INFO: task syz.4.350:9146 blocked for more than 143 seconds.
INFO: task syz.4.350:9146 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.350 state:D stack:25992 pid:9146 tgid:9142 ppid:8436 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5504 [inline]
__schedule+0x16dc/0x5500 kernel/sched/core.c:7228
__schedule_loop kernel/sched/core.c:7307 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7603
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1670 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1747 [inline]
__rt_mutex_slowlock_locked+0x1f84/0x25b0 kernel/locking/rtmutex.c:1787
__rwbase_read_lock+0xc3/0x180 kernel/locking/rwbase_rt.c:114
rwbase_read_lock kernel/locking/rwbase_rt.c:147 [inline]
__down_read kernel/locking/rwsem.c:1502 [inline]
down_read+0x132/0x200 kernel/locking/rwsem.c:1576
__super_lock fs/super.c:60 [inline]
super_lock+0x2d6/0x3d0 fs/super.c:122
user_get_super+0xc8/0x120 fs/super.c:941
quotactl_block fs/quota/quota.c:889 [inline]
__do_sys_quotactl fs/quota/quota.c:955 [inline]
__se_sys_quotactl+0x538/0x9a0 fs/quota/quota.c:917
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcc81d6ce59
RSP: 002b:00007fcc7ffbe028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fcc81fe5fa0 RCX: 00007fcc81d6ce59
RDX: 0000000000000000 RSI: 0000200000000000 RDI: ffffffff80000801
RBP: 00007fcc81e02e6f R08: 0000000000000000 R09: 0000000000000000
R10: 00002000000002c0 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcc81fe6038 R14: 00007fcc81fe5fa0 R15: 00007ffd5b3474e8
INFO: lockdep is turned off.
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 38 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:122
nmi_trigger_cpumask_backtrace+0x17a/0x380 lib/nmi_backtrace.c:65
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
__sys_info lib/sys_info.c:157 [inline]
sys_info+0x135/0x170 lib/sys_info.c:165
check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline]
watchdog+0xfd7/0x1030 kernel/hung_task.c:561
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
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: 1125 Comm: kworker/u8:8 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Workqueue: events_unbound nsim_dev_trap_report_work
RIP: 0010:check_preemption_disabled+0x3/0xe0 lib/smp_processor_id.c:13
Code: a9 8b 48 c7 c6 60 29 a9 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 53 65 8b 05 d7 9d 4a 07 65 8b 0d cc 9d 4a 07 f7 c1 ff ff ff
RSP: 0018:ffffc90006257480 EFLAGS: 00000283
RAX: 0000000000000000 RBX: ffffffff9013582a RCX: ffffffff8f9efc54
RDX: ffffffff90135826 RSI: ffffffff8ba92960 RDI: ffffffff8ba92920
RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000
R10: ffffc90006257618 R11: ffffffff81afe1e0 R12: dffffc0000000000
R13: ffffffff8176a1ff R14: ffffffff8dfc2f80 R15: 1ffff92000c4aeb9
FS: 0000000000000000(0000) GS:ffff88812611d000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ce2c941950 CR3: 000000003e2f6000 CR4: 00000000003526f0
Call Trace:
rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:752
trace_lock_release include/trace/events/lock.h:68 [inline]
lock_release+0x4b/0x3c0 kernel/locking/lockdep.c:5879
rcu_lock_release include/linux/rcupdate.h:310 [inline]
rcu_read_unlock include/linux/rcupdate.h:871 [inline]
class_rcu_destructor include/linux/rcupdate.h:1183 [inline]
unwind_next_frame+0x1baa/0x2550 arch/x86/kernel/unwind_orc.c:709
arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
unpoison_slab_object mm/kasan/common.c:340 [inline]
__kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4612 [inline]
slab_alloc_node mm/slub.c:4945 [inline]
kmem_cache_alloc_node_noprof+0x3eb/0x670 mm/slub.c:5017
__alloc_skb+0x1d7/0x7a0 net/core/skbuff.c:704
alloc_skb include/linux/skbuff.h:1384 [inline]
nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:819 [inline]
nsim_dev_trap_report drivers/net/netdevsim/dev.c:876 [inline]
nsim_dev_trap_report_work+0x2b1/0xcb0 drivers/net/netdevsim/dev.c:922
process_one_work kernel/workqueue.c:3322 [inline]
process_scheduled_works+0xa8e/0x14e0 kernel/workqueue.c:3405
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3486
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245