INFO: task syz.6.217:7486 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.6.217 state:D stack:24728 pid:7486 tgid:7484 ppid:6335 task_flags:0x400140 flags:0x00080002
Call Trace:
context_switch kernel/sched/core.c:5295 [inline]
__schedule+0x14de/0x5210 kernel/sched/core.c:6907
__schedule_loop kernel/sched/core.c:6989 [inline]
schedule+0x164/0x360 kernel/sched/core.c:7004
io_schedule+0x80/0xe0 kernel/sched/core.c:7831
folio_wait_bit_common+0x6dd/0xbc0 mm/filemap.c:1323
folio_lock include/linux/pagemap.h:1170 [inline]
release_metapage+0x103/0xab0 fs/jfs/jfs_metapage.c:870
discard_metapage fs/jfs/jfs_metapage.h:88 [inline]
__get_metapage+0x9a3/0xde0 fs/jfs/jfs_metapage.c:753
dtSplitPage+0x791/0x37c0 fs/jfs/jfs_dtree.c:1471
dtSplitUp fs/jfs/jfs_dtree.c:1092 [inline]
dtInsert+0x10a4/0x5f10 fs/jfs/jfs_dtree.c:871
jfs_mkdir+0x783/0xb00 fs/jfs/namei.c:271
vfs_mkdir+0x40b/0x630 fs/namei.c:5233
filename_mkdirat+0x289/0x520 fs/namei.c:5266
__do_sys_mkdirat fs/namei.c:5287 [inline]
__se_sys_mkdirat+0x35/0x150 fs/namei.c:5284
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: 0033:0x7f4823feb507
RSP: 002b:00007f482223de58 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f482223dee0 RCX: 00007f4823feb507
RDX: 00000000000001ff RSI: 0000200000000800 RDI: 00000000ffffff9c
RBP: 0000000000000000 R08: 0000200000000040 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000800
R13: 00007f482223dea0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
4 locks held by kworker/u8:1/13:
#0: ffff88801aaec138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3250 [inline]
#0: ffff88801aaec138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9d4/0x17a0 kernel/workqueue.c:3358
#1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3251 [inline]
#1: ffffc90000127c40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa0f/0x17a0 kernel/workqueue.c:3358
#2: ffff88805e0ec0d0 (&type->s_umount_key#61){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565
#3: ffff88806049d9a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108
4 locks held by pr/legacy/17:
1 lock held by khungtaskd/38:
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
#0: ffffffff8dbcd480 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:3/58:
4 locks held by kworker/1:2/807:
2 locks held by udevd/5163:
#0: ffff888037cba480 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88803b1ca498 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff88803b1ca498 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline]
#1: ffff88803b1ca498 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline]
#1: ffff88803b1ca498 (&type->i_mutex_dir_key#5/1){+.+.}-{4:4}, at: filename_unlinkat+0x2ad/0x610 fs/namei.c:5521
2 locks held by getty/5555:
#0: ffff888036ec60a0 (&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+0x462/0x13c0 drivers/tty/n_tty.c:2211
4 locks held by syz.6.217/7486:
#0: ffff88805e0ec480 (sb_writers#12){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:493
#1: ffff88806049dd78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:1073 [inline]
#1: ffff88806049dd78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: __start_dirop fs/namei.c:2923 [inline]
#1: ffff88806049dd78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: start_dirop fs/namei.c:2934 [inline]
#1: ffff88806049dd78 (&type->i_mutex_dir_key#8/1){+.+.}-{4:4}, at: filename_create+0x200/0x370 fs/namei.c:4922
#2: ffff88806049d9a8 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_mkdir+0x235/0xb00 fs/jfs/namei.c:234
#3: ffff88806049a8e8 (&jfs_ip->commit_mutex/1){+.+.}-{4:4}, at: jfs_mkdir+0x250/0xb00 fs/jfs/namei.c:235
2 locks held by syz.7.336/8606:
#0: ffff88805e0ec0d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88805e0ec0d0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff88802540a8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff88802540a8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2922
