syzbot
inconsistent lock state in mmc_free_host
Status:
upstream: reported C repro on 2026/08/28 22:24
Reported-by: syzbot+52f433058a3d152f1751@syzkaller.appspotmail.com
First crash: 2d06h, last: 8h16m
Sample crash report:
================================
WARNING: inconsistent lock state
syzkaller #0 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
syz-execprog/4193 [HC0[0]:SC1[1]:HE1:SE0] takes:
ffff88807b068710 ((work_completion)(&(&host->detect)->work)){+.?.}-{0:0}, at: __flush_work+0xfa/0x210 kernel/workqueue.c:3090
{SOFTIRQ-ON-W} state was registered at:
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__flush_work+0x116/0x210 kernel/workqueue.c:3090
__cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3181
__mmc_stop_host drivers/mmc/core/core.c:2294 [inline]
mmc_stop_host+0xd5/0x460 drivers/mmc/core/core.c:2299
mmc_remove_host+0x11/0x60 drivers/mmc/core/host.c:642
vub300_disconnect+0x14b/0x2e0 drivers/mmc/host/vub300.c:2388
usb_unbind_interface+0x203/0x870 drivers/usb/core/driver.c:458
__device_release_driver drivers/base/dd.c:1249 [inline]
device_release_driver_internal+0x487/0x710 drivers/base/dd.c:1282
bus_remove_device+0x2dd/0x400 drivers/base/bus.c:531
device_del+0x63f/0xa80 drivers/base/core.c:3615
usb_disable_device+0x3e7/0x8a0 drivers/usb/core/message.c:1472
usb_disconnect+0x33c/0x8a0 drivers/usb/core/hub.c:2287
hub_port_connect drivers/usb/core/hub.c:5341 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5637 [inline]
port_event drivers/usb/core/hub.c:5799 [inline]
hub_event+0x1d64/0x5260 drivers/usb/core/hub.c:5881
process_one_work+0x867/0xff0 kernel/workqueue.c:2310
process_scheduled_works kernel/workqueue.c:2373 [inline]
worker_thread+0xd93/0x12a0 kernel/workqueue.c:2459
kthread+0x42e/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
irq event stamp: 405220
hardirqs last enabled at (405220): [<ffffffff814e2b9a>] __cancel_work_timer+0x36a/0x560 kernel/workqueue.c:3174
hardirqs last disabled at (405219): [<ffffffff814dfe4b>] try_to_grab_pending+0xfb/0x820 kernel/workqueue.c:1272
softirqs last enabled at (399898): [<ffffffff814943fb>] __do_softirq kernel/softirq.c:610 [inline]
softirqs last enabled at (399898): [<ffffffff814943fb>] invoke_softirq kernel/softirq.c:450 [inline]
softirqs last enabled at (399898): [<ffffffff814943fb>] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
softirqs last disabled at (405155): [<ffffffff814943fb>] __do_softirq kernel/softirq.c:610 [inline]
softirqs last disabled at (405155): [<ffffffff814943fb>] invoke_softirq kernel/softirq.c:450 [inline]
softirqs last disabled at (405155): [<ffffffff814943fb>] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock((work_completion)(&(&host->detect)->work));
<Interrupt>
lock((work_completion)(&(&host->detect)->work));
*** DEADLOCK ***
1 lock held by syz-execprog/4193:
#0: ffffc90000007bc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline]
#0: ffffc90000007bc0 ((&vub300->inactivity_timer)){+.-.}-{0:0}, at: call_timer_fn+0xca/0x540 kernel/time/timer.c:1638
stack backtrace:
CPU: 0 PID: 4193 Comm: syz-execprog Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
valid_state+0x13b/0x1d0 kernel/locking/lockdep.c:3932
mark_lock_irq+0xa9/0x900 kernel/locking/lockdep.c:4135
mark_lock+0x208/0x320 kernel/locking/lockdep.c:4591
mark_usage kernel/locking/lockdep.c:-1 [inline]
__lock_acquire+0xc63/0x7b50 kernel/locking/lockdep.c:4966
lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
__flush_work+0x116/0x210 kernel/workqueue.c:3090
__cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3181
mmc_free_host+0x15/0x30 drivers/mmc/core/host.c:663
call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
expire_timers kernel/time/timer.c:1699 [inline]
__run_timers+0x56c/0x810 kernel/time/timer.c:1970
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
handle_softirqs+0x336/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> ef 90 88 f7 65 8b 05 60 a8 38 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90002e4f660 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 4b8ec11099f66300
