drm_vblank.c:551
       vkms_create drivers/gpu/drm/vkms/vkms_drv.c:195 [inline]
       vkms_init+0x31a/0x700 drivers/gpu/drm/vkms/vkms_drv.c:233
       do_one_initcall+0x1ee/0x680 init/main.c:1302
       do_initcall_level+0x137/0x1f0 init/main.c:1375
       do_initcalls+0x4b/0x90 init/main.c:1391
       kernel_init_freeable+0x3ce/0x560 init/main.c:1615
       kernel_init+0x19/0x1b0 init/main.c:1506
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #5 (&rt_b->rt_runtime_lock){-...}-{2:2}:
       __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+0x125/0x310 kernel/sched/rt.c:2331
       set_rq_online kernel/sched/core.c:9056 [inline]
       sched_cpu_activate+0x4ae/0x650 kernel/sched/core.c:9176
       cpuhp_invoke_callback+0x431/0x830 kernel/cpu.c:191
       cpuhp_thread_fun+0x39a/0x7d0 kernel/cpu.c:822
       smpboot_thread_fn+0x4f6/0x970 kernel/smpboot.c:164
       kthread+0x436/0x520 kernel/kthread.c:334
       ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

-> #4 (&rq->__lock){-.-.}-{2:2}:
       _raw_spin_lock_nested+0x2e/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+0x5c/0x350 kernel/sched/fair.c:11499
       sched_cgroup_fork+0x2c6/0x320 kernel/sched/core.c:4485
       copy_process+0x22d1/0x3e00 kernel/fork.c:2395
       kernel_clone+0x219/0x930 kernel/fork.c:2679
       kernel_thread+0xc8/0x120 kernel/fork.c:2731
       rest_init+0x21/0x330 init/main.c:706
       start_kernel+0x486/0x530 init/main.c:1140
       secondary_startup_64_no_verify+0xb1/0xbb

