INFO: task syz.3.1628:19143 blocked for more than 143 seconds.
Not tainted 6.16.0-rc4-syzkaller-00108-g17bbde2e1716 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.1628 state:D stack:28904 pid:19143 tgid:19102 ppid:16255 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_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:914 [inline]
filename_create+0x1f9/0x470 fs/namei.c:4148
do_mkdirat+0xa0/0x590 fs/namei.c:4400
__do_sys_mkdirat fs/namei.c:4425 [inline]
__se_sys_mkdirat fs/namei.c:4423 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4423
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: 0033:0x7fe831d8d197
RSP: 002b:00007fe832b68e68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fe832b68ef0 RCX: 00007fe831d8d197
RDX: 00000000000001ff RSI: 0000200000000680 RDI: 00000000ffffff9c
RBP: 0000200000000080 R08: 0000200000000140 R09: 0000000000000000
R10: 0000200000000080 R11: 0000000000000246 R12: 0000200000000680
R13: 00007fe832b68eb0 R14: 0000000000000000 R15: 0000000000000000
Showing all locks held in the system:
1 lock held by khungtaskd/31:
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8e13ee20 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
3 locks held by kworker/u8:3/37:
#0: ffff88814c067948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814c067948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90000ad7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90000ad7bc0 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffffffff8f4fd948 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f4fd948 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
4 locks held by kworker/u8:7/1151:
#0: ffff88801e6fa948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801e6fa948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
#1: ffffc90003abfbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90003abfbc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
#2: ffff88807d37e0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
#3: ffff88804d9ec250 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
2 locks held by getty/5584:
#0: ffff88814c4540a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
4 locks held by syz.3.1628/19142:
2 locks held by syz.3.1628/19143:
#0: ffff88807d37e428 (sb_writers#13){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
#1: ffff88804d9ec600 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:914 [inline]
#1: ffff88804d9ec600 (&type->i_mutex_dir_key#10/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4148
2 locks held by syz.9.1708/19789:
#0: ffff88807d37e0e0 (&type->s_umount_key#57){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
#0: ffff88807d37e0e0 (&type->s_umount_key#57){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
#1: ffff888142f7c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
#1: ffff888142f7c7d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
1 lock held by syz-executor/20056:
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
#0: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
3 locks held by syz-executor/20940:
#0: ffffffff8f4fd948 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
#0: ffffffff8f4fd948 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
#0: ffffffff8f4fd948 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
#1: ffff888024d394e8 (&wg->device_update_lock){+.+.}-{4:4}, at: wg_open+0x227/0x420 drivers/net/wireguard/device.c:50
#2: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#2: ffffffff8e144938 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f6/0x730 kernel/rcu/tree_exp.h:998
1 lock held by syz.8.1864/21325:
#0: ffff88802c0c80e0 (&type->s_umount_key#55/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
1 lock held by dhcpcd/21347:
#0: ffff88801190e208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: inode_lock include/linux/fs.h:869 [inline]
#0: ffff88801190e208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: __sock_release net/socket.c:646 [inline]
#0: ffff88801190e208 (&sb->s_type->i_mutex_key#10){+.+.}-{4:4}, at: sock_close+0x9b/0x240 net/socket.c:1391
1 lock held by sed/21356:
=============================================
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00108-g17bbde2e1716 #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+0x711/0x8a0 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 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 15619 Comm: udevd Not tainted 6.16.0-rc4-syzkaller-00108-g17bbde2e1716 #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:__sanitizer_cov_trace_const_cmp1+0x0/0x90 kernel/kcov.c:299
Code: 89 74 0a 18 48 89 44 0a 20 c3 cc cc cc cc cc 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 8b 04 24 65 48 8b 14 25 08 c0 99 92 65 8b 0d 88 6f
RSP: 0018:ffffc9000425f5e8 EFLAGS: 00000246
RAX: 0000000000000001 RBX: ffffffff81f792fc RCX: 0000000000000002
RDX: ffff8880260c8000 RSI: 0000000000000001 RDI: 0000000000000002
RBP: 0000000000000001 R08: ffffea0000ced037 R09: 1ffffd400019da06
R10: dffffc0000000000 R11: fffff9400019da07 R12: dffffc0000000000
R13: ffffea0000ced000 R14: ffffea0000ced034 R15: 0000000000000001
FS: 00007f371e342880(0000) GS:ffff888125c84000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f371dbfa000 CR3: 000000006cc2c000 CR4: 00000000003526f0
Call Trace:
arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline]
raw_atomic_try_cmpxchg include/linux/atomic/atomic-arch-fallback.h:2130 [inline]
raw_atomic_fetch_add_unless include/linux/atomic/atomic-arch-fallback.h:2431 [inline]
raw_atomic_add_unless include/linux/atomic/atomic-arch-fallback.h:2456 [inline]
atomic_add_unless include/linux/atomic/atomic-instrumented.h:1518 [inline]
page_ref_add_unless include/linux/page_ref.h:238 [inline]
folio_ref_add_unless include/linux/page_ref.h:248 [inline]
folio_try_get+0x12a/0x340 include/linux/page_ref.h:264
filemap_get_read_batch+0x22c/0x7b0 mm/filemap.c:2380
filemap_get_pages+0x2eb/0x1ea0 mm/filemap.c:2592
filemap_read+0x3f6/0x11a0 mm/filemap.c:2711
blkdev_read_iter+0x30a/0x440 block/fops.c:833
new_sync_read fs/read_write.c:491 [inline]
vfs_read+0x4cd/0x980 fs/read_write.c:572
ksys_read+0x145/0x250 fs/read_write.c:715
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: 0033:0x7f371dca7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff3b4c6f30 EFLAGS: 00000202 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 00007f371e342880 RCX: 00007f371dca7407
RDX: 0000000000000200 RSI: 00007f371dbf9000 RDI: 0000000000000009
RBP: 00005624b3ff1ee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000001fb6200 R14: 00005624b3fe9748 R15: 00007f371e46939c