syzbot

INFO: task syz-executor793:4166 blocked for more than 143 seconds.
      Not tainted 5.15.185-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor793 state:D stack:26048 pid: 4166 ppid:  4165 flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1e0 kernel/sched/core.c:6459
 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914
 gfs2_gl_hash_clear+0x1a4/0x2f0 fs/gfs2/glock.c:2183
 gfs2_put_super+0x769/0x7d0 fs/gfs2/super.c:624
 generic_shutdown_super+0x130/0x300 fs/super.c:475
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1139
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f99c762b5c7
RSP: 002b:00007ffd485a67e8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 000000000000cfef RCX: 00007f99c762b5c7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd485a68a0
RBP: 00007ffd485a68a0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000206 R12: 00007ffd485a7910
R13: 0000555584aca6c0 R14: 431bde82d7b634db R15: 00007ffd485a7930
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c11bfa0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
1 lock held by klogd/3536:
 #0: ffff8880b903a318 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x26/0x140 kernel/sched/core.c:475
2 locks held by getty/3935:
 #0: ffff88802b97a098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc900025d62e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158
1 lock held by syz-executor793/4166:
 #0: ffff888079a480e0 (&type->s_umount_key#43){++++}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.185-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:idle_cpu kernel/sched/core.c:7097 [inline]
RIP: 0010:nohz_csd_func+0x192/0x360 kernel/sched/core.c:1111
Code: 04 10 84 c0 0f 85 41 01 00 00 c6 03 00 48 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 49 81 c6 88 00 00 00 4c 89 f0 48 c1 e8 03 <0f> b6 04 10 84 c0 0f 85 57 01 00 00 45 8b 3e 45 85 ff 41 0f 94 c4
RSP: 0018:ffffc90000007f58 EFLAGS: 00000806
RAX: 1ffff11017207471 RBX: ffff8880b903a300 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff8880b903ad18
RBP: 0000000000000003 R08: dffffc0000000000 R09: ffffed1017207471
R10: ffffed1017207471 R11: 1ffff11017207470 R12: ffffffff8bebc3c0
R13: 0000000000000000 R14: ffff8880b903a388 R15: ffff8880b903a340
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005607f25f7168 CR3: 000000002a744000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 flush_smp_call_function_queue+0x505/0x760 kernel/smp.c:663
 __sysvec_call_function_single+0x98/0x240 arch/x86/kernel/smp.c:248
 instr_sysvec_call_function_single arch/x86/kernel/smp.c:243 [inline]
 sysvec_call_function_single+0x98/0xc0 arch/x86/kernel/smp.c:243
 </IRQ>
 <TASK>
 asm_sysvec_call_function_single+0x16/0x20 arch/x86/include/asm/idtentry.h:684
RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:723
Code: bf 48 89 df e8 26 8c 12 f8 eb b5 e8 3f be f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 97 13 5b 00 fb f4 <c3> 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48
RSP: 0018:ffffffff8be07dc8 EFLAGS: 000002c6
RAX: 6a36d67b0be89e00 RBX: ffffffff8bebc3c0 RCX: 6a36d67b0be89e00
RDX: 0000000000000001 RSI: ffffffff8a0b11c0 RDI: ffffffff8a59a740
RBP: ffffffff8be07ef8 R08: dffffc0000000000 R09: ffffed101720765a
R10: ffffed101720765a R11: 1ffff11017207659 R12: ffffffff8d68abe8
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff17d7878
 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112
 cpuidle_idle_call kernel/sched/idle.c:194 [inline]
 do_idle+0x21b/0x5b0 kernel/sched/idle.c:306
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403
 start_kernel+0x486/0x530 init/main.c:1140
 secondary_startup_64_no_verify+0xb1/0xbb
 </TASK>