-> #3 (&p->pi_lock){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
       try_to_wake_up+0x5c/0x1050 kernel/sched/core.c:4049
       __wake_up_common+0x2a4/0x4e0 kernel/sched/wait.c:108
       __wake_up_common_lock kernel/sched/wait.c:138 [inline]
       __wake_up+0x108/0x180 kernel/sched/wait.c:157
       tty_port_default_wakeup+0xa5/0xf0 drivers/tty/tty_port.c:51
       serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1828
       serial8250_handle_irq+0x519/0x610 drivers/tty/serial/8250/8250_port.c:1924
       serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1941
       serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:127
       __handle_irq_event_percpu+0x291/0x9b0 kernel/irq/handle.c:156
       handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
       handle_irq_event+0xa5/0x220 kernel/irq/handle.c:213
       handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:233 [inline]
       __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
       common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
       asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:667
       on_stack arch/x86/include/asm/stacktrace.h:-1 [inline]
       unwind_next_frame+0x11e8/0x1d90 arch/x86/kernel/unwind_orc.c:609
       arch_stack_walk+0x10c/0x140 arch/x86/kernel/stacktrace.c:25
       stack_trace_save+0x98/0xe0 kernel/stacktrace.c:122
       kasan_save_stack mm/kasan/common.c:38 [inline]
       kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
       kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
       ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
       kasan_slab_free include/linux/kasan.h:230 [inline]
       slab_free_hook mm/slub.c:1705 [inline]
       slab_free_freelist_hook+0xea/0x170 mm/slub.c:1731
       slab_free mm/slub.c:3499 [inline]
       kmem_cache_free+0x8f/0x210 mm/slub.c:3515
       remove_vma mm/mmap.c:188 [inline]
       exit_mmap+0x4d8/0x5f0 mm/mmap.c:3227
       __mmput+0x115/0x3b0 kernel/fork.c:1127
       exec_mmap+0x4d1/0x5c0 fs/exec.c:1035
       begin_new_exec+0x7e8/0x1160 fs/exec.c:1293
       load_elf_binary+0x98e/0x2890 fs/binfmt_elf.c:1001
       search_binary_handler fs/exec.c:1742 [inline]
       exec_binprm fs/exec.c:1783 [inline]
       bprm_execve+0xa92/0x17d0 fs/exec.c:1852
       do_execveat_common+0x51e/0x6d0 fs/exec.c:1957
       do_execve fs/exec.c:2027 [inline]
       __do_sys_execve fs/exec.c:2103 [inline]
       __se_sys_execve fs/exec.c:2098 [inline]
       __x64_sys_execve+0x8e/0xa0 fs/exec.c:2098
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #2 (&tty->write_wait){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
       __wake_up_common_lock kernel/sched/wait.c:137 [inline]
       __wake_up+0xed/0x180 kernel/sched/wait.c:157
       tty_port_default_wakeup+0xa5/0xf0 drivers/tty/tty_port.c:51
       serial8250_tx_chars+0x629/0x830 drivers/tty/serial/8250/8250_port.c:1828
       serial8250_handle_irq+0x519/0x610 drivers/tty/serial/8250/8250_port.c:1924
       serial8250_default_handle_irq+0xb4/0x1a0 drivers/tty/serial/8250/8250_port.c:1941
       serial8250_interrupt+0x9b/0x1c0 drivers/tty/serial/8250/8250_core.c:127
       __handle_irq_event_percpu+0x291/0x9b0 kernel/irq/handle.c:156
       handle_irq_event_percpu kernel/irq/handle.c:196 [inline]
       handle_irq_event+0xa5/0x220 kernel/irq/handle.c:213
       handle_edge_irq+0x243/0xb20 kernel/irq/chip.c:819
       generic_handle_irq_desc include/linux/irqdesc.h:158 [inline]
       handle_irq arch/x86/kernel/irq.c:233 [inline]
       __common_interrupt+0xd7/0x1e0 arch/x86/kernel/irq.c:252
       common_interrupt+0xb0/0xd0 arch/x86/kernel/irq.c:242
       asm_common_interrupt+0x22/0x40 arch/x86/include/asm/idtentry.h:667
       __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
       _raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194
       spin_unlock_irqrestore include/linux/spinlock.h:418 [inline]
       uart_write+0x62f/0x880 drivers/tty/serial/serial_core.c:592
       process_output_block drivers/tty/n_tty.c:592 [inline]
       n_tty_write+0xd21/0x1210 drivers/tty/n_tty.c:2339
       do_tty_write drivers/tty/tty_io.c:1038 [inline]
       file_tty_write+0x557/0x910 drivers/tty/tty_io.c:1110
       call_write_iter include/linux/fs.h:2172 [inline]
       new_sync_write fs/read_write.c:507 [inline]
       vfs_write+0x712/0xd00 fs/read_write.c:594
       ksys_write+0x14d/0x250 fs/read_write.c:647
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

-> #1 (&port_lock_key){-.-.}-{2:2}:
       __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
       _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162
       serial8250_console_write+0x170/0xf80 drivers/tty/serial/8250/8250_port.c:3362
       call_console_drivers kernel/printk/printk.c:-1 [inline]
       console_unlock+0xc86/0x1200 kernel/printk/printk.c:2744
       vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274
       _printk+0xcc/0x110 kernel/printk/printk.c:2299
       register_console+0x682/0x960 kernel/printk/printk.c:3107
       univ8250_console_init+0x41/0x50 drivers/tty/serial/8250/8250_core.c:690
       console_init+0x177/0x5d0 kernel/printk/printk.c:3207
       start_kernel+0x2f9/0x530 init/main.c:1076
       secondary_startup_64_no_verify+0xb1/0xbb

