INFO: task syz-executor:6107 blocked for more than 149 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:18856 pid:6107 tgid:6107 ppid:6101 task_flags:0x400140 flags:0x00004000
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x1798/0x4cc0 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
wb_wait_for_completion+0x15f/0x260 fs/fs-writeback.c:216
__writeback_inodes_sb_nr+0x1f6/0x250 fs/fs-writeback.c:2748
sync_filesystem+0xa3/0x230 fs/sync.c:54
generic_shutdown_super+0x6f/0x2c0 fs/super.c:622
kill_block_super+0x44/0x90 fs/super.c:1766
exfat_kill_sb+0x41/0x80 fs/exfat/super.c:801
deactivate_locked_super+0xbc/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f370518ff17
RSP: 002b:00007ffcfe623f78 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3705211c05 RCX: 00007f370518ff17
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffcfe624030
RBP: 00007ffcfe624030 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffcfe6250c0
R13: 00007f3705211c05 R14: 000000000008d0b3 R15: 00007ffcfe625100
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 33 Comm: kworker/R-write Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Workqueue: writeback wb_workfn (flush-7:3)
RIP: 0010:memcg_slab_post_alloc_hook mm/slub.c:2213 [inline]
RIP: 0010:slab_post_alloc_hook mm/slub.c:4190 [inline]
RIP: 0010:slab_alloc_node mm/slub.c:4229 [inline]
RIP: 0010:__kmalloc_cache_noprof+0x1f5/0x3d0 mm/slub.c:4391
Code: c0 41 80 f6 01 41 08 c6 75 0d 44 89 e2 48 89 df 31 f6 e8 be 5f 61 09 66 90 f7 c5 00 00 40 00 0f 85 cc 00 00 00 41 f6 47 09 80 <0f> 85 c1 00 00 00 f3 0f 1e fa 41 8b 4f 18 48 8b 7c 24 08 48 89 de
RSP: 0018:ffffc900000076f0 EFLAGS: 00000046
RAX: ffff8881c237cf00 RBX: ffff8881c237cf00 RCX: 0000000000000000
RDX: 0000000000000080 RSI: 0000000000000000 RDI: ffff8881c237cf80
RBP: 0000000000000820 R08: ffff888020bf969b R09: ffff8881c237cf00
R10: dffffc0000000000 R11: ffffffff877ebee0 R12: 0000000000000080
R13: ffff8881c237cf00 R14: 0000000003e21f00 R15: ffff88801a441a00
FS: 0000000000000000(0000) GS:ffff888125c1b000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b31e16ff8 CR3: 00000000766c4000 CR4: 0000000000350ef0
Call Trace:
kmalloc_noprof include/linux/slab.h:905 [inline]
dummy_urb_enqueue+0x7c/0x780 drivers/usb/gadget/udc/dummy_hcd.c:1273
usb_hcd_submit_urb+0x325/0x1aa0 drivers/usb/core/hcd.c:1546
ath9k_hif_usb_reg_in_cb+0x4d5/0x6f0 drivers/net/wireless/ath/ath9k/hif_usb.c:790
__usb_hcd_giveback_urb+0x41a/0x690 drivers/usb/core/hcd.c:1663
dummy_timer+0x862/0x4550 drivers/usb/gadget/udc/dummy_hcd.c:1995
__run_hrtimer kernel/time/hrtimer.c:1761 [inline]
__hrtimer_run_queues+0x52c/0xc60 kernel/time/hrtimer.c:1825
hrtimer_run_softirq+0x187/0x2b0 kernel/time/hrtimer.c:1842
handle_softirqs+0x286/0x870 kernel/softirq.c:579
__do_softirq kernel/softirq.c:613 [inline]
invoke_softirq kernel/softirq.c:453 [inline]
__irq_exit_rcu+0xca/0x1f0 kernel/softirq.c:680
irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:_raw_spin_lock+0x5/0x40 kernel/locking/spinlock.c:153
Code: e8 90 dc 08 f6 31 ed 89 e8 5b 41 5e 5d e9 be 36 94 f5 cc 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 53 <48> 89 fb bf 01 00 00 00 e8 3e f1 13 f6 48 8d 7b 18 31 f6 31 d2 31
RSP: 0018:ffffc90000a976d0 EFLAGS: 00000246
RAX: 1ffff92000152ef3 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: 0000000000000028 RSI: 0000000000000000 RDI: ffff888024bb40c0
RBP: ffffc90000a97810 R08: ffffc90000a97787 R09: ffffc90000a97760
R10: dffffc0000000000 R11: fffff52000152ef1 R12: 1ffff92000152edc
R13: ffff888140a80618 R14: ffff888024bb4068 R15: ffff888024bb40c0
spin_lock include/linux/spinlock.h:351 [inline]
writeback_inodes_wb+0xf3/0x1e0 fs/fs-writeback.c:2074
wb_workfn+0xeb0/0xef0 fs/fs-writeback.c:2352
process_one_work kernel/workqueue.c:3236 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3319
rescuer_thread+0x53c/0xdd0 kernel/workqueue.c:3496
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245