INFO: task syz.7.718:8994 blocked for more than 143 seconds.
      Not tainted 6.13.0-rc3-next-20241220-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.718       state:D stack:27328 pid:8994  tgid:8978  ppid:8264   flags:0x00000004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5371 [inline]
 __schedule+0x189f/0x4c80 kernel/sched/core.c:6758
 __schedule_loop kernel/sched/core.c:6835 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6850
 d_wait_lookup fs/dcache.c:2477 [inline]
 d_alloc_parallel+0xc16/0x1600 fs/dcache.c:2559
 __lookup_slow+0x117/0x3f0 fs/namei.c:1776
 lookup_slow+0x53/0x70 fs/namei.c:1808
 walk_component fs/namei.c:2112 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2477
 path_lookupat+0xa9/0x450 fs/namei.c:2633
 filename_lookup+0x2a3/0x670 fs/namei.c:2663
 user_path_at+0x3a/0x60 fs/namei.c:3070
 do_mount fs/namespace.c:3893 [inline]
 __do_sys_mount fs/namespace.c:4107 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:4084
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb418185d29
RSP: 002b:00007fb418f6d038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb418376160 RCX: 00007fb418185d29
RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000000
RBP: 00007fb418201aa8 R08: 0000000020000140 R09: 0000000000000000
R10: 0000000000000020 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007fb418376160 R15: 00007ffd342c0328
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
 #0: ffffffff8e937da0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6744
2 locks held by kworker/u8:3/53:
 #0: ffff8880b863e998 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598
 #1: ffff8880b8628948 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x41d/0x7a0 kernel/sched/psi.c:987
2 locks held by getty/5583:
 #0: ffff8880310df0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x6a6/0x1e00 drivers/tty/n_tty.c:2211
1 lock held by syz.7.718/8985:
1 lock held by syz.7.718/8994:
 #0: ffff88807a784c00 (&type->i_mutex_dir_key#22){.+.+}-{4:4}, at: inode_lock_shared include/linux/fs.h:873 [inline]
 #0: ffff88807a784c00 (&type->i_mutex_dir_key#22){.+.+}-{4:4}, at: lookup_slow+0x45/0x70 fs/namei.c:1807
1 lock held by syz-executor/9115:
 #0: ffffffff8e93d278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:334 [inline]
 #0: ffffffff8e93d278 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x451/0x830 kernel/rcu/tree_exp.h:996

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc3-next-20241220-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline]
 watchdog+0xff6/0x1040 kernel/hung_task.c:397
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 8985 Comm: syz.7.718 Not tainted 6.13.0-rc3-next-20241220-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:check_preemption_disabled+0x4f/0x120 lib/smp_processor_id.c:55
Code: 11 74 a9 ff ff ff 7f 74 26 65 48 8b 04 25 28 00 00 00 48 3b 44 24 08 0f 85 ce 00 00 00 89 d8 48 83 c4 10 5b 41 5c 41 5e 41 5f <c3> cc cc cc cc 48 c7 04 24 00 00 00 00 9c 8f 04 24 f7 04 24 00 02
RSP: 0018:ffffc90002707078 EFLAGS: 00000082
RAX: 0000000000000001 RBX: 0000000000000200 RCX: ffffffff81c6e42c
RDX: 0000000000000000 RSI: ffffffff8c5fece0 RDI: ffffffff8c5feca0
RBP: ffffc900027071c0 R08: ffffffff901ab1f7 R09: 1ffffffff203563e
R10: dffffc0000000000 R11: fffffbfff203563f R12: 0000000000000246
R13: dffffc0000000000 R14: 0000000000000400 R15: 00000000003186d1
FS:  00007fb418f8e6c0(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d6a9452d8 CR3: 000000003541c000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lookup_bh_lru fs/buffer.c:1360 [inline]
 __find_get_block+0x195/0x1140 fs/buffer.c:1394
 __getblk_slow fs/buffer.c:1127 [inline]
 bdev_getblk+0x189/0x670 fs/buffer.c:1431
 __bread_gfp+0x86/0x400 fs/buffer.c:1485
 sb_bread include/linux/buffer_head.h:346 [inline]
 get_branch+0x2c3/0x6e0 fs/sysv/itree.c:102
 get_block+0x180/0x16d0 fs/sysv/itree.c:222
 block_read_full_folio+0x3ee/0xae0 fs/buffer.c:2396
 filemap_read_folio+0x148/0x3b0 mm/filemap.c:2348
 do_read_cache_folio+0x373/0x5b0 mm/filemap.c:3893
 read_mapping_folio include/linux/pagemap.h:1032 [inline]
 dir_get_folio fs/sysv/dir.c:64 [inline]
 sysv_find_entry+0x16c/0x590 fs/sysv/dir.c:154
 sysv_inode_by_name+0x98/0x2a0 fs/sysv/dir.c:370
 sysv_lookup+0x6b/0xe0 fs/sysv/namei.c:38
 __lookup_slow+0x28c/0x3f0 fs/namei.c:1791
 lookup_slow+0x53/0x70 fs/namei.c:1808
 walk_component fs/namei.c:2112 [inline]
 link_path_walk+0x99b/0xea0 fs/namei.c:2477
 path_lookupat+0xa9/0x450 fs/namei.c:2633
 filename_lookup+0x2a3/0x670 fs/namei.c:2663
 user_path_at+0x3a/0x60 fs/namei.c:3070
 do_mount fs/namespace.c:3893 [inline]
 __do_sys_mount fs/namespace.c:4107 [inline]
 __se_sys_mount+0x297/0x3c0 fs/namespace.c:4084
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb418185d29
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:00007fb418f8e038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb418376080 RCX: 00007fb418185d29
RDX: 0000000000000000 RSI: 0000000020000200 RDI: 00000000200001c0
RBP: 00007fb418201aa8 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000002a540d R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb418376080 R15: 00007ffd342c0328
 </TASK>