-> #0 (console_owner){-...}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3053 [inline]
       check_prevs_add kernel/locking/lockdep.c:3172 [inline]
       validate_chain kernel/locking/lockdep.c:3788 [inline]
       __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
       lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
       console_trylock_spinning+0x170/0x350 kernel/printk/printk.c:1896
       vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273
       _printk+0xcc/0x110 kernel/printk/printk.c:2299
       __show_regs+0xcb/0x500 arch/x86/kernel/process_64.c:81
       show_regs+0x32/0x60 arch/x86/kernel/dumpstack.c:471
       __warn+0x15e/0x2b0 kernel/panic.c:678
       report_bug+0x1b7/0x2e0 lib/bug.c:199
       handle_bug+0x3a/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+0x160/0x1c0 mm/maccess.c:226
       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/0x458
       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+0x15b/0x2d0 kernel/trace/bpf_trace.c:1915
       trace_hrtimer_start include/trace/events/timer.h:199 [inline]
       debug_activate kernel/time/hrtimer.c:466 [inline]
       enqueue_hrtimer+0x314/0x370 kernel/time/hrtimer.c:1074
       __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
       __hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1754
       hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
       local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
       __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
       instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
       sysvec_apic_timer_interrupt+0x9b/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+0x13a/0x190 kernel/locking/lockdep.c:5671
       lock_is_held include/linux/lockdep.h:287 [inline]
       ___might_sleep+0xf2/0x600 kernel/sched/core.c:9624
       might_alloc include/linux/sched/mm.h:209 [inline]
       slab_pre_alloc_hook+0x42/0xc0 mm/slab.h:492
       slab_alloc_node mm/slub.c:3134 [inline]
       slab_alloc mm/slub.c:3228 [inline]
       kmem_cache_alloc+0x3d/0x290 mm/slub.c:3233
       getname_flags+0xb5/0x500 fs/namei.c:138
       do_sys_openat2+0xcf/0x4a0 fs/open.c:1247
       do_sys_open fs/open.c:1269 [inline]
       __do_sys_openat fs/open.c:1285 [inline]
       __se_sys_openat fs/open.c:1280 [inline]
       __x64_sys_openat+0x135/0x160 fs/open.c:1280
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x66/0xd0

other info that might help us debug this:

Chain exists of:
  console_owner --> &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_owner);

 *** DEADLOCK ***

2 locks held by udevd/3561:
 #0: ffff8880b912a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __run_hrtimer kernel/time/hrtimer.c:1694 [inline]
 #0: ffff8880b912a218 (hrtimer_bases.lock){-.-.}-{2:2}, at: __hrtimer_run_queues+0x5ff/0xc40 kernel/time/hrtimer.c:1754
 #1: ffffffff8c11c460 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x5/0x30 include/linux/rcupdate.h:311

stack backtrace:
CPU: 1 PID: 3561 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <IRQ>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 check_noncircular+0x274/0x310 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 kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire+0x2c33/0x7c60 kernel/locking/lockdep.c:5012
 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623
 console_trylock_spinning+0x170/0x350 kernel/printk/printk.c:1896
 vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273
 _printk+0xcc/0x110 kernel/printk/printk.c:2299
 __show_regs+0xcb/0x500 arch/x86/kernel/process_64.c:81
 show_regs+0x32/0x60 arch/x86/kernel/dumpstack.c:471
 __warn+0x15e/0x2b0 kernel/panic.c:678
 report_bug+0x1b7/0x2e0 lib/bug.c:199
 handle_bug+0x3a/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+0x160/0x1c0 mm/maccess.c:226
Code: 24 45 31 f6 31 ff 89 de e8 ed f6 d8 ff 85 db 48 c7 c0 f2 ff ff ff 49 0f 44 c6 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 70 f3 d8 ff <0f> 0b e9 1c ff ff ff 44 89 e1 80 e1 07 80 c1 03 38 c1 0f 8c ea fe
RSP: 0018:ffffc90000dd0ba0 EFLAGS: 00010006
RAX: ffffffff819ed740 RBX: 0000000000000008 RCX: ffff88807cd01dc0
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ff7619
R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: ffff88807cd03548
R13: dffffc0000000000 R14: ffffc90000dd0c08 R15: 0000000000000000
 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/0x458
 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+0x15b/0x2d0 kernel/trace/bpf_trace.c:1915
 trace_hrtimer_start include/trace/events/timer.h:199 [inline]
 debug_activate kernel/time/hrtimer.c:466 [inline]
 enqueue_hrtimer+0x314/0x370 kernel/time/hrtimer.c:1074
 __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
 __hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 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
RSP: 0018:ffffc900012dfb98 EFLAGS: 00000206
RAX: d3b510027ebaa800 RBX: ffff88807cd01dc0 RCX: d3b510027ebaa800
RDX: 0000000000000000 RSI: ffffffff8a0b28c0 RDI: ffffffff8a59a240
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad31be
R10: fffffbfff1ad31be R11: 1ffffffff1ad31bd R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8c11c520 R15: 00000000ffffffff
 lock_is_held include/linux/lockdep.h:287 [inline]
 ___might_sleep+0xf2/0x600 kernel/sched/core.c:9624
 might_alloc include/linux/sched/mm.h:209 [inline]
 slab_pre_alloc_hook+0x42/0xc0 mm/slab.h:492
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3d/0x290 mm/slub.c:3233
 getname_flags+0xb5/0x500 fs/namei.c:138
 do_sys_openat2+0xcf/0x4a0 fs/open.c:1247
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6e4bb60407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffca80c2360 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f6e4ba72880 RCX: 00007f6e4bb60407
RDX: 0000000000080000 RSI: 00007ffca80c24e0 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055cb75d837f5
R13: 000055cb75d837f5 R14: 0000000000000001 R15: 00007ffca80c6b30
 </TASK>
RDX: 0000000000010000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ff7619
R10: fffffbfff1ff7619 R11: 1ffffffff1ff7618 R12: ffff88807cd03548
R13: dffffc0000000000 R14: ffffc90000dd0c08 R15: 0000000000000000
FS:  00007f6e4ba72880(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555583ba5808 CR3: 00000000185ba000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 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/0x458
 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+0x15b/0x2d0 kernel/trace/bpf_trace.c:1915
 trace_hrtimer_start include/trace/events/timer.h:199 [inline]
 debug_activate kernel/time/hrtimer.c:466 [inline]
 enqueue_hrtimer+0x314/0x370 kernel/time/hrtimer.c:1074
 __run_hrtimer kernel/time/hrtimer.c:1707 [inline]
 __hrtimer_run_queues+0x65a/0xc40 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:lock_is_held_type+0x13a/0x190 kernel/locking/lockdep.c:5671
Code: 75 40 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02 00 00 75 46 41 f7 c5 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
RSP: 0018:ffffc900012dfb98 EFLAGS: 00000206

