INFO: task kworker/u8:6:1336 blocked for more than 143 seconds.
Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:6 state:D stack:20904 pid:1336 tgid:1336 ppid:2 task_flags:0x4208060 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:3)
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
__mutex_lock_common kernel/locking/mutex.c:678 [inline]
__mutex_lock+0x805/0x10c0 kernel/locking/mutex.c:746
jfs_commit_inode+0x2a6/0x600 fs/jfs/inode.c:102
jfs_write_inode+0x143/0x220 fs/jfs/inode.c:132
write_inode fs/fs-writeback.c:1525 [inline]
__writeback_single_inode+0x708/0x10d0 fs/fs-writeback.c:1745
writeback_sb_inodes+0x822/0x1360 fs/fs-writeback.c:1976
__writeback_inodes_wb+0x11b/0x260 fs/fs-writeback.c:2047
wb_writeback+0x429/0xb90 fs/fs-writeback.c:2158
wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
wb_do_writeback fs/fs-writeback.c:2315 [inline]
wb_workfn+0xbbc/0x10b0 fs/fs-writeback.c:2343
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xac3/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd50 kernel/workqueue.c:3400
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
INFO: task syz.4.105:6626 blocked for more than 144 seconds.
Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.105 state:D stack:23688 pid:6626 tgid:6624 ppid:5827 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x1b33/0x51f0 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x163/0x360 kernel/sched/core.c:6860
wb_wait_for_completion+0x166/0x270 fs/fs-writeback.c:216
sync_inodes_sb+0x28f/0xb50 fs/fs-writeback.c:2833
iterate_supers+0xc6/0x190 fs/super.c:934
ksys_sync+0xc2/0x1d0 fs/sync.c:102
__do_sys_sync+0xe/0x20 fs/sync.c:113
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf3/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb07af8e169
RSP: 002b:00007fb07bd72038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007fb07b1b5fa0 RCX: 00007fb07af8e169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007fb07b1b5fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb07b1b5fa0 R15: 00007ffce0cdda48
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8ed3df20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x30/0x180 kernel/locking/lockdep.c:6764
8 locks held by kworker/u8:2/36:
4 locks held by kworker/u8:6/1336:
#0: ffff888143e83148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff888143e83148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x990/0x18e0 kernel/workqueue.c:3319
#1: ffffc900042ffc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900042ffc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9cb/0x18e0 kernel/workqueue.c:3319
#2: ffff88807e25a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_trylock_shared+0x22/0xf0 fs/super.c:562
#3: ffff88805d07d4c0 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x2a6/0x600 fs/jfs/inode.c:102
2 locks held by getty/5585:
#0: ffff88803187d0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x5bb/0x1700 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5840:
4 locks held by syz.3.32/6128:
2 locks held by syz.4.105/6626:
#0: ffff88807e25a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807e25a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff888143b6a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888143b6a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x270/0xb50 fs/fs-writeback.c:2831
2 locks held by syz.8.267/7920:
#0: ffff88807e25a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff88807e25a0e0 (&type->s_umount_key#74){++++}-{4:4}, at: super_lock+0x27c/0x400 fs/super.c:120
#1: ffff888143b6a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888143b6a7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x270/0xb50 fs/fs-writeback.c:2831
2 locks held by syz.9.375/8819:
2 locks held by dhcpcd/8863:
#0: ffff888012380258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff888012380258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3252
#1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x384/0x830 kernel/rcu/tree_exp.h:998
2 locks held by dhcpcd/8864:
#0: ffff888012124258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff888012124258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3252
#1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#1: ffffffff8ed43438 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x454/0x830 kernel/rcu/tree_exp.h:998
1 lock held by dhcpcd/8865:
#0: ffff88805b19a258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff88805b19a258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3252
1 lock held by dhcpcd/8866:
#0: ffff888029f52258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff888029f52258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3252
1 lock held by dhcpcd/8868:
#0: ffff888012610258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1651 [inline]
#0: ffff888012610258 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xcb0 net/packet/af_packet.c:3252
2 locks held by dhcpcd-run-hook/8871:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
nmi_cpu_backtrace+0x4ab/0x4e0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:437
kthread+0x7b7/0x940 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8819 Comm: syz.9.375 Not tainted 6.15.0-rc3-syzkaller-00019-gbc3372351d0c #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
RIP: 0010:trace_hardirqs_off+0x23/0x40 kernel/trace/trace_preemptirq.c:107
Code: 90 90 90 90 90 90 90 f3 0f 1e fa 53 48 8b 5c 24 08 48 89 df e8 5e 13 5d 0a 65 8b 05 57 66 9b 11 85 c0 74 06 5b c3 cc cc cc cc <65> c7 05 42 66 9b 11 01 00 00 00 48 89 df 5b e9 99 fe ff ff 66 0f
RSP: 0018:ffffc90003fd6e30 EFLAGS: 00000046
RAX: 0000000000000000 RBX: ffffffff8c2a7df3 RCX: 61c8864680b583eb
RDX: 0000000000000001 RSI: ffffffff8e63564b RDI: ffffffff8ca0e2c0
RBP: ffffc90003fd6ed0 R08: ffffc90003fd6fa7 R09: 0000000000000000
R10: ffffc90003fd6f80 R11: fffff520007fadf5 R12: dffffc0000000000
R13: 0000000000000246 R14: ffffffff9a9a3c70 R15: ffffc90003fd6e60
FS: 0000000000000000(0000) GS:ffff8881250cf000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffecbfb8098 CR3: 000000005ed7e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:108 [inline]
_raw_spin_lock_irqsave+0xb3/0x130 kernel/locking/spinlock.c:162
__debug_check_no_obj_freed lib/debugobjects.c:1088 [inline]
debug_check_no_obj_freed+0x245/0x590 lib/debugobjects.c:1129
free_pages_prepare mm/page_alloc.c:1269 [inline]
free_unref_folios+0x576/0x17e0 mm/page_alloc.c:2782
folios_put_refs+0x70a/0x800 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x595/0x1820 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x29d/0xa80 mm/shmem.c:1365
evict+0x4f9/0x9b0 fs/inode.c:810
__dentry_kill+0x20d/0x630 fs/dcache.c:660
dput+0x19f/0x2b0 fs/dcache.c:902
__fput+0x60b/0x9f0 fs/file_table.c:473
task_work_run+0x251/0x310 kernel/task_work.c:227
exit_task_work include/linux/task_work.h:40 [inline]
do_exit+0xa11/0x27f0 kernel/exit.c:953
do_group_exit+0x207/0x2c0 kernel/exit.c:1102
get_signal+0x1696/0x1730 kernel/signal.c:3034
arch_do_signal_or_restart+0x98/0x810 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
do_syscall_64+0x100/0x210 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7efd5bf8cc1f
Code: Unable to access opcode bytes at 0x7efd5bf8cbf5.
RSP: 002b:00007efd5ce94df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: 0000000000ba6000 RBX: 0000000001000000 RCX: 00007efd5bf8cc1f
RDX: 0000000001000000 RSI: 00007efd51800000 RDI: 0000000000000007
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000004427
R10: 0000000000000002 R11: 0000000000000293 R12: 0000000000000007
R13: 00007efd5ce94ef0 R14: 00007efd5ce94eb0 R15: 00007efd51800000