2 locks held by syz.7.336/8633:
#0: ffff88805e0ec0d0 (&type->s_umount_key#61){++++}-{4:4}, at: __super_lock fs/super.c:60 [inline]
#0: ffff88805e0ec0d0 (&type->s_umount_key#61){++++}-{4:4}, at: super_lock+0x2d6/0x3d0 fs/super.c:122
#1: ffff88802540a8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:397 [inline]
#1: ffff88802540a8c0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x1c5/0xc10 fs/fs-writeback.c:2922
1 lock held by syz-executor/8767:
2 locks held by udevd/8987:
2 locks held by udevd/9171:
1 lock held by syz.3.376/9236:
1 lock held by syz.4.377/9250:
#0: ffff88803bdae0d0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x28c/0xac0 fs/super.c:345
2 locks held by syz.5.378/9262:
2 locks held by syz.5.378/9266:
#0: ffff88803fba2480 (sb_writers#22){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2710 [inline]
#0: ffff88803fba2480 (sb_writers#22){.+.+}-{0:0}, at: vfs_fallocate+0x5f9/0x7f0 fs/open.c:339
#1: ffff8880604431c8 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:1028 [inline]
#1: ffff8880604431c8 (&sb->s_type->i_mutex_key#40){+.+.}-{4:4}, at: ntfs_fallocate+0x2f1/0x1140 fs/ntfs3/file.c:606
2 locks held by syz.1.379/9265:
4 locks held by dhcpcd-run-hook/9267:
#0: ffffffff8dc99d30 (dup_mmap_sem){.+.+}-{0:0}, at: dup_mm kernel/fork.c:1529 [inline]
#0: ffffffff8dc99d30 (dup_mmap_sem){.+.+}-{0:0}, at: copy_mm+0x130/0x4b0 kernel/fork.c:1582
#1: ffff888019fe5cf0 (&mm->mmap_lock){++++}-{4:4}, at: mmap_write_lock_killable include/linux/mmap_lock.h:353 [inline]
#1: ffff888019fe5cf0 (&mm->mmap_lock){++++}-{4:4}, at: dup_mmap+0x153/0x1b70 mm/mmap.c:1726
#2: ffff888038b736b0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: mmap_write_lock_nested include/linux/mmap_lock.h:343 [inline]
#2: ffff888038b736b0 (&mm->mmap_lock/1){+.+.}-{4:4}, at: dup_mmap+0x233/0x1b70 mm/mmap.c:1733
#3: ffff8880b8942250 ((&pcs->lock)){+.+.}-{3:3}, at: spin_lock include/linux/spinlock_rt.h:45 [inline]
#3: ffff8880b8942250 ((&pcs->lock)){+.+.}-{3:3}, at: kmem_cache_prefill_sheaf+0xbd/0x540 mm/slub.c:4912
=============================================
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 02/12/2026
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+0xf90/0xfe0 kernel/hung_task.c:515
kthread+0x388/0x470 kernel/kthread.c:467
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: 17 Comm: pr/legacy Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
RIP: 0010:io_serial_in+0x77/0xc0 drivers/tty/serial/8250/8250_port.c:400
Code: e8 4e 38 9d fc 44 89 f9 d3 e3 49 83 ee 80 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 9f 51 02 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900001679d0 EFLAGS: 00000202
RAX: 1ffffffff32df200 RBX: 00000000000003fd RCX: 0000000000000000
RDX: 00000000000003fd RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffffff996f9930 R08: 0000000000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: ffffffff8525dce0 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffffff996f96a0 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff888126595000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f327a385800 CR3: 0000000038586000 CR4: 00000000003526f0
Call Trace:
serial_in drivers/tty/serial/8250/8250.h:128 [inline]
serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline]
wait_for_lsr+0x1aa/0x2f0 drivers/tty/serial/8250/8250_port.c:1961
fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline]
serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline]
serial8250_console_write+0x120d/0x1b90 drivers/tty/serial/8250/8250_port.c:3342
console_emit_next_record kernel/printk/printk.c:3111 [inline]
console_flush_one_record+0x68b/0xb90 kernel/printk/printk.c:3217
legacy_kthread_func+0x1b6/0x250 kernel/printk/printk.c:3676
kthread+0x388/0x470 kernel/kthread.c:467
ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245