INFO: task syz.4.309:9969 blocked for more than 143 seconds.
Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.309 state:D stack:19448 pid:9969 tgid:9959 ppid:5831 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5378 [inline]
__schedule+0x18bc/0x4c40 kernel/sched/core.c:6765
__schedule_loop kernel/sched/core.c:6842 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6857
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914
rwsem_down_write_slowpath+0xeee/0x13b0 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1d7/0x220 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:877 [inline]
vfs_unlink+0xe4/0x650 fs/namei.c:4514
do_unlinkat+0x4ae/0x830 fs/namei.c:4589
__do_sys_unlink fs/namei.c:4637 [inline]
__se_sys_unlink fs/namei.c:4635 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:4635
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4e17f8d169
RSP: 002b:00007f4e18ead038 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f4e181a6080 RCX: 00007f4e17f8d169
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000400000000100
RBP: 00007f4e1800e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4e181a6080 R15: 00007ffd19ce09b8
Showing all locks held in the system:
1 lock held by khungtaskd/30:
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8eb392e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746
2 locks held by kworker/u8:3/52:
2 locks held by getty/5579:
#0: ffff8880311de0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211
1 lock held by syz-executor/5833:
#0: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
#0: ffffffff8eb3e7b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x820 kernel/rcu/tree_exp.h:996
2 locks held by kworker/u8:8/8093:
3 locks held by syz.4.309/9969:
#0: ffff88804a402420 (sb_writers#20){.+.+}-{0:0}, at: mnt_want_write+0x3f/0x90 fs/namespace.c:547
#1: ffff88807a620910 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:912 [inline]
#1: ffff88807a620910 (&sb->s_type->i_mutex_key#25/1){+.+.}-{4:4}, at: do_unlinkat+0x26a/0x830 fs/namei.c:4576
#2: ffff88807a6202a0 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: inode_lock include/linux/fs.h:877 [inline]
#2: ffff88807a6202a0 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: vfs_unlink+0xe4/0x650 fs/namei.c:4514
2 locks held by syz.4.309/10006:
2 locks held by syz.8.547/15171:
#0: ffffffff8f2576e8 (bio_slab_lock){+.+.}-{4:4}, at: bio_put_slab block/bio.c:140 [inline]
#0: ffffffff8f2576e8 (bio_slab_lock){+.+.}-{4:4}, at: bioset_exit+0x42f/0x650 block/bio.c:1662
#1: ffffffff8eb3e680 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x4c/0x530 kernel/rcu/tree.c:3741
2 locks held by syz.9.551/15276:
2 locks held by syz.3.552/15293:
2 locks held by dhcpcd-run-hook/15307:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
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+0x49c/0x4d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline]
watchdog+0x1058/0x10a0 kernel/hung_task.c:399
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8093 Comm: kworker/u8:8 Not tainted 6.14.0-rc5-syzkaller-00023-gbb2281fb05e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__preempt_count_add kernel/rcu/tree.c:712 [inline]
RIP: 0010:rcu_is_watching+0x8/0xb0 kernel/rcu/tree.c:715
Code: 7f 03 eb cd 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 41 57 41 56 <53> 65 ff 05 a8 a7 5c 7e e8 cb 8d 59 0a 89 c3 83 f8 08 73 7a 49 bf
RSP: 0018:ffffc90002eb7aa0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff8880601e8000
RDX: ffff8880601e8000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000000 R08: ffffffff8bcbfefe R09: 1ffffffff28a2908
R10: dffffc0000000000 R11: fffffbfff28a2909 R12: ffff88804ba78d80
R13: 0000000000000243 R14: ffff888032a073c0 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc17f92fb4 CR3: 0000000032c1e000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_unlock include/linux/rcupdate.h:878 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0x207/0x610 net/batman-adv/network-coding.c:719
process_one_work kernel/workqueue.c:3238 [inline]
process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
worker_thread+0x870/0xd30 kernel/workqueue.c:3400
kthread+0x7a9/0x920 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244