INFO: task syz.0.196:7574 blocked for more than 143 seconds.
Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.196 state:D
stack:28744 pid:7574 tgid:7561 ppid:5832 task_flags:0x400040 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5396 [inline]
__schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
__schedule_loop kernel/sched/core.c:6863 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6878
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write+0x1ab/0x1f0 kernel/locking/rwsem.c:1578
inode_lock include/linux/fs.h:867 [inline]
open_last_lookups fs/namei.c:3804 [inline]
path_openat+0x8da/0x3830 fs/namei.c:4043
do_filp_open+0x1fa/0x410 fs/namei.c:4073
do_sys_openat2+0x121/0x1c0 fs/open.c:1437
do_sys_open fs/open.c:1452 [inline]
__do_sys_openat fs/open.c:1468 [inline]
__se_sys_openat fs/open.c:1463 [inline]
__x64_sys_openat+0x138/0x170 fs/open.c:1463
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: 0033:0x7f649e98e929
RSP: 002b:00007f649f87b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f649ebb6080 RCX: 00007f649e98e929
RDX: 000000000000275a RSI: 0000200000000000 RDI: ffffffffffffff9c
RBP: 00007f649ea10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f649ebb6080 R15: 00007ffccaa854a8
Showing all locks held in the system:
2 locks held by kworker/u8:1/13:
#0: ffff8880b873b798 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
#1: ffff8880b8723f08 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x39e/0x6d0 kernel/sched/psi.c:987
1 lock held by khungtaskd/31:
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13eda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:3/50:
#0: ffff8880206a3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff8880206a3148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000bb7bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff888031f000e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888068239d70 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
2 locks held by getty/5583:
#0: ffff888030e4b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900033332f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/5823:
4 locks held by syz.0.196/7564:
2 locks held by syz.0.196/7574:
#0: ffff888031f00428 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88806823a120 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: inode_lock include/linux/fs.h:867 [inline]
#1: ffff88806823a120 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: open_last_lookups fs/namei.c:3804 [inline]
#1: ffff88806823a120 (&type->i_mutex_dir_key#9){++++}-{4:4}, at: path_openat+0x8da/0x3830 fs/namei.c:4043
2 locks held by syz.6.294/8576:
#0: ffff888031f000e0 (&type->s_umount_key#58){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff888031f000e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff8881413c87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8881413c87d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:470
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 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: 9909 Comm: ext4lazyinit Not tainted 6.16.0-rc1-syzkaller-00010-g2c4a1f3fe03e #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__bfs kernel/locking/lockdep.c:1818 [inline]
RIP: 0010:__bfs_backwards kernel/locking/lockdep.c:1863 [inline]
RIP: 0010:check_irq_usage kernel/locking/lockdep.c:2799 [inline]
RIP: 0010:check_prev_add kernel/locking/lockdep.c:3172 [inline]
RIP: 0010:check_prevs_add kernel/locking/lockdep.c:3287 [inline]
RIP: 0010:validate_chain+0xfd7/0x2140 kernel/locking/lockdep.c:3911
Code: 25 ff 0f 00 00 39 05 c4 ed 02 12 73 06 89 05 bc ed 02 12 49 8b 04 24 48 89 de 48 39 e8 0f 84 33 fe ff ff 4c 89 68 30 48 8b 00 <48> 39 e8 75 f4 48 89 de e9 1f fe ff ff 48 c7 c7 b0 fc 00 8e 48 89
RSP: 0018:ffffc9000e206eb8 EFLAGS: 00000002
RAX: ffffffff96260248 RBX: 00000000000003fd RCX: 00000000000000e2
RDX: 0000000000000008 RSI: 00000000000003fd RDI: ffff88802f25da00
RBP: ffffffff9342e448 R08: ffffc9000e206e80 R09: 0000000000000020
R10: ffffc9000e2071c0 R11: ffffffff819e9520 R12: ffffffff96254cb8
R13: ffffffff9644ed88 R14: ffff88802f25e5b8 R15: 00000000000000e1
FS: 0000000000000000(0000) GS:ffff888125d86000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffead497ff8 CR3: 0000000033fd0000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__lock_acquire+0xab9/0xd20 kernel/locking/lockdep.c:5240
lock_acquire+0x120/0x360 kernel/locking/lockdep.c:5871
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
debug_object_activate+0xbb/0x420 lib/debugobjects.c:818
debug_work_activate kernel/workqueue.c:664 [inline]
insert_work+0x35/0x330 kernel/workqueue.c:2180
__queue_work+0xcfc/0xfe0 kernel/workqueue.c:2341
mod_delayed_work_on+0xf8/0x200 kernel/workqueue.c:2597
kblockd_mod_delayed_work_on+0x29/0x40 block/blk-core.c:1115
blk_mq_dispatch_list+0xd0c/0xe00 include/linux/spinlock.h:-1
blk_mq_flush_plug_list+0x469/0x550 block/blk-mq.c:2965
__blk_flush_plug+0x3d3/0x4b0 block/blk-core.c:1220
blk_flush_plug include/linux/blkdev.h:1118 [inline]
io_schedule_prepare kernel/sched/core.c:7692 [inline]
io_schedule_timeout+0x7f/0xf0 kernel/sched/core.c:7710
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common kernel/sched/completion.c:116 [inline]
wait_for_common_io+0x2ca/0x600 kernel/sched/completion.c:133
blk_wait_io block/blk.h:91 [inline]
submit_bio_wait+0x147/0x200 block/bio.c:1362
blkdev_issue_write_zeroes block/blk-lib.c:166 [inline]
blkdev_issue_zeroout+0x461/0x7c0 block/blk-lib.c:319
sb_issue_zeroout include/linux/blkdev.h:1203 [inline]
ext4_init_inode_table+0x474/0x8d0 fs/ext4/ialloc.c:1600
ext4_run_li_request fs/ext4/super.c:3716 [inline]
ext4_lazyinit_thread+0x6e1/0x1880 fs/ext4/super.c:3811
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245