INFO: task kworker/u4:12:4802 blocked for more than 145 seconds.
Not tainted 5.15.176-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:12 state:D stack:22712 pid: 4802 ppid: 2 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:0)
Call Trace:
context_switch kernel/sched/core.c:5027 [inline]
__schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
schedule+0x11b/0x1f0 kernel/sched/core.c:6456
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6515
__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
exfat_write_inode+0x65/0x110 fs/exfat/inode.c:87
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: ffffffff8cb1fce0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
2 locks held by udevd/3545:
#0: ffff8880204f5918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xfb/0x790 block/bdev.c:912
#1: ffff888020642468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x4d/0x1f0 drivers/block/loop.c:2070
1 lock held by dhcpcd/3837:
#0: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: netlink_dump+0xd5/0xca0 net/netlink/af_netlink.c:2212
2 locks held by getty/3926:
#0: ffff88802bdfd098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002cd62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
3 locks held by syz-executor/4165:
3 locks held by kworker/u4:6/4253:
2 locks held by kworker/1:15/4556:
#0: ffff888017472138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc900030efd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
3 locks held by kworker/1:16/4557:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc9000319fd20 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#2: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:18/4559:
#0: ffff88814c9a0138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90002ecfd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113
3 locks held by kworker/0:16/4635:
#0: ffff88814c9a0138 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003247d20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x1720 net/ipv6/addrconf.c:4113
4 locks held by kworker/u4:12/4802:
#0: ffff8881439c4138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003cafd20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffff8880623cc0e0 (&type->s_umount_key#85){++++}-{3:3}, at: trylock_super+0x1b/0xf0 fs/super.c:418
#3: ffff88807504a0e0 (&sbi->s_lock#2){+.+.}-{3:3}, at: exfat_write_inode+0x65/0x110 fs/exfat/inode.c:87
1 lock held by syz-executor/5168:
#0: ffff8880204f5918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x14d/0xa50 block/bdev.c:817
1 lock held by syz-executor/6807:
#0: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
3 locks held by kworker/0:20/6941:
#0: ffff888017470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
#1: ffffc90003edfd20 (deferred_process_work){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
#2: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: switchdev_deferred_process_work+0xa/0x20 net/switchdev/switchdev.c:74
1 lock held by syz.7.518/7039:
#0: ffff888050d440e0 (&type->s_umount_key#52/1){+.+.}-{3:3}, at: alloc_super+0x210/0x940 fs/super.c:229
2 locks held by syz.3.519/7042:
#0: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8dc42188 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
#1: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
#1: ffffffff8cb242a8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x350/0x740 kernel/rcu/tree_exp.h:845
=============================================
NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
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:210 [inline]
watchdog+0xe72/0xeb0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4477 Comm: kworker/u4:10 Not tainted 5.15.176-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x1550/0x1ff0 kernel/locking/lockdep.c:5039
Code: 48 b9 00 00 00 00 00 fc ff df 0f b6 04 08 84 c0 0f 85 d7 09 00 00 83 3d e5 b5 a7 0c 00 74 62 31 f6 89 f0 48 81 c4 88 00 00 00 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 e8 e0 be ad 02 85 c0 74 e1 48 c7
RSP: 0018:ffffc9000133f988 EFLAGS: 00000086
RAX: 0000000000000001 RBX: ffff888079370ae0 RCX: ffffffff81638982
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff9098a1e8
RBP: eef609facd7892c3 R08: dffffc0000000000 R09: fffffbfff213143e
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000002
R13: ffff888079370ae8 R14: ffff888079370000 R15: ffff888079370b60
FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f74d1866ab8 CR3: 00000000236ae000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x1db/0x4f0 kernel/locking/lockdep.c:5623
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
_raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
spin_lock_bh include/linux/spinlock.h:368 [inline]
batadv_nc_purge_paths+0xe8/0x3b0 net/batman-adv/network-coding.c:446
batadv_nc_worker+0x30b/0x5b0 net/batman-adv/network-coding.c:726
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