INFO: task syz-executor:5839 blocked for more than 143 seconds.
Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor state:D stack:21640 pid:5839 tgid:5839 ppid:1 task_flags:0x400140 flags:0x00004004
Call Trace:
context_switch kernel/sched/core.c:5357 [inline]
__schedule+0x16f3/0x4c20 kernel/sched/core.c:6961
__schedule_loop kernel/sched/core.c:7043 [inline]
schedule+0x165/0x360 kernel/sched/core.c:7058
netfs_wait_for_outstanding_io include/linux/netfs.h:552 [inline]
v9fs_evict_inode+0x170/0x320 fs/9p/vfs_inode.c:348
evict+0x501/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:669
dput+0x19f/0x2b0 fs/dcache.c:911
shrink_dcache_for_umount+0xa0/0x170 fs/dcache.c:1621
generic_shutdown_super+0x67/0x2c0 fs/super.c:621
kill_anon_super+0x3b/0x70 fs/super.c:1282
v9fs_kill_super+0x4c/0x90 fs/9p/vfs_super.c:195
deactivate_locked_super+0xb9/0x130 fs/super.c:474
cleanup_mnt+0x425/0x4c0 fs/namespace.c:1375
task_work_run+0x1d4/0x260 kernel/task_work.c:227
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:43
exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
do_syscall_64+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa61fd3ff57
RSP: 002b:00007ffe19aa71d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fa61fdc1c2d RCX: 00007fa61fd3ff57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe19aa7290
RBP: 00007ffe19aa7290 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffe19aa8320
R13: 00007fa61fdc1c2d R14: 000000000006f1be R15: 00007ffe19aa8360
Showing all locks held in the system:
1 lock held by khungtaskd/38:
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8d9a8d80 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
1 lock held by jbd2/sda1-8/5166:
#0: ffff888033cb6108 (&journal->j_state_lock){++++}-{3:3}, at: write_lock include/linux/rwlock_rt.h:84 [inline]
#0: ffff888033cb6108 (&journal->j_state_lock){++++}-{3:3}, at: kjournald2+0x407/0x750 fs/jbd2/journal.c:231
2 locks held by getty/5594:
#0: ffff88823bf448a0 (&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+0x444/0x1410 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/5834:
1 lock held by syz-executor/5839:
#0: ffff88806cc340d0 (&type->s_umount_key#59){+.+.}-{4:4}, at: __super_lock fs/super.c:57 [inline]
#0: ffff88806cc340d0 (&type->s_umount_key#59){+.+.}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
#0: ffff88806cc340d0 (&type->s_umount_key#59){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0 fs/super.c:506
2 locks held by kworker/u8:15/6288:
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888019881138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc900061efbc0 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc900061efbc0 ((work_completion)(&sub_info->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
2 locks held by kworker/u8:32/6778:
#0: ffff888141389138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3211 [inline]
#0: ffff888141389138 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3319
#1: ffffc9000de8fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3212 [inline]
#1: ffffc9000de8fbc0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3319
6 locks held by kworker/u8:36/6783:
4 locks held by syz-executor/9670:
1 lock held by syz.1.1417/10612:
3 locks held by syz.2.1422/10638:
#0: ffff8880318656c8 (vm_lock){++++}-{0:0}, at: lock_vma_under_rcu+0x19f/0x3d0 mm/mmap_lock.c:147
#1: ffff888033cb0600 (sb_pagefaults){.+.+}-{0:0}, at: percpu_down_read_freezable include/linux/percpu-rwsem.h:83 [inline]
#1: ffff888033cb0600 (sb_pagefaults){.+.+}-{0:0}, at: __sb_start_write include/linux/fs.h:1799 [inline]
#1: ffff888033cb0600 (sb_pagefaults){.+.+}-{0:0}, at: sb_start_pagefault include/linux/fs.h:1964 [inline]
#1: ffff888033cb0600 (sb_pagefaults){.+.+}-{0:0}, at: ext4_page_mkwrite+0x1f7/0x1190 fs/ext4/inode.c:6703
#2: ffff888033cb6108 (&journal->j_state_lock){++++}-{3:3}, at: read_lock include/linux/rwlock_rt.h:37 [inline]
#2: ffff888033cb6108 (&journal->j_state_lock){++++}-{3:3}, at: start_this_handle+0x3a1/0x21c0 fs/jbd2/transaction.c:364
7 locks held by syz.0.1423/10640:
2 locks held by modprobe/10642:
=============================================
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 08/18/2025
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:160 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:328 [inline]
watchdog+0xf93/0xfe0 kernel/hung_task.c:491
kthread+0x70e/0x8a0 kernel/kthread.c:463
ret_from_fork+0x436/0x7d0 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: 10643 Comm: syz.2.1422 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
RIP: 0010:check_preemption_disabled+0x1/0x120 lib/smp_processor_id.c:13
Code: 20 16 62 8b 48 c7 c6 60 16 62 8b eb 1c 66 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 55 <41> 57 41 56 53 48 83 ec 10 65 48 8b 05 fe 24 ff 06 48 89 44 24 08
RSP: 0018:ffffc9000d56f4d0 EFLAGS: 00000092
RAX: 0000000000000001 RBX: 0000000000000000 RCX: c38b0a66512e7900
RDX: 0000000000000000 RSI: ffffffff8d21ae96 RDI: ffffffff8b621680
RBP: ffffffff8af9484a R08: 0000000000000000 R09: ffffffff8af9484a
R10: dffffc0000000000 R11: fffffbfff1e3ac27 R12: 0000000000000000
R13: ffff88806d63df98 R14: 0000000000000001 R15: 0000000000000046
FS: 00007fb2f1d4d6c0(0000) GS:ffff8881268bc000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb2f1d4dd58 CR3: 00000000293f0000 CR4: 00000000003526f0
Call Trace:
lockdep_recursion_finish kernel/locking/lockdep.c:470 [inline]
lock_acquire+0x130/0x360 kernel/locking/lockdep.c:5870
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0xa7/0xf0 kernel/locking/spinlock.c:162
rt_mutex_slowunlock+0xaa/0x2e0 kernel/locking/rtmutex.c:1417
__unix_dgram_recvmsg+0xa03/0xd60 net/unix/af_unix.c:2684
sock_recvmsg_nosec+0x186/0x1c0 net/socket.c:1065
____sys_recvmsg+0x3ab/0x470 net/socket.c:2832
___sys_recvmsg+0x1b5/0x510 net/socket.c:2876
do_recvmmsg+0x30d/0x770 net/socket.c:2971
__sys_recvmmsg net/socket.c:3045 [inline]
__do_sys_recvmmsg net/socket.c:3068 [inline]
__se_sys_recvmmsg net/socket.c:3061 [inline]
__x64_sys_recvmmsg+0x190/0x240 net/socket.c:3061
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: 0033:0x7fb2f3b0ec29
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fb2f1d4d038 EFLAGS: 00000246 ORIG_RAX: 000000000000012b
RAX: ffffffffffffffda RBX: 00007fb2f3d56090 RCX: 00007fb2f3b0ec29
RDX: 0000000000010106 RSI: 00002000000000c0 RDI: 0000000000000003
RBP: 00007fb2f3b91e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000002 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb2f3d56128 R14: 00007fb2f3d56090 R15: 00007ffc04deaf58