INFO: task kworker/u4:11:3492 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:11 state:D stack:21512 pid:3492 ppid:2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6832
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b7/0xcc0 kernel/locking/mutex.c:747
jfs_commit_inode+0x1cb/0x520 fs/jfs/inode.c:108
jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138
write_inode fs/fs-writeback.c:1483 [inline]
__writeback_single_inode+0x705/0xee0 fs/fs-writeback.c:1700
writeback_sb_inodes+0x77c/0xef0 fs/fs-writeback.c:1926
__writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:1997
wb_writeback+0x464/0xba0 fs/fs-writeback.c:2107
wb_check_background_flush fs/fs-writeback.c:2177 [inline]
wb_do_writeback fs/fs-writeback.c:2265 [inline]
wb_workfn+0xb32/0xe20 fs/fs-writeback.c:2292
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
INFO: task syz.3.1111:11776 blocked for more than 144 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1111 state:D stack:27760 pid:11776 ppid:11022 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5380 [inline]
__schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
schedule+0xbd/0x170 kernel/sched/core.c:6773
io_schedule+0x80/0xd0 kernel/sched/core.c:9022
__lock_metapage fs/jfs/jfs_metapage.c:50 [inline]
lock_metapage+0x1ec/0x310 fs/jfs/jfs_metapage.c:64
__get_metapage+0x4ca/0xfa0 fs/jfs/jfs_metapage.c:639
ea_write+0x5e3/0xdd0 fs/jfs/xattr.c:256
ea_put fs/jfs/xattr.c:626 [inline]
__jfs_setxattr+0x931/0x1150 fs/jfs/xattr.c:792
__jfs_set_acl+0x121/0x1b0 fs/jfs/acl.c:87
jfs_set_acl+0x1d7/0x320 fs/jfs/acl.c:115
set_posix_acl fs/posix_acl.c:956 [inline]
vfs_set_acl+0x803/0xa60 fs/posix_acl.c:1135
do_set_acl+0xf5/0x180 fs/posix_acl.c:1280
do_setxattr fs/xattr.c:627 [inline]
__do_sys_fsetxattr fs/xattr.c:711 [inline]
__se_sys_fsetxattr+0x450/0x4b0 fs/xattr.c:687
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f487418f749
RSP: 002b:00007f48723f6038 EFLAGS: 00000246 ORIG_RAX: 00000000000000be
RAX: ffffffffffffffda RBX: 00007f48743e6180 RCX: 00007f487418f749
RDX: 00002000000001c0 RSI: 0000200000000280 RDI: 000000000000000a
RBP: 00007f4874213f91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000002c R11: 0000000000000246 R12: 0000000000000000
R13: 00007f48743e6218 R14: 00007f48743e6180 R15: 00007ffd84708ef8
Showing all locks held in the system:
1 lock held by khungtaskd/29:
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:334 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:786 [inline]
#0: ffffffff8cd2ff20 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x290 kernel/locking/lockdep.c:6633
4 locks held by kworker/u4:11/3492:
#0: ffff88801a27a138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88801a27a138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc9000cde7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000cde7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff8881627ae0e0 (&type->s_umount_key#63){++++}-{3:3}, at: super_trylock_shared+0x20/0xf0 fs/super.c:607
#3: ffff8881495ba6c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x1cb/0x520 fs/jfs/inode.c:108
2 locks held by getty/5529:
#0: ffff8880317c20a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000328b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x425/0x1380 drivers/tty/n_tty.c:2217
6 locks held by kworker/1:14/11421:
#0: ffff88814826e538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#0: ffff88814826e538 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#1: ffffc9000511fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:2609 [inline]
#1: ffffc9000511fd00 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x957/0x15b0 kernel/workqueue.c:2711
#2: ffff888142f61190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:995 [inline]
#2: ffff888142f61190 (&dev->mutex){....}-{3:3}, at: hub_event+0x185/0x49c0 drivers/usb/core/hub.c:5861
