INFO: task syz.3.685:11256 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.685 state:D stack:22568 pid:11256 tgid:11254 ppid:5843 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
rt_mutex_schedule+0x77/0xf0 kernel/sched/core.c:7339
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1e04/0x25e0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xb5/0x160 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14f/0x750 kernel/locking/rwbase_rt.c:244
inode_lock include/linux/fs.h:869 [inline]
generic_file_write_iter+0xec/0x550 mm/filemap.c:4315
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x5d2/0xb40 fs/read_write.c:686
ksys_pwrite64 fs/read_write.c:793 [inline]
__do_sys_pwrite64 fs/read_write.c:801 [inline]
__se_sys_pwrite64 fs/read_write.c:798 [inline]
__x64_sys_pwrite64+0x196/0x220 fs/read_write.c:798
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: 0033:0x7fbf62fbebe9
RSP: 002b:00007fbf61226038 EFLAGS: 00000246 ORIG_RAX: 0000000000000012
RAX: ffffffffffffffda RBX: 00007fbf631f5fa0 RCX: 00007fbf62fbebe9
RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000006
RBP: 00007fbf63041e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000e7c R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbf631f6038 R14: 00007fbf631f5fa0 R15: 00007fff088eb298
Showing all locks held in the system:
2 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/13:
#0: ffff8881404fb138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff8881404fb138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff88805be960d0 (&type->s_umount_key#64){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
1 lock held by khungtaskd/39:
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by klogd/5195:
1 lock held by udevd/5206:
2 locks held by getty/5598:
#0: ffff88823bf688a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e832e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
1 lock held by udevd/5900:
1 lock held by udevd/5978:
#0: ffff888022147b68 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline]
#0: ffff888022147b68 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:848
2 locks held by syz-executor/6337:
6 locks held by syz-executor/8957:
#0: ffff88802497a4c8 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_release+0x1af/0x660 block/bdev.c:1128
#1: ffffffff8f040b98 (uevent_sock_mutex){+.+.}-{4:4}, at: uevent_net_broadcast_untagged lib/kobject_uevent.c:317 [inline]
#1: ffffffff8f040b98 (uevent_sock_mutex){+.+.}-{4:4}, at: kobject_uevent_net_broadcast+0x281/0x560 lib/kobject_uevent.c:410
#2: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#2: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#2: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: sock_def_readable+0xbe/0x560 net/core/sock.c:3561
#3: ffff8880328df358 (&ei->socket.wq.wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:44 [inline]
#3: ffff8880328df358 (&ei->socket.wq.wait){+.+.}-{3:3}, at: __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
#4: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#4: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#4: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: __rt_spin_lock kernel/locking/spinlock_rt.c:50 [inline]
#4: ffffffff8d9a8bc0 (rcu_read_lock){....}-{1:3}, at: rt_spin_lock+0x1bb/0x2c0 kernel/locking/spinlock_rt.c:57
#5: ffff88803672b218 (&ep->lock){++++}-{3:3}, at: ep_poll_callback+0xdb/0x8d0 fs/eventpoll.c:1346
2 locks held by syz.3.685/11256:
#0: ffff88805be96488 (sb_writers#19){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:3107 [inline]
#0: ffff88805be96488 (sb_writers#19){.+.+}-{0:0}, at: vfs_write+0x217/0xb40 fs/read_write.c:682
#1: ffff88805d3c17e8 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#1: ffff88805d3c17e8 (&sb->s_type->i_mutex_key#25){++++}-{4:4}, at: generic_file_write_iter+0xec/0x550 mm/filemap.c:4315
2 locks held by syz.3.685/11267:
2 locks held by syz.8.917/12938:
1 lock held by syz.6.919/12946:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 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: 20 Comm: rcuc/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:135 [inline]
RIP: 0010:memory_is_poisoned mm/kasan/generic.c:161 [inline]
RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline]
RIP: 0010:kasan_check_range+0x297/0x2c0 mm/kasan/generic.c:189
Code: 49 83 c3 04 eb 10 4d 01 f3 49 83 c3 05 eb 07 4d 01 f3 49 83 c3 06 4d 89 dc 4d 85 db 0f 84 44 ff ff ff 4d 01 d1 4d 39 cc 75 11 <41> 83 e0 07 45 0f be 09 45 39 c8 0f 8c 2b ff ff ff 0f b6 d2 e8 a0
RSP: 0018:ffffc90000197668 EFLAGS: 00000046
RAX: 00000000ffffff01 RBX: ffffffffffffffff RCX: ffffffff819caf41
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc900001976e0
RBP: ffffc90000197750 R08: ffffc900001976e3 R09: fffff52000032edc
R10: dffffc0000000000 R11: fffff52000032edc R12: fffff52000032edc
R13: ffff8880b883c088 R14: fffff52000032edd R15: 1ffff92000032edc
FS: 0000000000000000(0000) GS:ffff8881268c2000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3805262000 CR3: 00000000274e2000 CR4: 00000000003526f0
Call Trace:
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1301 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
do_raw_spin_lock+0x121/0x290 kernel/locking/spinlock_debug.c:116
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:111 [inline]
_raw_spin_lock_irqsave+0xb3/0xf0 kernel/locking/spinlock.c:162
rt_mutex_slowunlock+0xb0/0x8a0 kernel/locking/rtmutex.c:1417
spin_unlock include/linux/spinlock_rt.h:105 [inline]
refill_obj_stock+0x2c2/0x470 mm/memcontrol.c:3059
__memcg_slab_free_hook+0x127/0x3d0 mm/memcontrol.c:3216
memcg_slab_free_hook mm/slub.c:2242 [inline]
slab_free mm/slub.c:4677 [inline]
kmem_cache_free+0x344/0x510 mm/slub.c:4782
rcu_do_batch kernel/rcu/tree.c:2605 [inline]
rcu_core kernel/rcu/tree.c:2861 [inline]
rcu_cpu_kthread+0xbf3/0x1b50 kernel/rcu/tree.c:2949
smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
kthread+0x711/0x8a0 kernel/kthread.c:463
ret_from_fork+0x3f9/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245