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: 0000000000000001
RBP: ffffc90002e4f6f0 R08: ffff888016de4053 R09: 1ffff11002dbc80a
R10: dffffc0000000000 R11: ffffed1002dbc80b R12: dffffc0000000000
R13: ffff888016de4050 R14: ffff888016de4050 R15: 1ffff920005c9ecc
spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1538 [inline]
release_pages+0x191/0x1bd0 mm/swap.c:903
tlb_batch_pages_flush mm/mmu_gather.c:50 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:241 [inline]
tlb_flush_mmu+0xce/0x180 mm/mmu_gather.c:248
zap_pte_range mm/memory.c:1456 [inline]
zap_pmd_range mm/memory.c:1505 [inline]
zap_pud_range mm/memory.c:1534 [inline]
zap_p4d_range mm/memory.c:1555 [inline]
unmap_page_range+0x1f7f/0x2410 mm/memory.c:1576
unmap_vmas+0x131/0x250 mm/memory.c:1653
exit_mmap+0x3b9/0x640 mm/mmap.c:3216
__mmput+0x115/0x390 kernel/fork.c:1133
exit_mm+0x632/0x7b0 kernel/exit.c:557
do_exit+0x5b8/0x2110 kernel/exit.c:877
do_group_exit+0x12c/0x2f0 kernel/exit.c:1004
__do_sys_exit_group kernel/exit.c:1015 [inline]
__se_sys_exit_group kernel/exit.c:1013 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1013
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: 0033:0x49374b
Code: Unable to access opcode bytes at RIP 0x493721.
RSP: 002b:00001970ed423f40 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000049374b
RDX: 00001970ed423f10 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 00001970ed423fd0 R08: 0000000000000007 R09: ffffffffffffffff
R10: 00007fdc29bc25f8 R11: 0000000000000202 R12: 0000000000000004
R13: 00001970f33540f0 R14: 00001970eb63e1e0 R15: ffffffffffffffff
</TASK>
BUG: sleeping function called from invalid context at kernel/workqueue.c:3031
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 4193, name: syz-execprog
INFO: lockdep is turned off.
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 0 PID: 4193 Comm: syz-execprog Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
<IRQ>
dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
___might_sleep+0x493/0x610 kernel/sched/core.c:9658
start_flush_work+0x2e/0x830 kernel/workqueue.c:3031
__flush_work+0x148/0x210 kernel/workqueue.c:3093
__cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3181
mmc_free_host+0x15/0x30 drivers/mmc/core/host.c:663
call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
expire_timers kernel/time/timer.c:1699 [inline]
__run_timers+0x56c/0x810 kernel/time/timer.c:1970
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
handle_softirqs+0x336/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> ef 90 88 f7 65 8b 05 60 a8 38 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90002e4f660 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 4b8ec11099f66300
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: 0000000000000001
RBP: ffffc90002e4f6f0 R08: ffff888016de4053 R09: 1ffff11002dbc80a
R10: dffffc0000000000 R11: ffffed1002dbc80b R12: dffffc0000000000
R13: ffff888016de4050 R14: ffff888016de4050 R15: 1ffff920005c9ecc
spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1538 [inline]
release_pages+0x191/0x1bd0 mm/swap.c:903
tlb_batch_pages_flush mm/mmu_gather.c:50 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:241 [inline]
tlb_flush_mmu+0xce/0x180 mm/mmu_gather.c:248
zap_pte_range mm/memory.c:1456 [inline]
zap_pmd_range mm/memory.c:1505 [inline]
zap_pud_range mm/memory.c:1534 [inline]
zap_p4d_range mm/memory.c:1555 [inline]
unmap_page_range+0x1f7f/0x2410 mm/memory.c:1576
unmap_vmas+0x131/0x250 mm/memory.c:1653
exit_mmap+0x3b9/0x640 mm/mmap.c:3216
__mmput+0x115/0x390 kernel/fork.c:1133
exit_mm+0x632/0x7b0 kernel/exit.c:557
do_exit+0x5b8/0x2110 kernel/exit.c:877
do_group_exit+0x12c/0x2f0 kernel/exit.c:1004
__do_sys_exit_group kernel/exit.c:1015 [inline]
__se_sys_exit_group kernel/exit.c:1013 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1013
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: 0033:0x49374b
Code: Unable to access opcode bytes at RIP 0x493721.
