INFO: task syz.9.7332:3977 blocked for more than 143 seconds.
Not tainted 6.16.0-rc2-next-20250619-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.7332 state:D stack:27376 pid:3977 tgid:3944 ppid:30426 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5313 [inline]
__schedule+0x16f5/0x4d00 kernel/sched/core.c:6696
__schedule_loop kernel/sched/core.c:6774 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6789
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6846
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:869 [inline]
vfs_unlink+0xf2/0x650 fs/namei.c:4575
do_unlinkat+0x345/0x560 fs/namei.c:4650
__do_sys_unlink fs/namei.c:4696 [inline]
__se_sys_unlink fs/namei.c:4694 [inline]
__x64_sys_unlink+0x47/0x50 fs/namei.c:4694
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4d8418e929
RSP: 002b:00007f4d81cb3038 EFLAGS: 00000246 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 00007f4d843b6160 RCX: 00007f4d8418e929
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000200000000180
RBP: 00007f4d84210b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f4d843b6160 R15: 00007ffc4c6bf148
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13ef20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ef20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ef20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:3/49:
#0: ffff888143295948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#0: ffff888143295948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3322
#1: ffffc90000b97bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3215 [inline]
#1: ffffc90000b97bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3322
#2: ffff8880497240e0 (&type->s_umount_key#60){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88805b19ce98 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_map_blocks+0x315/0xe80 fs/xfs/xfs_aops.c:330
6 locks held by kworker/0:2/1210:
#0: ffff8880b8639f58 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xad/0x140 kernel/sched/core.c:614
#1: ffff8880b8623f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x314/0x6d0 kernel/sched/psi.c:979
#2: ffffffff99d16d80 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_deactivate+0x9a/0x250 lib/debugobjects.c:873
#3: ffff88801a45d818 (&vn->pool_lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
#3: ffff88801a45d818 (&vn->pool_lock){+.+.}-{3:3}, at: node_pool_add_va mm/vmalloc.c:1909 [inline]
#3: ffff88801a45d818 (&vn->pool_lock){+.+.}-{3:3}, at: purge_vmap_node+0x74d/0x8f0 mm/vmalloc.c:2272
#4: ffff8880b863fcd8 (&pcp->lock){+.+.}-{3:3}, at: spin_trylock include/linux/spinlock.h:361 [inline]
#4: ffff8880b863fcd8 (&pcp->lock){+.+.}-{3:3}, at: __free_frozen_pages+0x76a/0xe70 mm/page_alloc.c:2732
#5: ffffffff99af0388 (&____s->seqcount#2){----}-{0:0}, at: ktime_get+0x3e/0x1f0 kernel/time/timekeeping.c:776
2 locks held by getty/30367:
#0: ffff88814e0980a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900032772f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.9.7332/3976:
#0: ffff888049724428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805b19d0b0 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88805b19d0b0 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: vfs_setxattr+0x144/0x2f0 fs/xattr.c:320
#2: ffff888049724618 (sb_internal#2){.+.+}-{0:0}, at: xfs_trans_alloc_inode+0x13c/0x4a0 fs/xfs/xfs_trans.c:1096
#3: ffff88805b19ce98 (&xfs_nondir_ilock_class){++++}-{4:4}, at: xfs_trans_alloc_inode+0x161/0x4a0 fs/xfs/xfs_trans.c:1102
3 locks held by syz.9.7332/3977:
#0: ffff888049724428 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88805b19e7f0 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#1: ffff88805b19e7f0 (&inode->i_sb->s_type->i_mutex_dir_key/1){+.+.}-{4:4}, at: do_unlinkat+0x1c7/0x560 fs/namei.c:4637
#2: ffff88805b19d0b0 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#2: ffff88805b19d0b0 (&sb->s_type->i_mutex_key#22){++++}-{4:4}, at: vfs_unlink+0xf2/0x650 fs/namei.c:4575
2 locks held by syz.5.7694/5660:
1 lock held by syz.6.7695/5665:
#0: ffffffff8e144a38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:311 [inline]
#0: ffffffff8e144a38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:967
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc2-next-20250619-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Not tainted 6.16.0-rc2-next-20250619-syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:validate_chain+0x29c/0x2140 kernel/locking/lockdep.c:3918
Code: 3f 42 8d 04 b0 89 45 00 e8 31 d6 ff ff 44 39 35 d2 aa 08 14 73 53 e8 33 ff 24 03 89 c3 e8 dc 9a ff ff 85 db 0f 85 56 02 00 00 <83> 3d 0d 30 03 0e 00 0f 84 a2 17 00 00 b8 01 00 00 00 65 48 8b 0d
RSP: 0018:ffffc900001171f0 EFLAGS: 00000087
RAX: 0000000000020007 RBX: 0000000000000004 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff88801ce96590 RDI: ffff88801ce95a00
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8172ac65
R10: ffffc90000117558 R11: ffffffff81ad0f60 R12: 00000000f1a8b926
R13: ffff88801ce964f0 R14: ffff88801ce96590 R15: 2ad5ab4f82428a40
FS: 0000000000000000(0000) GS:ffff888125c28000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c3d4658 CR3: 000000003059a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
rcu_read_lock include/linux/rcupdate.h:841 [inline]
class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
unwind_next_frame+0xc2/0x2390 arch/x86/kernel/unwind_orc.c:479
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394
kasan_kmalloc include/linux/kasan.h:260 [inline]
__do_kmalloc_node mm/slub.c:4364 [inline]
__kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4383
kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601
__alloc_skb+0x142/0x2d0 net/core/skbuff.c:670
alloc_skb include/linux/skbuff.h:1336 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:851
process_one_work kernel/workqueue.c:3239 [inline]
process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3322
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3403
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245