BUG: sleeping function called from invalid context at kernel/workqueue.c:4552 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 0, name: swapper/0 preempt_count: 101, expected: 0 RCU nest depth: 0, expected: 0 locks held by swapper/0/0: 1, last CPU#0: #0: ffffc90000007c98 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0x11d/0x5f0 kernel/time/timer.c:1745 Preemption disabled at: [] schedule_preempt_disabled+0x1d/0x30 kernel/sched/core.c:7420 CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(lazy) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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:9234 __cancel_work_sync kernel/workqueue.c:4552 [inline] cancel_delayed_work_sync+0xb8/0xf0 kernel/workqueue.c:4633 mmc_free_host+0x19/0x30 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+0x1d9/0x9b0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0x192/0x210 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 20 c4 01 e9 03 f9 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 80 1f 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff89607d00 EFLAGS: 00000246 RAX: 0000000000acad87 RBX: ffffffff8962c940 RCX: ffffffff878708d5 RDX: 0000000000000001 RSI: ffffffff89326361 RDI: ffffffff87d29880 RBP: fffffbfff12c5928 R08: 0000000000000001 R09: ffffed103eac673d R10: ffff8881f56339eb R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffffffff12c0fa4 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3ae/0x5b0 kernel/sched/idle.c:355 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454 rest_init+0x2d3/0x2e0 init/main.c:727 start_kernel+0x489/0x490 init/main.c:1185 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x158 ODEBUG: object ffffc90000007a60 is NOT on stack ffffffff89600000, but annotated. ------------[ cut here ]------------ 1 WARNING: lib/debugobjects.c:672 at debug_object_is_on_stack lib/debugobjects.c:672 [inline], CPU#0: swapper/0/0 WARNING: lib/debugobjects.c:672 at lookup_object_or_alloc.part.0.cold+0x19/0x40 lib/debugobjects.c:705, CPU#0: swapper/0/0 Modules linked in: CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Tainted: G W syzkaller #0 PREEMPT(lazy) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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: 48 83 c4 60 5b 5d 41 5c 41 5d 41 5e c3 cc cc cc cc 83 c5 01 89 2d 2a 30 0e 13 4c 89 e6 48 c7 c7 c0 a3 d2 87 e8 4b c7 fa ff 90 <0f> 0b 90 e9 cc 94 ba 01 83 c5 01 89 2d 09 30 0e 13 49 39 c4 73 da RSP: 0018:ffffc900000078f0 EFLAGS: 00010082 RAX: 0000000000000050 RBX: ffff888116184380 RCX: 0000000000000000 RDX: 0000000000000050 RSI: ffffffff81936299 RDI: fffff52000000f0f RBP: 0000000000000001 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000102 R11: 0000000000000001 R12: ffffc90000007a60 R13: ffffffff8962c940 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8882683eb000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fafc0e64fd0 CR3: 000000012fa2c000 CR4: 00000000003506f0 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+0x1d9/0x9b0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] invoke_softirq kernel/softirq.c:519 [inline] __irq_exit_rcu+0x192/0x210 kernel/softirq.c:767 irq_exit_rcu+0x9/0x30 kernel/softirq.c:784 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1062 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:64 Code: 20 c4 01 e9 03 f9 02 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d e3 80 1f 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffffff89607d00 EFLAGS: 00000246 RAX: 0000000000acad87 RBX: ffffffff8962c940 RCX: ffffffff878708d5 RDX: 0000000000000001 RSI: ffffffff89326361 RDI: ffffffff87d29880 RBP: fffffbfff12c5928 R08: 0000000000000001 R09: ffffed103eac673d R10: ffff8881f56339eb R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 1ffffffff12c0fa4 R15: dffffc0000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:768 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x3ae/0x5b0 kernel/sched/idle.c:355 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454 rest_init+0x2d3/0x2e0 init/main.c:727 start_kernel+0x489/0x490 init/main.c:1185 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291 common_startup_64+0x13e/0x158 ---------------- Code disassembly (best guess): 0: 20 c4 and %al,%ah 2: 01 e9 add %ebp,%ecx 4: 03 f9 add %ecx,%edi 6: 02 00 add (%rax),%al 8: 0f 1f 00 nopl (%rax) 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: 90 nop 1a: 90 nop 1b: f3 0f 1e fa endbr64 1f: 66 90 xchg %ax,%ax 21: 0f 00 2d e3 80 1f 00 verw 0x1f80e3(%rip) # 0x1f810b 28: fb sti 29: f4 hlt * 2a: c3 ret <-- trapping instruction 2b: cc int3 2c: cc int3 2d: cc int3 2e: cc int3 2f: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1) 36: 00 00 00 39: 66 90 xchg %ax,%ax 3b: 90 nop 3c: 90 nop 3d: 90 nop 3e: 90 nop 3f: 90 nop