RSP: 002b:00001970ed423f40 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000049374b
RDX: 00001970ed423f10 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 00001970ed423fd0 R08: 0000000000000007 R09: ffffffffffffffff
R10: 00007fdc29bc25f8 R11: 0000000000000202 R12: 0000000000000004
R13: 00001970f33540f0 R14: 00001970eb63e1e0 R15: ffffffffffffffff
</TASK>
ODEBUG: object ffffc900000079a0 is NOT on stack ffffc90002e48000, but annotated.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 4193 at lib/debugobjects.c:561 debug_object_is_on_stack lib/debugobjects.c:-1 [inline]
WARNING: CPU: 0 PID: 4193 at lib/debugobjects.c:561 lookup_object_or_alloc lib/debugobjects.c:594 [inline]
WARNING: CPU: 0 PID: 4193 at lib/debugobjects.c:561 __debug_object_init+0x4c0/0xc80 lib/debugobjects.c:621
Modules linked in:
CPU: 0 PID: 4193 Comm: syz-execprog Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:561 [inline]
RIP: 0010:lookup_object_or_alloc lib/debugobjects.c:594 [inline]
RIP: 0010:__debug_object_init+0x4c0/0xc80 lib/debugobjects.c:621
Code: 06 12 73 12 48 c7 c1 c0 4b 7a 8a 48 c7 c7 20 4c 7a 8a 84 c0 48 0f 45 f9 4c 89 ee e8 1a cc c8 05 48 be 00 00 00 00 00 fc ff df <0f> 0b e9 4d fd ff ff 83 3d 32 11 73 12 00 4c 89 6c 24 28 0f 84 23
RSP: 0018:ffffc900000077e0 EFLAGS: 00010046
RAX: 0000000000000050 RBX: 0000000000000001 RCX: 4b8ec11099f66300
RDX: 0000000000000100 RSI: dffffc0000000000 RDI: 0000000000000000
RBP: ffffc90000007950 R08: ffffc90000007307 R09: 1ffff92000000e60
R10: dffffc0000000000 R11: fffff52000000e61 R12: f8f8f8f8f8f8f8f8
R13: ffffc900000079a0 R14: ffff88801d75bba0 R15: ffff88807f7a0690
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055d5566d5030 CR3: 000000002aa97000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__synchronize_srcu+0x229/0x350 kernel/rcu/srcutree.c:928
wakeup_source_remove drivers/base/power/wakeup.c:203 [inline]
wakeup_source_unregister+0x112/0x190 drivers/base/power/wakeup.c:247
mmc_host_classdev_release+0x43/0xf0 drivers/mmc/core/host.c:77
device_release+0x92/0x1c0 drivers/base/core.c:-1
kobject_cleanup lib/kobject.c:713 [inline]
kobject_release lib/kobject.c:744 [inline]
kref_put include/linux/kref.h:65 [inline]
kobject_put+0x217/0x450 lib/kobject.c:761
call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
expire_timers kernel/time/timer.c:1699 [inline]
__run_timers+0x56c/0x810 kernel/time/timer.c:1970
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
handle_softirqs+0x336/0x830 kernel/softirq.c:576
__do_softirq kernel/softirq.c:610 [inline]
invoke_softirq kernel/softirq.c:450 [inline]
__irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
sysvec_apic_timer_interrupt+0xa0/0xc0 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:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:161 [inline]
