BUG: sleeping function called from invalid context at kernel/workqueue.c:4561 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 16, name: pr/ttyS0 preempt_count: 101, expected: 0 RCU nest depth: 0, expected: 0 locks held by pr/ttyS0/16: 2, last CPU#0: #0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: rcu_try_lock_acquire include/linux/rcupdate.h:314 [inline] #0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: srcu_read_lock_nmisafe include/linux/srcu.h:439 [inline] #0: ffffffff8edd87b8 (console_srcu){....}-{0:0}, at: console_srcu_read_lock+0x49/0x60 kernel/printk/printk.c:291 #1: ffffc90000007c98 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11d/0x5f0 kernel/time/timer.c:1745 Preemption disabled at: [<0000000000000000>] 0x0 CPU: 0 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 __might_resched.cold+0x1dc/0x222 kernel/sched/core.c:9257 __cancel_work_sync kernel/workqueue.c:4561 [inline] cancel_delayed_work_sync+0xb8/0xf0 kernel/workqueue.c:4642 mmc_free_host+0x19/0x40 drivers/mmc/core/host.c:700 vub300_delete drivers/mmc/host/vub300.c:379 [inline] kref_put include/linux/kref.h:65 [inline] vub300_inactivity_timer_expired drivers/mmc/host/vub300.c:747 [inline] vub300_inactivity_timer_expired+0x42f/0x550 drivers/mmc/host/vub300.c:742 call_timer_fn+0x198/0x5f0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x757/0xb00 kernel/time/timer.c:2374 __run_timer_base kernel/time/timer.c:2386 [inline] __run_timer_base kernel/time/timer.c:2378 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2395 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:221 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 09 13 f6 48 89 df e8 3e 60 13 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 95 56 02 f6 65 48 83 3d 74 54 b8 08 00 74 16 5b RSP: 0018:ffffc90000157ca8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff9bc6ee60 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff8e38c98a RDI: ffffffff8c623580 RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 205d363137355420 R12: 1ffff9200002af98 R13: ffffffff8fbd85c0 R14: 0000000000000001 R15: 0000000000000000 nbcon_emit_one+0x15c/0x2b0 kernel/printk/nbcon.c:1165 nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ODEBUG: object ffffc90000007a60 is NOT on stack ffffc90000150000, but annotated. ------------[ cut here ]------------ 1 WARNING: lib/debugobjects.c:672 at debug_object_is_on_stack lib/debugobjects.c:672 [inline], CPU#0: pr/ttyS0/16 WARNING: lib/debugobjects.c:672 at lookup_object_or_alloc.part.0.cold+0x19/0x40 lib/debugobjects.c:705, CPU#0: pr/ttyS0/16 Modules linked in: CPU: 0 UID: 0 PID: 16 Comm: pr/ttyS0 Tainted: G W L syzkaller #0 PREEMPT(full) Tainted: [W]=WARN, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2026 RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:672 [inline] RIP: 0010:lookup_object_or_alloc.part.0.cold+0x19/0x40 lib/debugobjects.c:705 Code: c4 60 5b 5d 41 5c 41 5d 41 5e 41 5f e9 19 fc 9d 0a 83 c5 01 89 2d 10 32 7d 1a 4c 89 e6 48 c7 c7 c0 40 62 8c e8 91 ae eb ff 90 <0f> 0b 90 e9 92 59 fe 03 83 c5 01 89 2d ef 31 7d 1a 49 39 c4 73 da RSP: 0018:ffffc900000078f0 EFLAGS: 00010082 RAX: 0000000000000050 RBX: ffff8880520db850 RCX: 0000000000000000 RDX: 0000000000000050 RSI: ffffffff81ea1339 RDI: fffff52000000f0f RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: 8000000000000102 R11: 0000000000000001 R12: ffffc90000007a60 R13: ffff88801f298000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888123b56000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd8d28d2851 CR3: 000000007c957000 CR4: 00000000003526f0 Call Trace: lookup_object_or_alloc lib/debugobjects.c:682 [inline] __debug_object_init+0x2a9/0x3d0 lib/debugobjects.c:798 __synchronize_srcu+0x1c3/0x300 kernel/rcu/srcutree.c:1475 wakeup_source_remove drivers/base/power/wakeup.c:201 [inline] wakeup_source_unregister.part.0+0x12c/0x540 drivers/base/power/wakeup.c:237 wakeup_source_unregister+0x1f/0x30 drivers/base/power/wakeup.c:236 mmc_host_classdev_release+0x42/0x120 drivers/mmc/core/host.c:69 device_release+0xd2/0x270 drivers/base/core.c:2640 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1f7/0x640 lib/kobject.c:737 put_device+0x1f/0x30 drivers/base/core.c:3884 vub300_delete drivers/mmc/host/vub300.c:379 [inline] kref_put include/linux/kref.h:65 [inline] vub300_inactivity_timer_expired drivers/mmc/host/vub300.c:747 [inline] vub300_inactivity_timer_expired+0x42f/0x550 drivers/mmc/host/vub300.c:742 call_timer_fn+0x198/0x5f0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers+0x757/0xb00 kernel/time/timer.c:2374 __run_timer_base kernel/time/timer.c:2386 [inline] __run_timer_base kernel/time/timer.c:2378 [inline] run_timer_base+0x114/0x190 kernel/time/timer.c:2395 run_timer_softirq+0x1a/0x50 kernel/time/timer.c:2405 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:211 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x31/0x80 kernel/locking/spinlock.c:221 Code: f5 53 48 8b 74 24 10 48 89 fb 48 83 c7 18 e8 b6 09 13 f6 48 89 df e8 3e 60 13 f6 f7 c5 00 02 00 00 75 23 9c 58 f6 c4 02 75 37 01 00 00 00 e8 95 56 02 f6 65 48 83 3d 74 54 b8 08 00 74 16 5b RSP: 0018:ffffc90000157ca8 EFLAGS: 00000246 RAX: 0000000000000002 RBX: ffffffff9bc6ee60 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffffffff8e38c98a RDI: ffffffff8c623580 RBP: 0000000000000246 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 205d363137355420 R12: 1ffff9200002af98 R13: ffffffff8fbd85c0 R14: 0000000000000001 R15: 0000000000000000 nbcon_emit_one+0x15c/0x2b0 kernel/printk/nbcon.c:1165 nbcon_kthread_func+0x613/0x7d0 kernel/printk/nbcon.c:1271 kthread+0x373/0x450 kernel/kthread.c:436 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: f5 cmc 1: 53 push %rbx 2: 48 8b 74 24 10 mov 0x10(%rsp),%rsi 7: 48 89 fb mov %rdi,%rbx a: 48 83 c7 18 add $0x18,%rdi e: e8 b6 09 13 f6 call 0xf61309c9 13: 48 89 df mov %rbx,%rdi 16: e8 3e 60 13 f6 call 0xf6136059 1b: f7 c5 00 02 00 00 test $0x200,%ebp 21: 75 23 jne 0x46 23: 9c pushf 24: 58 pop %rax 25: f6 c4 02 test $0x2,%ah 28: 75 37 jne 0x61 * 2a: bf 01 00 00 00 mov $0x1,%edi <-- trapping instruction 2f: e8 95 56 02 f6 call 0xf60256c9 34: 65 48 83 3d 74 54 b8 cmpq $0x0,%gs:0x8b85474(%rip) # 0x8b854b1 3b: 08 00 3d: 74 16 je 0x55 3f: 5b pop %rbx