#3: ffff888025189508 (&port_dev->status_lock){+.+.}-{3:3}, at: usb_lock_port drivers/usb/core/hub.c:3215 [inline]
#3: ffff888025189508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5426 [inline]
#3: ffff888025189508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
#3: ffff888025189508 (&port_dev->status_lock){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5833 [inline]
#3: ffff888025189508 (&port_dev->status_lock){+.+.}-{3:3}, at: hub_event+0x21ab/0x49c0 drivers/usb/core/hub.c:5915
#4: ffff888141f8d368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect drivers/usb/core/hub.c:5427 [inline]
#4: ffff888141f8d368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_port_connect_change drivers/usb/core/hub.c:5669 [inline]
#4: ffff888141f8d368 (hcd->address0_mutex){+.+.}-{3:3}, at: port_event drivers/usb/core/hub.c:5833 [inline]
#4: ffff888141f8d368 (hcd->address0_mutex){+.+.}-{3:3}, at: hub_event+0x21d3/0x49c0 drivers/usb/core/hub.c:5915
#5: ffffffff8d8bf0f0 (ehci_cf_port_reset_rwsem){.+.+}-{3:3}, at: hub_port_reset+0x164/0x1740 drivers/usb/core/hub.c:3030
4 locks held by syz.3.1111/11776:
#0: ffff8881627ae418 (sb_writers#15){.+.+}-{0:0}, at: mnt_want_write_file+0x63/0x200 fs/namespace.c:456
#1: ffff8881495baa90 (&type->i_mutex_dir_key#12){++++}-{3:3}, at: inode_lock include/linux/fs.h:804 [inline]
#1: ffff8881495baa90 (&type->i_mutex_dir_key#12){++++}-{3:3}, at: vfs_set_acl+0x37a/0xa60 fs/posix_acl.c:1116
#2: ffff8881495ba6c8 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_set_acl+0x10a/0x320 fs/jfs/acl.c:107
#3: ffff8881495ba760 (&jfs_ip->xattr_sem){++++}-{3:3}, at: __jfs_setxattr+0xe2/0x1150 fs/jfs/xattr.c:678
7 locks held by dhcpcd-run-hook/14194:
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
nmi_cpu_backtrace+0x39b/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x2f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
watchdog+0xf41/0xf80 kernel/hung_task.c:379
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:get_current arch/x86/include/asm/current.h:41 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x8/0x60 kernel/kcov.c:215
Code: 00 00 f3 0f 1e fa 53 48 89 fb e8 13 00 00 00 48 8b 3d 9c 92 c4 0c 48 89 de 5b e9 43 9d 56 00 cc cc cc f3 0f 1e fa 48 8b 04 24 <65> 48 8b 0d f0 24 7e 7e 65 8b 15 f1 24 7e 7e 81 e2 00 01 ff 00 74
RSP: 0018:ffffc90000107518 EFLAGS: 00000293
RAX: ffffffff813ad979 RBX: ffffc900001076f8 RCX: ffff88801ba43c00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffffc900001076f8
RBP: ffffc900001076b8 R08: ffff88801ba43c00 R09: 0000000000000003
R10: 0000000000000004 R11: 0000000000000000 R12: ffffc90000107668
R13: dffffc0000000000 R14: ffffc900001076f8 R15: ffffffff8ecb89a4
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055f02374a008 CR3: 000000000cb30000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000001 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
__read_once_word_nocheck+0x9/0x10 include/asm-generic/rwonce.h:66
deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline]
unwind_next_frame+0x15f9/0x2970 arch/x86/kernel/unwind_orc.c:585
__unwind_start+0x66a/0x7e0 arch/x86/kernel/unwind_orc.c:760
unwind_start arch/x86/include/asm/unwind.h:64 [inline]
arch_stack_walk+0xf8/0x190 arch/x86/kernel/stacktrace.c:24
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:45 [inline]
kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1811 [inline]
slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837
slab_free mm/slub.c:3830 [inline]
kmem_cache_free+0xf8/0x280 mm/slub.c:3852
nsim_dev_trap_report drivers/net/netdevsim/dev.c:821 [inline]
nsim_dev_trap_report_work+0x76f/0xb00 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:2634 [inline]
process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
kthread+0x2fa/0x390 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293