INFO: task syz.4.64:6251 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.64 state:D stack:28240 pid:6251 tgid:6228 ppid:5800 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_nested include/linux/fs.h:1073 [inline]
__start_dirop fs/namei.c:2929 [inline]
start_dirop fs/namei.c:2940 [inline]
filename_create+0x200/0x370 fs/namei.c:4928
filename_symlinkat+0xf7/0x420 fs/namei.c:5640
__do_sys_symlinkat fs/namei.c:5666 [inline]
__se_sys_symlinkat+0x4e/0x2b0 fs/namei.c:5661
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: 0033:0x7f708c9fc819
RSP: 002b:00007f708ac2d028 EFLAGS: 00000246 ORIG_RAX: 000000000000010a
RAX: ffffffffffffffda RBX: 00007f708cc76090 RCX: 00007f708c9fc819
RDX: 0000200000000000 RSI: ffffffffffffff9c RDI: 0000200000002040
RBP: 00007f708ca92c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f708cc76128 R14: 00007f708cc76090 R15: 00007ffd93035fa8
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#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 kworker/u8:4/68:
2 locks held by kworker/u8:4/68:
4 locks held by kworker/u8:7/819:
#0: ffff88801aac4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3263 [inline]
#0: ffff88801aac4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa52/0x18c0 kernel/workqueue.c:3371
#1: ffffc90004a67c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3264 [inline]
#1: ffffc90004a67c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa8d/0x18c0 kernel/workqueue.c:3371
#2: ffff88803143c0d0 (&type->s_umount_key#61){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff888062a3cfe8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
1 lock held by udevd/5164:
2 locks held by getty/5554:
#0: ffff8880369270a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
2 locks held by udevd/5814:
1 lock held by udevd/6132:
#0: ffff88802273a3b0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:1043 [inline]
#0: ffff88802273a3b0 (&sb->s_type->i_mutex_key#9){++++}-{4:4}, at: blkdev_read_iter+0x2ff/0x440 block/fops.c:854
4 locks held by syz.4.64/6229:
2 locks held by syz.4.64/6251:
#0: ffff88803143c480 (sb_writers#16){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff888062a3d3b8 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff888062a3d3b8 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2929 [inline]
#1: ffff888062a3d3b8 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2940 [inline]
#1: ffff888062a3d3b8 (&type->i_mutex_dir_key#11/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4928
1 lock held by syz-executor/7446:
1 lock held by syz-executor/7902:
2 locks held by syz.7.319/8243:
2 locks held by syz.2.320/8247:
1 lock held by syz.6.321/8251:
1 lock held by dhcpcd-run-hook/8254:
#0: ffff88803dc9a8d8 (&pipe->rd_wait){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#0: ffff88803dc9a8d8 (&pipe->rd_wait){+.+.}-{3:3}, at: finish_wait+0xbe/0x1e0 kernel/sched/wait.c:394
3 locks held by dhcpcd-run-hook/8256:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 38 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 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8251 Comm: syz.6.321 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:26 [inline]
RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:109 [inline]
RIP: 0010:check_preemption_disabled+0x29/0xe0 lib/smp_processor_id.c:19
Code: 90 55 41 57 41 56 53 65 8b 05 47 73 2a 07 65 8b 0d 3c 73 2a 07 f7 c1 ff ff ff 7f 74 0c 5b 41 5e 41 5f 5d e9 99 a5 03 00 cc 9c <59> f7 c1 00 02 00 00 74 ea 65 4c 8b 3d ee 72 2a 07 41 f6 47 2f 04
RSP: 0018:ffffc900056af2b8 EFLAGS: 00000046
RAX: 0000000000000001 RBX: 0000000000000202 RCX: 0000000080000000
RDX: 0000000000000000 RSI: ffffffff8d57ea61 RDI: ffffffff8ba67a80
RBP: ffff88801ca10ca0 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffed1003942194 R12: 00000000000569c1
R13: ffffffff82320994 R14: ffffffff8ddcb980 R15: ffff888034130000
FS: 0000000000000000(0000) GS:ffff888126432000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007feedaab1000 CR3: 000000003d7f6000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_inc kernel/locking/lockdep.c:465 [inline]
lock_release+0xa1/0x3d0 kernel/locking/lockdep.c:5888
rcu_lock_release include/linux/rcupdate.h:322 [inline]
rcu_read_unlock include/linux/rcupdate.h:881 [inline]
page_table_check_clear+0x4b8/0x5f0 mm/page_table_check.c:89
ptep_get_and_clear_full arch/x86/include/asm/jump_label.h:-1 [inline]
get_and_clear_full_ptes include/linux/pgtable.h:846 [inline]
zap_present_folio_ptes mm/memory.c:1643 [inline]
zap_present_ptes mm/memory.c:1725 [inline]
do_zap_pte_range mm/memory.c:1827 [inline]
zap_pte_range mm/memory.c:1929 [inline]
zap_pmd_range mm/memory.c:2021 [inline]
zap_pud_range mm/memory.c:2049 [inline]
zap_p4d_range mm/memory.c:2070 [inline]
unmap_page_range+0x3015/0x4540 mm/memory.c:2091
unmap_single_vma mm/memory.c:2133 [inline]
unmap_vmas+0x48f/0x6a0 mm/memory.c:2171
exit_mmap+0x280/0xa10 mm/mmap.c:1302
__mmput+0xcb/0x3d0 kernel/fork.c:1175
exit_mm+0x168/0x220 kernel/exit.c:581
do_exit+0x6a2/0x23c0 kernel/exit.c:964
do_group_exit+0x21b/0x2d0 kernel/exit.c:1118
get_signal+0x125c/0x1310 kernel/signal.c:3034
arch_do_signal_or_restart+0xbc/0x830 arch/x86/kernel/signal.c:337
__exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
exit_to_user_mode_loop+0x86/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa4aa69c819
Code: Unable to access opcode bytes at 0x7fa4aa69c7ef.
RSP: 002b:00007fa4a88f60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007fa4aa915fa8 RCX: 00007fa4aa69c819
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fa4aa915fa8
RBP: 00007fa4aa915fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa4aa916038 R14: 00007fffedff2970 R15: 00007fffedff2a58