INFO: task syz.9.190:7675 blocked for more than 143 seconds.
Not tainted 6.15.0-syzkaller-13473-gc0c9379f235d #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.9.190 state:D stack:25064 pid:7675 tgid:7671 ppid:7147 task_flags:0x400140 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_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:912 [inline]
filename_create+0x1f9/0x470 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: 0033:0x7f387598e929
RSP: 002b:00007f387686a038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007f3875bb6080 RCX: 00007f387598e929
RDX: 0000000000000000 RSI: 0000200000002040 RDI: ffffffffffffff9c
RBP: 00007f3875a10b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f3875bb6080 R15: 00007ffcdc996968
Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
4 locks held by kworker/u8:1/13:
#0: ffff88814368b148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814368b148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000127bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88802a1dc0e0 (&type->s_umount_key#112){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff888059103918 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
1 lock held by khungtaskd/31:
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13f060 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:7/1325:
2 locks held by getty/5590:
#0: ffff88814da880a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc900036bb2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by udevd/6685:
4 locks held by syz.9.190/7672:
2 locks held by syz.9.190/7675:
#0: ffff88802a1dc428 (sb_writers#31){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff888059103cc8 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:912 [inline]
#1: ffff888059103cc8 (&type->i_mutex_dir_key#21/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4139
2 locks held by syz.6.225/8036:
#0: ffff88802a1dc0e0 (&type->s_umount_key#112){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88802a1dc0e0 (&type->s_umount_key#112){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff8880250447d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff8880250447d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
2 locks held by syz.4.436/9996:
1 lock held by syz.3.437/10016:
#0: ffffffff8e144b78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144b78 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
2 locks held by syz.8.439/10030:
2 locks held by dhcpcd-run-hook/10052:
#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
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-syzkaller-13473-gc0c9379f235d #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+0x3f9/0x770 arch/x86/kernel/process.c:148
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: 10030 Comm: syz.8.439 Not tainted 6.15.0-syzkaller-13473-gc0c9379f235d #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:841 [inline]
RIP: 0010:class_rcu_constructor include/linux/rcupdate.h:1155 [inline]
RIP: 0010:unwind_next_frame+0x9e/0x2390 arch/x86/kernel/unwind_orc.c:479
Code: b6 04 2c 84 c0 0f 85 de 1b 00 00 41 8b 06 85 c0 0f 84 32 02 00 00 89 84 24 84 00 00 00 4c 89 bc 24 90 00 00 00 e8 c2 3c 35 00 <4c> 8d 3d 00 00 00 00 48 c7 c7 60 f0 13 8e 31 f6 31 d2 b9 02 00 00
RSP: 0018:ffffc90004b1f038 EFLAGS: 00000283
RAX: 0000000000000001 RBX: ffffffff81ace52c RCX: dffffc0000000000
RDX: dffffc0000000000 RSI: ffffffff81ace52c RDI: ffffc90004b1f108
RBP: dffffc0000000000 R08: ffffc90004b1f1d0 R09: 0000000000000000
R10: ffffc90004b1f158 R11: ffffffff81ace580 R12: 1ffff92000963e21
R13: ffffc90004b1f140 R14: ffffc90004b1f108 R15: ffffc90004b1f1a0
FS: 00007fe6a99f66c0(0000) GS:ffff888125c87000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f635dfa6438 CR3: 000000004181a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
save_stack+0xf7/0x1f0 mm/page_owner.c:156
__set_page_owner+0x8d/0x4a0 mm/page_owner.c:329
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1704
prep_new_page mm/page_alloc.c:1712 [inline]
get_page_from_freelist+0x21d5/0x22b0 mm/page_alloc.c:3669
__alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4959
alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2419
folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2438
shmem_alloc_folio mm/shmem.c:1851 [inline]
shmem_alloc_and_add_folio+0x447/0xf60 mm/shmem.c:1890
shmem_get_folio_gfp+0x59d/0x1660 mm/shmem.c:2532
shmem_get_folio mm/shmem.c:2638 [inline]
shmem_write_begin+0xf7/0x2b0 mm/shmem.c:3288
generic_perform_write+0x2c4/0x910 mm/filemap.c:4112
shmem_file_write_iter+0xf8/0x120 mm/shmem.c:3463
new_sync_write fs/read_write.c:593 [inline]
vfs_write+0x54b/0xa90 fs/read_write.c:686
ksys_write+0x145/0x250 fs/read_write.c:738
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: 0033:0x7fe6abb8d3df
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007fe6a99f5df0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000001000000 RCX: 00007fe6abb8d3df
RDX: 0000000001000000 RSI: 00007fe6a1400000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 00000000000050ed
R10: 000020000000a2c2 R11: 0000000000000293 R12: 0000000000000004
R13: 00007fe6a99f5ef0 R14: 00007fe6a99f5eb0 R15: 00007fe6a1400000