INFO: task syz.4.101:6456 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.101 state:D stack:27120 pid:6456 tgid:6446 ppid:5801 task_flags:0x400040 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5298 [inline]
__schedule+0x1553/0x5240 kernel/sched/core.c:6911
__schedule_loop kernel/sched/core.c:6993 [inline]
rt_mutex_schedule+0x76/0xf0 kernel/sched/core.c:7289
rt_mutex_slowlock_block kernel/locking/rtmutex.c:1647 [inline]
__rt_mutex_slowlock kernel/locking/rtmutex.c:1721 [inline]
__rt_mutex_slowlock_locked+0x1f8f/0x25c0 kernel/locking/rtmutex.c:1760
rt_mutex_slowlock+0xbd/0x170 kernel/locking/rtmutex.c:1800
__rt_mutex_lock kernel/locking/rtmutex.c:1815 [inline]
rwbase_write_lock+0x14d/0x730 kernel/locking/rwbase_rt.c:244
inode_lock include/linux/fs.h:1028 [inline]
open_last_lookups fs/namei.c:4586 [inline]
path_openat+0xb5e/0x38a0 fs/namei.c:4833
do_file_open+0x23e/0x4a0 fs/namei.c:4865
do_sys_openat2+0x113/0x200 fs/open.c:1366
do_sys_open fs/open.c:1372 [inline]
__do_sys_openat fs/open.c:1388 [inline]
__se_sys_openat fs/open.c:1383 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1383
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fdfaab5c819
RSP: 002b:00007fdfa8d8d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fdfaadd6090 RCX: 00007fdfaab5c819
RDX: 000000000000275a RSI: 0000200000000200 RDI: ffffffffffffff9c
RBP: 00007fdfaabf2c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdfaadd6128 R14: 00007fdfaadd6090 R15: 00007ffedf19e8e8
Showing all locks held in the system:
5 locks held by kworker/u8:0/12:
4 locks held by kworker/u8:1/13:
#0: ffff88801f2f0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#0: ffff88801f2f0138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3359
#1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3252 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3359
#2: ffff88805d4460d0 (&type->s_umount_key#58){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff88805f684fe8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by khungtaskd/37:
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8ddcb980 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5553:
#0: ffff8880374350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90003e762e0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x462/0x13c0 drivers/tty/n_tty.c:2211
1 lock held by udevd/5947:
4 locks held by syz.4.101/6447:
2 locks held by syz.4.101/6456:
#0: ffff88805d446480 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88805f6853b8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff88805f6853b8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:4586 [inline]
#1: ffff88805f6853b8 (&type->i_mutex_dir_key#10){++++}-{4:4}, at: path_openat+0xb5e/0x38a0 fs/namei.c:4833
2 locks held by syz.8.323/8127:
#0: ffff88805d4460d0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88805d4460d0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff888025bfa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:398 [inline]
#1: ffff888025bfa8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x209/0xc30 fs/fs-writeback.c:2940
1 lock held by syz.1.345/8302:
3 locks held by syz.2.346/8322:
5 locks held by syz.5.349/8327:
1 lock held by syz.9.347/8338:
2 locks held by syz-executor/8335:
1 lock held by sed/8337:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 37 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:161 [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:346 [inline]
watchdog+0xfd9/0x1030 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x51e/0xb90 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: 8337 Comm: sed Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:its_return_thunk+0x0/0x10 arch/x86/lib/retpoline.S:417
Code: cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 e9 2b 10 0b f6 cc
RSP: 0000:ffffc90006287758 EFLAGS: 00000293
RAX: ffffffff82320173 RBX: 000000000004b8f7 RCX: ffff888030463d00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: dffffc0000000000 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed10038a39a6 R12: 0000000000000001
R13: 000000000004b8f7 R14: dffffc0000000000 R15: ffff88801c51cd30
FS: 0000000000000000(0000) GS:ffff888126332000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4490307270 CR3: 000000006dbbe000 CR4: 00000000003526f0
Call Trace:
__page_table_check_zero+0x193/0x3e0 mm/page_table_check.c:139
page_table_check_alloc include/linux/page_table_check.h:38 [inline]
post_alloc_hook+0x240/0x280 mm/page_alloc.c:1890
prep_new_page mm/page_alloc.c:1897 [inline]
get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2490
folio_alloc_mpol_noprof mm/mempolicy.c:2509 [inline]
vma_alloc_folio_noprof+0xea/0x290 mm/mempolicy.c:2544
folio_prealloc mm/memory.c:-1 [inline]
do_cow_fault mm/memory.c:5823 [inline]
do_fault mm/memory.c:5935 [inline]
do_pte_missing+0x545/0x29e0 mm/memory.c:4477
handle_pte_fault mm/memory.c:6317 [inline]
__handle_mm_fault mm/memory.c:6455 [inline]
handle_mm_fault+0xd0a/0x13c0 mm/memory.c:6624
do_user_addr_fault+0xa73/0x1340 arch/x86/mm/fault.c:1334
handle_page_fault arch/x86/mm/fault.c:1474 [inline]
exc_page_fault+0x6a/0xc0 arch/x86/mm/fault.c:1527
asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f44902f061f
Code: 8d 0c 06 48 0f 44 c8 48 8b 05 f5 98 01 00 48 8b 78 08 48 01 cf 48 39 f9 72 1c eb 56 0f 1f 80 00 00 00 00 48 01 f0 48 83 c1 08 <48> 01 30 4c 8d 48 08 48 39 f9 73 35 48 8b 01 a8 01 74 e6 48 d1 e8
RSP: 002b:00007ffc24d6f390 EFLAGS: 00010216
RAX: 00007f4490307270 RBX: 0000000000000039 RCX: 00007f44902d4cc0
RDX: 0000000000000000 RSI: 00007f44902d4000 RDI: 00007f44902d4cd0
RBP: 00007ffc24d6f440 R08: 0000000000000000 R09: 0000000000000000
R10: 00007f4490308ef0 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000