INFO: task syz.2.67:6497 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.67 state:D stack:27944 pid:6497 tgid:6475 ppid:5834 task_flags:0x400040 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_nested include/linux/fs.h:915 [inline]
filename_create+0x1f8/0x3c0 fs/namei.c:4139
do_mkdirat+0xa0/0x590 fs/namei.c:4391
__do_sys_mkdirat fs/namei.c:4416 [inline]
__se_sys_mkdirat fs/namei.c:4414 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4414
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: 0033:0x7f8d1293d617
RSP: 002b:00007f8d10b5be68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f8d10b5bef0 RCX: 00007f8d1293d617
RDX: 00000000000001ff RSI: 0000200000000240 RDI: 00000000ffffff9c
RBP: 0000200000000000 R08: 00002000000000c0 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000200000000240
R13: 00007f8d10b5beb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
6 locks held by kworker/u8:2/37:
1 lock held by khungtaskd/39:
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:4/67:
2 locks held by kworker/u8:7/998:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900044ffbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900044ffbc0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
2 locks held by kworker/u8:11/3045:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000c9f7bc0 (connector_reaper_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000c9f7bc0 (connector_reaper_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
1 lock held by udevd/5205:
2 locks held by getty/5592:
#0: ffff88823bf868a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e8b2e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x444/0x1410 drivers/tty/n_tty.c:2222
3 locks held by udevd/6027:
1 lock held by udevd/6057:
#0: ffff888022242ee8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:885 [inline]
#0: ffff888022242ee8 (&sb->s_type->i_mutex_key#7){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:851
4 locks held by kworker/u8:13/6089:
#0: ffff8881404ca938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff8881404ca938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000a447bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000a447bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
#2: ffff888031afc0d0 (&type->s_umount_key#61){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888060954698 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
4 locks held by syz.2.67/6476:
2 locks held by syz.2.67/6497:
#0: ffff888031afc488 (sb_writers#14){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888060954a68 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:915 [inline]
#1: ffff888060954a68 (&type->i_mutex_dir_key#9/1){+.+.}-{4:4}, at: filename_create+0x1f8/0x3c0 fs/namei.c:4139
2 locks held by syz.4.310/7975:
3 locks held by syz.1.311/7980:
3 locks held by syz.3.312/7984:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 39 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x436/0x7d0 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 7981 Comm: syz.5.309 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:count_memcg_events+0xb0/0x270 mm/memcontrol.c:845
Code: e8 48 c1 e8 03 80 3c 28 00 74 08 4c 89 ef e8 67 ca fc ff 4d 8b 6d 00 41 80 ff 19 0f 83 18 01 00 00 65 4b 01 9c fd 50 01 00 00 <4c> 89 f7 89 de 44 89 e2 e8 93 ed ff ff 0f 1f 44 00 00 65 8b 05 9b
RSP: 0000:ffffc9000c29fbf8 EFLAGS: 00000216
RAX: 1ffff11004e2a434 RBX: 0000000000000001 RCX: 7bb160b86123ac00
RDX: 0000000000000001 RSI: ffffffff8b17c7e0 RDI: ffffffff8b621680
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1e3ac67 R12: 0000000000000001
R13: 0000607ed93d0f80 R14: ffff888027151a80 R15: 000000000000000c
FS: 0000555557a57500(0000) GS:ffff8881269bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00002000000061a0 CR3: 00000000275b4000 CR4: 00000000003526f0
Call Trace:
count_memcg_events_mm include/linux/memcontrol.h:980 [inline]
count_memcg_event_mm+0x14c/0x260 include/linux/memcontrol.h:987
mm_account_fault mm/memory.c:6229 [inline]
handle_mm_fault+0x2fd8/0x3400 mm/memory.c:6390
do_user_addr_fault+0xa81/0x1390 arch/x86/mm/fault.c:1336
handle_page_fault arch/x86/mm/fault.c:1476 [inline]
exc_page_fault+0x76/0xf0 arch/x86/mm/fault.c:1532
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x7f33c4706c47
Code: ce 48 ff c7 48 01 fe 48 8d 54 11 80 0f 1f 80 00 00 00 00 c5 fe 6f 0e c5 fe 6f 56 20 c5 fe 6f 5e 40 c5 fe 6f 66 60 48 83 ee 80 fd 7f 0f c5 fd 7f 57 20 c5 fd 7f 5f 40 c5 fd 7f 67 60 48 83 ef
RSP: 002b:00007fff9bb78018 EFLAGS: 00010207
RAX: 0000200000006180 RBX: 0000000000000004 RCX: 0000200000006180
RDX: 0000200000006809 RSI: 0000001b31c22427 RDI: 00002000000061a0
RBP: 00007f33c4997da0 R08: 0000000000000000 R09: 000000000000001c
R10: 0000000000000000 R11: 0000000000000001 R12: 00007f33c4995fac
R13: 00007f33c4995fa0 R14: fffffffffffffffe R15: 00007fff9bb78130