syzbot
WARNING in mmc_free_host
Status:
upstream: reported on 2026/08/19 18:13
Subsystems:
mmc
Labels:
prio:high
[Documentation on labels]
Reported-by: syzbot+82a0a7de6d84867d030e@syzkaller.appspotmail.com
First crash: 17d, last: 42m
Sample crash report:
------------[ cut here ]------------
do not call blocking ops when !TASK_RUNNING; state=2001 set at [<ffffffff8be67aae>] do_nanosleep+0x7e/0x6a0 kernel/time/hrtimer.c:-1
WARNING: kernel/sched/core.c:9161 at __might_sleep+0x92/0xf0 kernel/sched/core.c:9157, CPU#0: syz-executor/12294
Modules linked in:
CPU: 0 UID: 0 PID: 12294 Comm: syz-executor Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:__might_sleep+0xac/0xf0 kernel/sched/core.c:9157
Code: 00 00 48 89 3c 24 41 89 f5 4c 8d 35 5e 93 e6 0e 43 80 3c 3c 00 74 08 48 89 df e8 7f 06 a1 00 48 8b 0b 4c 89 f7 89 ee 48 89 ca <67> 48 0f b9 3a 44 89 ee 48 8b 3c 24 eb b5 44 89 f1 80 e1 07 80 c1
RSP: 0018:ffffc90000007c08 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88804ce2d728 RCX: ffffffff8be67aae
RDX: ffffffff8be67aae RSI: 0000000000002001 RDI: ffffffff907d1160
RBP: 0000000000002001 R08: 0000000000000100 R09: 1ffffffff20f426f
R10: dffffc0000000000 R11: fffffbfff20f4270 R12: 1ffff110099c5ae5
R13: 00000000000011d1 R14: ffffffff907d1160 R15: dffffc0000000000
FS: 000055558f02b500(0000) GS:ffff888124cda000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c40204a CR3: 0000000045a80000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000001 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
__cancel_work_sync+0x6d/0x110 kernel/workqueue.c:4561
mmc_free_host+0x19/0x30 drivers/mmc/core/host.c:700
call_timer_fn+0x18d/0x5f0 kernel/time/timer.c:1748
expire_timers kernel/time/timer.c:1799 [inline]
__run_timers kernel/time/timer.c:2374 [inline]
__run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386
run_timer_base kernel/time/timer.c:2395 [inline]
run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405
handle_softirqs+0x226/0x860 kernel/softirq.c:645
__do_softirq kernel/softirq.c:679 [inline]
invoke_softirq kernel/softirq.c:519 [inline]
__irq_exit_rcu+0xcb/0x220 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+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1062
</IRQ>
<TASK>
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+0x47/0x80 kernel/locking/spinlock.c:221
Code: f7 e8 5d 25 bd f5 f7 c3 00 02 00 00 74 05 e8 50 62 e9 f5 9c 58 a9 00 02 00 00 75 29 f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 <e8> f4 3e ae f5 65 48 8b 05 9c c1 ad 07 48 85 c0 74 18 5b 41 5e c3
RSP: 0018:ffffc9000444fb38 EFLAGS: 00000206
RAX: 0000000000000002 RBX: 0000000000000292 RCX: 8000000000000001
RDX: 0000000000000000 RSI: ffffffff8e474257 RDI: 0000000000000001
RBP: ffffffff9ac22078 R08: ffffffff907a137f R09: 1ffffffff20f426f
R10: dffffc0000000000 R11: fffffbfff20f4270 R12: ffff888057a516e0
R13: ffff888057a516c8 R14: ffffffff9ac22080 R15: dffffc0000000000
debug_object_assert_init+0x20d/0x380 lib/debugobjects.c:1072
debug_hrtimer_assert_init kernel/time/hrtimer.c:496 [inline]
hrtimer_start_range_ns_user+0x3d/0x430 kernel/time/hrtimer.c:1600
hrtimer_start_expires_user include/linux/hrtimer.h:247 [inline]
hrtimer_sleeper_start_expires kernel/time/hrtimer.c:2349 [inline]
do_nanosleep+0x16c/0x6a0 kernel/time/hrtimer.c:2426
hrtimer_nanosleep+0x18f/0x3a0 kernel/time/hrtimer.c:2475
__do_sys_clock_nanosleep kernel/time/posix-timers.c:1406 [inline]
__se_sys_clock_nanosleep+0x35b/0x3b0 kernel/time/posix-timers.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f64bbd5e98e
Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 <c3> 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08
RSP: 002b:00007f64bc14fd28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6
RAX: ffffffffffffffda RBX: 000055558f02b500 RCX: 00007f64bbd5e98e
RDX: 00007f64bc14fd80 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f64bc14fdec R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388
R13: 00000000000927c0 R14: 0000000000253621 R15: 00007f64bc14fe40
</TASK>
----------------
Code disassembly (best guess):
0: 00 00 add %al,(%rax)
2: 48 89 3c 24 mov %rdi,(%rsp)
6: 41 89 f5 mov %esi,%r13d
9: 4c 8d 35 5e 93 e6 0e lea 0xee6935e(%rip),%r14 # 0xee6936e
10: 43 80 3c 3c 00 cmpb $0x0,(%r12,%r15,1)
15: 74 08 je 0x1f
17: 48 89 df mov %rbx,%rdi
1a: e8 7f 06 a1 00 call 0xa1069e
1f: 48 8b 0b mov (%rbx),%rcx
22: 4c 89 f7 mov %r14,%rdi
25: 89 ee mov %ebp,%esi
27: 48 89 ca mov %rcx,%rdx
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 44 89 ee mov %r13d,%esi
32: 48 8b 3c 24 mov (%rsp),%rdi
36: eb b5 jmp 0xffffffed
38: 44 89 f1 mov %r14d,%ecx
3b: 80 e1 07 and $0x7,%cl
3e: 80 .byte 0x80
3f: c1 .byte 0xc1
* Struck through repros no longer work on HEAD.