INFO: task syz.3.94:6960 blocked for more than 143 seconds.
Not tainted 6.15.0-rc5-syzkaller-00136-g9c69f8884904 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.94 state:D stack:26920 pid:6960 tgid:6955 ppid:5821 task_flags:0x400040 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_read_slowpath+0x552/0x880 kernel/locking/rwsem.c:1084
__down_read_common kernel/locking/rwsem.c:1248 [inline]
__down_read kernel/locking/rwsem.c:1261 [inline]
down_read+0x98/0x2e0 kernel/locking/rwsem.c:1526
inode_lock_shared include/linux/fs.h:877 [inline]
lookup_slow+0x46/0x70 fs/namei.c:1833
walk_component+0x2d2/0x400 fs/namei.c:2138
lookup_last fs/namei.c:2636 [inline]
path_lookupat+0x163/0x430 fs/namei.c:2660
filename_lookup+0x212/0x570 fs/namei.c:2689
user_path_at+0x3a/0x60 fs/namei.c:3120
do_mount fs/namespace.c:4221 [inline]
__do_sys_mount fs/namespace.c:4435 [inline]
__se_sys_mount+0x2d3/0x410 fs/namespace.c:4412
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4a17f8e969
RSP: 002b:00007f4a18e7f038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f4a181b6080 RCX: 00007f4a17f8e969
RDX: 0000200000000000 RSI: 0000200000000380 RDI: 0000000000000000
RBP: 00007f4a18010ab1 R08: 0000200000000400 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f4a181b6080 R15: 00007fff46c2a7b8
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3b860 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
4 locks held by kworker/u8:5/81:
#0: ffff8881412e5148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8881412e5148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000242fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000242fc60 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffff888030c400e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:562
#3: ffff88805bff6730 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
2 locks held by getty/5592:
#0: ffff888035f810a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.3.94/6956:
1 lock held by syz.3.94/6960:
#0: ffff88805bff6ae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:877 [inline]
#0: ffff88805bff6ae0 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1833
1 lock held by syz-executor/7665:
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#0: ffffffff8df41338 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz.7.184/7927:
#0: ffff888030c400e0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:58 [inline]
#0: ffff888030c400e0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:120
#1: ffff888142fd87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888142fd87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
2 locks held by kworker/u8:20/8719:
#0: ffff8880b88399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
#1: ffff8880b8823b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
2 locks held by syz.3.297/9364:
2 locks held by dhcpcd-run-hook/9401:
#0: ffff8880b89399d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:605
#1: ffff8880b8923b08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
2 locks held by sed/9402:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc5-syzkaller-00136-g9c69f8884904 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
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:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 1155 Comm: kworker/u8:7 Not tainted 6.15.0-rc5-syzkaller-00136-g9c69f8884904 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:check_wait_context kernel/locking/lockdep.c:-1 [inline]
RIP: 0010:__lock_acquire+0x35f/0xd20 kernel/locking/lockdep.c:5185
Code: 00 75 19 90 48 c7 c7 be 13 92 8d 48 c7 c6 46 90 81 8d e8 14 08 e6 ff 90 0f 0b 90 90 90 31 c0 48 8b 3c 24 0f b6 98 c4 00 00 00 <41> 8b 47 20 25 ff 1f 00 00 48 0f a3 05 a0 73 db 11 73 17 48 69 c0
RSP: 0018:ffffc90003eff3f8 EFLAGS: 00000006
RAX: ffffffff931a9c58 RBX: 0000000000000003 RCX: 0000000000000007
RDX: 0000000000020000 RSI: 0000000000000000 RDI: ffff888026963c00
RBP: ffff8880269646f0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff8171a9f5 R12: 0000000000020000
R13: 0000000000000000 R14: 0000000000000007 R15: ffff888026964790
FS: 0000000000000000(0000) GS:ffff888126100000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000563446add950 CR3: 000000003449c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5866
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
unpoison_slab_object mm/kasan/common.c:319 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:345
kasan_slab_alloc include/linux/kasan.h:250 [inline]
slab_post_alloc_hook mm/slub.c:4147 [inline]
slab_alloc_node mm/slub.c:4196 [inline]
kmem_cache_alloc_node_noprof+0x1bb/0x3c0 mm/slub.c:4248
__alloc_skb+0x112/0x2d0 net/core/skbuff.c:658
alloc_skb include/linux/skbuff.h:1340 [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:3238 [inline]
process_scheduled_works+0xadb/0x17a0 kernel/workqueue.c:3319
worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400
kthread+0x70e/0x8a0 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