RIP: 0010:_raw_spin_unlock_irqrestore+0xbc/0x120 kernel/locking/spinlock.c:194
Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> ef 90 88 f7 65 8b 05 60 a8 38 76 85 c0 74 3c 48 c7 04 24 0e 36
RSP: 0018:ffffc90002e4f660 EFLAGS: 00000206
RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 4b8ec11099f66300
RDX: dffffc0000000000 RSI: ffffffff8a2b2be0 RDI: 0000000000000001
RBP: ffffc90002e4f6f0 R08: ffff888016de4053 R09: 1ffff11002dbc80a
R10: dffffc0000000000 R11: ffffed1002dbc80b R12: dffffc0000000000
R13: ffff888016de4050 R14: ffff888016de4050 R15: 1ffff920005c9ecc
spin_unlock_irqrestore include/linux/spinlock.h:419 [inline]
unlock_page_lruvec_irqrestore include/linux/memcontrol.h:1538 [inline]
release_pages+0x191/0x1bd0 mm/swap.c:903
tlb_batch_pages_flush mm/mmu_gather.c:50 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:241 [inline]
tlb_flush_mmu+0xce/0x180 mm/mmu_gather.c:248
zap_pte_range mm/memory.c:1456 [inline]
zap_pmd_range mm/memory.c:1505 [inline]
zap_pud_range mm/memory.c:1534 [inline]
zap_p4d_range mm/memory.c:1555 [inline]
unmap_page_range+0x1f7f/0x2410 mm/memory.c:1576
unmap_vmas+0x131/0x250 mm/memory.c:1653
exit_mmap+0x3b9/0x640 mm/mmap.c:3216
__mmput+0x115/0x390 kernel/fork.c:1133
exit_mm+0x632/0x7b0 kernel/exit.c:557
do_exit+0x5b8/0x2110 kernel/exit.c:877
do_group_exit+0x12c/0x2f0 kernel/exit.c:1004
__do_sys_exit_group kernel/exit.c:1015 [inline]
__se_sys_exit_group kernel/exit.c:1013 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1013
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: 0033:0x49374b
Code: Unable to access opcode bytes at RIP 0x493721.
RSP: 002b:00001970ed423f40 EFLAGS: 00000202 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000049374b
RDX: 00001970ed423f10 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 00001970ed423fd0 R08: 0000000000000007 R09: ffffffffffffffff
R10: 00007fdc29bc25f8 R11: 0000000000000202 R12: 0000000000000004
R13: 00001970f33540f0 R14: 00001970eb63e1e0 R15: ffffffffffffffff
</TASK>
----------------
Code disassembly (best guess):
0: c7 44 24 20 00 00 00 movl $0x0,0x20(%rsp)
7: 00
8: 9c pushf
9: 8f 44 24 20 pop 0x20(%rsp)
d: f7 44 24 20 00 02 00 testl $0x200,0x20(%rsp)
14: 00
15: 41 c6 04 07 f8 movb $0xf8,(%r15,%rax,1)
1a: 75 4b jne 0x67
1c: f7 c3 00 02 00 00 test $0x200,%ebx
22: 74 01 je 0x25
24: fb sti
25: bf 01 00 00 00 mov $0x1,%edi
* 2a: e8 ef 90 88 f7 call 0xf788911e <-- trapping instruction
2f: 65 8b 05 60 a8 38 76 mov %gs:0x7638a860(%rip),%eax # 0x7638a896
36: 85 c0 test %eax,%eax
38: 74 3c je 0x76
3a: 48 rex.W
3b: c7 .byte 0xc7
3c: 04 24 add $0x24,%al
3e: 0e (bad)
3f: 36 ss
Struck through repros no longer work on HEAD.