INFO: task kworker/u4:10:4906 blocked for more than 143 seconds.
Not tainted 5.15.180-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:10 state:D stack:19992 pid: 4906 ppid: 2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:7)
Call Trace:
context_switch kernel/sched/core.c:5030 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
schedule+0x11b/0x1f0 kernel/sched/core.c:6459
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6518
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102
jfs_write_inode+0x13f/0x210 fs/jfs/inode.c:132
write_inode fs/fs-writeback.c:1495 [inline]
__writeback_single_inode+0x644/0xe30 fs/fs-writeback.c:1705
writeback_sb_inodes+0xbce/0x1a40 fs/fs-writeback.c:1930
__writeback_inodes_wb+0x114/0x400 fs/fs-writeback.c:2001
wb_writeback+0x465/0xc50 fs/fs-writeback.c:2106
wb_check_background_flush fs/fs-writeback.c:2172 [inline]
wb_do_writeback fs/fs-writeback.c:2260 [inline]
wb_workfn+0xd07/0x1130 fs/fs-writeback.c:2288
process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Showing all locks held in the system:
1 lock held by khungtaskd/27:
#0: ffffffff8cb1f4e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
3 locks held by kworker/u4:3/1209:
2 locks held by getty/3927:
#0: ffff88802c9e5098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc900025c62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by kworker/u4:9/4901:
4 locks held by kworker/u4:10/4906:
#0: ffff888141dc0938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900031efd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffff88801f47a0e0 (&type->s_umount_key#84){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
#3: ffff8880615a3008 (&jfs_ip->commit_mutex){+.+.}-{3:3}, at: jfs_commit_inode+0x242/0x580 fs/jfs/inode.c:102
3 locks held by kworker/1:11/5158:
#0: ffff88802ba10938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003edfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8dc44008 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xd8/0x16f0 net/ipv6/addrconf.c:4113
4 locks held by syz.7.349/6257:
3 locks held by kworker/0:14/7973:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90002e6fd20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffff88807ef4d240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2cd/0x4120 drivers/net/netdevsim/fib.c:1480
1 lock held by syz-executor/8481:
#0: ffffffff8dc44008 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8dc44008 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x956/0xef0 net/core/rtnetlink.c:5647
2 locks held by syz.9.797/8718:
#0: ffffffff8dc44008 (rtnl_mutex){+.+.}-{3:3}, at: ppp_release+0x86/0x1f0 drivers/net/ppp/ppp_generic.c:416
#1: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#1: ffffffff8cb23aa8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:369
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3528 Comm: syslogd Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x60 kernel/kcov.c:202
Code: 1f 84 00 00 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d a8 65 8a 0c 48 89 de 5b e9 77 19 49 00 00 00 cc cc 00 00 cc <48> 8b 04 24 65 48 8b 0d 74 2d 82 7e 65 8b 15 75 2d 82 7e 81 e2 00
RSP: 0018:ffffc9000e067820 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88807ecc5940
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffea0001525c48 R08: ffffffff81ac4adc R09: fffff94000235e51
R10: 0000000000000000 R11: dffffc0000000001 R12: 00fff0000008003f
R13: dffffc0000000000 R14: ffffea00011af288 R15: ffffea00011af280
FS: 00007fce9c312380(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc0bda7b58 CR3: 000000002b900000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
_compound_head include/linux/page-flags.h:198 [inline]
PageReferenced include/linux/page-flags.h:345 [inline]
mark_page_accessed+0x104/0x1330 mm/swap.c:406
shmem_getpage_gfp+0x4bc/0x3190 mm/shmem.c:1866
shmem_getpage mm/shmem.c:151 [inline]
shmem_write_begin+0xce/0x1a0 mm/shmem.c:2474
generic_perform_write+0x2bf/0x5b0 mm/filemap.c:3785
__generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3912
generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3944
call_write_iter include/linux/fs.h:2172 [inline]
new_sync_write fs/read_write.c:507 [inline]
vfs_write+0xacd/0xe50 fs/read_write.c:594
ksys_write+0x1a2/0x2c0 fs/read_write.c:647
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x3b/0x80 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fce9c466bf2
Code: 89 c7 48 89 44 24 08 e8 7b 34 fa ff 48 8b 44 24 08 48 83 c4 28 c3 c3 64 8b 04 25 18 00 00 00 85 c0 75 20 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 76 6f 48 8b 15 07 a2 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffd922cb658 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007fce9c466bf2
RDX: 0000000000000070 RSI: 0000560bf4e2cc50 RDI: 0000000000000003
RBP: 0000560bf4e2cc50 R08: 0000000000000001 R09: 0000000000000000
R10: 00007fce9c6053a3 R11: 0000000000000246 R12: 0000000000000070
R13: 00007fce9c312300 R14: 0000000000000004 R15: 0000560bf4e2ca60