INFO: task syz.2.22:4517 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.22 state:D stack:25320 pid:4517 ppid:4411 flags:0x00004000
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5244 [inline]
__schedule+0x10ec/0x40b0 kernel/sched/core.c:6561
schedule+0xb9/0x180 kernel/sched/core.c:6637
rwsem_down_write_slowpath+0xbed/0x1090 kernel/locking/rwsem.c:1189
mmap_write_lock include/linux/mmap_lock.h:71 [inline]
exit_mmap+0x20f/0x8e0 mm/mmap.c:3258
__mmput+0x118/0x3c0 kernel/fork.c:1200
exit_mm+0x1e6/0x2c0 kernel/exit.c:565
do_exit+0x8c1/0x2400 kernel/exit.c:867
do_group_exit+0x217/0x2d0 kernel/exit.c:1022
__do_sys_exit_group kernel/exit.c:1033 [inline]
__se_sys_exit_group kernel/exit.c:1031 [inline]
__x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fadf518f749
RSP: 002b:00007ffc842ab4e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fadf518f749
RDX: 0000000000000064 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007ffc842ab54c R08: 00000005842ab5df R09: 00000000000927c0
R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000001
R13: 00000000000927c0 R14: 0000000000024192 R15: 00007ffc842ab5a0
</TASK>
Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8cb2b630 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8cb2be50 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8cb2aca0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513
5 locks held by kworker/u4:4/47:
#0: ffff8880b8e3aad8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:537
#1: ffff8880b8e27848 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x398/0x6d0 kernel/sched/psi.c:999
#2: ffff8880b8e28418 (&base->lock){-.-.}-{2:2}, at: lock_timer_base+0x123/0x270 kernel/time/timer.c:999
#3: ffffffff96ebba08 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_object_activate+0x6a/0x490 lib/debugobjects.c:698
#4: ffffffff96ed5a90 (&obj_hash[i].lock){-.-.}-{2:2}, at: __debug_check_no_obj_freed lib/debugobjects.c:968 [inline]
#4: ffffffff96ed5a90 (&obj_hash[i].lock){-.-.}-{2:2}, at: debug_check_no_obj_freed+0x136/0x530 lib/debugobjects.c:1009
1 lock held by dhcpcd/3932:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: copy_process+0x248b/0x4020 kernel/fork.c:2446
2 locks held by getty/4024:
#0: ffff88814d6bb098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41b/0x1380 drivers/tty/n_tty.c:2198
1 lock held by udevd/4313:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827
1 lock held by udevd/4367:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827
1 lock held by syz-executor/4404:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827
2 locks held by syz-executor/4406:
#0: ffffffff8cbc5010 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mmap kernel/fork.c:593 [inline]
#0: ffffffff8cbc5010 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1541 [inline]
#0: ffffffff8cbc5010 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x2a9/0x15c0 kernel/fork.c:1590
#1: ffff8880279df958 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock_killable include/linux/mmap_lock.h:87 [inline]
#1: ffff8880279df958 (&mm->mmap_lock){++++}-{3:3}, at: dup_mmap kernel/fork.c:594 [inline]
#1: ffff8880279df958 (&mm->mmap_lock){++++}-{3:3}, at: dup_mm kernel/fork.c:1541 [inline]
#1: ffff8880279df958 (&mm->mmap_lock){++++}-{3:3}, at: copy_mm+0x2c3/0x15c0 kernel/fork.c:1590
7 locks held by syz-executor/4418:
#0: ffff888023d52460 (sb_writers#11){.+.+}-{0:0}, at: vfs_write+0x256/0x960 fs/read_write.c:580
#1: ffff88801e780488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x1e3/0x520 fs/kernfs/file.c:343
#2: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_lock include/linux/cgroup.h:442 [inline]
#2: ffffffff8cb536e8 (cgroup_mutex){+.+.}-{3:3}, at: cgroup_kn_lock_live+0xee/0x230 kernel/cgroup/cgroup.c:1700
#3: ffffffff8c9c7b30 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2476 [inline]
#3: ffffffff8c9c7b30 (cpu_hotplug_lock){++++}-{0:0}, at: cgroup_procs_write_start+0x183/0x600 kernel/cgroup/cgroup.c:2982
#4: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_attach_lock kernel/cgroup/cgroup.c:2478 [inline]
#4: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: cgroup_procs_write_start+0x199/0x600 kernel/cgroup/cgroup.c:2982
#5: ffffffff8cb61d68 (cpuset_mutex){+.+.}-{3:3}, at: cpuset_attach+0xac/0x540 kernel/cgroup/cpuset.c:2647
#6: ffff8880293e62d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#6: ffff8880293e62d8 (&mm->mmap_lock){++++}-{3:3}, at: mpol_rebind_mm+0xbe/0x370 mm/mempolicy.c:386
1 lock held by udevd/4497:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827
2 locks held by kworker/u4:8/4515:
1 lock held by syz.2.22/4517:
#0: ffff88807e93ea58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff88807e93ea58 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x20f/0x8e0 mm/mmap.c:3258
1 lock held by syz.3.62/4582:
#0: ffff88801746a6d8 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline]
#0: ffff88801746a6d8 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x20f/0x8e0 mm/mmap.c:3258
1 lock held by syz.1.67/4587:
#0: ffffffff8cb538d0 (cgroup_threadgroup_rwsem){++++}-{0:0}, at: do_exit+0x578/0x2400 kernel/exit.c:827
=============================================
NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
<TASK>
dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
nmi_cpu_backtrace+0x3f4/0x470 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xeee/0xf30 kernel/hung_task.c:377
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 47 Comm: kworker/u4:4 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:check_preemption_disabled+0x3/0x110 lib/smp_processor_id.c:13
Code: bc 8c 4c 89 f6 e8 9d d1 16 fa e9 6e ff ff ff 00 00 cc cc 00 00 cc cc 48 c7 c7 00 f7 de 8a 48 c7 c6 40 f7 de 8a eb 00 55 41 57 <41> 56 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65
RSP: 0018:ffffc90000b87828 EFLAGS: 00000046
RAX: 0000000080000001 RBX: 0000000100001452 RCX: 71bd17b229c33300
RDX: 0000000000000000 RSI: ffffffff8adef740 RDI: ffffffff8adef700
RBP: ffffc90000b879f0 R08: dffffc0000000000 R09: ffffc90000b87a80
R10: fffff52000170f58 R11: 1ffff92000170f50 R12: ffffc90000b87900
R13: 0000000000000002 R14: 0000000000000200 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0d15d1e000 CR3: 000000000c88e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
crng_make_state+0x15e/0xa90 drivers/char/random.c:328
_get_random_bytes+0xd2/0x210 drivers/char/random.c:366
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:775 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline]
nsim_dev_trap_report_work+0x642/0xaf0 drivers/net/netdevsim/dev.c:851
process_one_work+0x898/0x1160 kernel/workqueue.c:2292
worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
kthread+0x29d/0x330 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
</TASK>