RAX: d3b510027ebaa800 RBX: ffff88807cd01dc0 RCX: d3b510027ebaa800
RDX: 0000000000000000 RSI: ffffffff8a0b28c0 RDI: ffffffff8a59a240
RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad31be
R10: fffffbfff1ad31be R11: 1ffffffff1ad31bd R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff8c11c520 R15: 00000000ffffffff
 lock_is_held include/linux/lockdep.h:287 [inline]
 ___might_sleep+0xf2/0x600 kernel/sched/core.c:9624
 might_alloc include/linux/sched/mm.h:209 [inline]
 slab_pre_alloc_hook+0x42/0xc0 mm/slab.h:492
 slab_alloc_node mm/slub.c:3134 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 kmem_cache_alloc+0x3d/0x290 mm/slub.c:3233
 getname_flags+0xb5/0x500 fs/namei.c:138
 do_sys_openat2+0xcf/0x4a0 fs/open.c:1247
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f6e4bb60407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007ffca80c2360 EFLAGS: 00000202
 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f6e4ba72880 RCX: 00007f6e4bb60407
RDX: 0000000000080000 RSI: 00007ffca80c24e0 RDI: ffffffffffffff9c
RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 000055cb75d837f5
R13: 000055cb75d837f5 R14: 0000000000000001 R15: 00007ffca80c6b30
 </TASK>
----------------
Code disassembly (best guess):
   0:	75 40                	jne    0x42
   2:	48 c7 04 24 00 00 00 	movq   $0x0,(%rsp)
   9:	00
   a:	9c                   	pushf
   b:	8f 04 24             	pop    (%rsp)
   e:	f7 04 24 00 02 00 00 	testl  $0x200,(%rsp)
  15:	75 46                	jne    0x5d
  17:	41 f7 c5 00 02 00 00 	test   $0x200,%r13d
  1e:	74 01                	je     0x21
  20:	fb                   	sti
  21:	65 48 8b 04 25 28 00 	mov    %gs:0x28,%rax
  28:	00 00
* 2a:	48 3b 44 24 08       	cmp    0x8(%rsp),%rax <-- trapping instruction
  2f:	75 3c                	jne    0x6d
  31:	89 e8                	mov    %ebp,%eax
  33:	48 83 c4 10          	add    $0x10,%rsp
  37:	5b                   	pop    %rbx
  38:	41 5c                	pop    %r12
  3a:	41 5d                	pop    %r13
  3c:	41 5e                	pop    %r14
  3e:	41 5f                	pop    %r15

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/09/05 20:24 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in hrtimer_start_range_ns
2025/09/06 10:32 linux-5.15.y 7a6c2d093c45 d291dd2d .config console log report syz / log [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan-perf WARNING in hrtimer_start_range_ns
* Struck through repros no longer work on HEAD.