syzbot

INFO: task syz-executor272:8249 blocked for more than 143 seconds.
      Not tainted 6.6.0-rc4-syzkaller-00281-g59f3fd30af35 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor272 state:D stack:26928 pid:8249  ppid:5098   flags:0x00000006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5382 [inline]
 __schedule+0xee1/0x5a10 kernel/sched/core.c:6695
 schedule+0xe7/0x1b0 kernel/sched/core.c:6771
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:6830
 rwsem_down_write_slowpath+0x53d/0x12a0 kernel/locking/rwsem.c:1178
 __down_write_common kernel/locking/rwsem.c:1306 [inline]
 __down_write kernel/locking/rwsem.c:1315 [inline]
 down_write_nested+0x1d7/0x200 kernel/locking/rwsem.c:1690
 inode_lock_nested include/linux/fs.h:837 [inline]
 filename_create+0x1c2/0x530 fs/namei.c:3889
 do_mkdirat+0xb3/0x330 fs/namei.c:4135
 __do_sys_mkdir fs/namei.c:4163 [inline]
 __se_sys_mkdir fs/namei.c:4161 [inline]
 __x64_sys_mkdir+0xf2/0x140 fs/namei.c:4161
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe8c3216d99
RSP: 002b:00007fe8c31cf168 EFLAGS: 00000246 ORIG_RAX: 0000000000000053
RAX: ffffffffffffffda RBX: 00007fe8c329f6e8 RCX: 00007fe8c3216d99
RDX: 00007fe8c3216d99 RSI: 0000000000000000 RDI: 0000000020000000
RBP: 00007fe8c329f6e0 R08: 00007fe8c31cf6c0 R09: 0000000000000000
R10: 00007fe8c31cf6c0 R11: 0000000000000246 R12: 00007fe8c329f6ec
R13: 0000000000000006 R14: 00007ffc8ed1ff00 R15: 00007ffc8ed1ffe8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/29:
 #0: ffffffff8cbab2a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:303 [inline]
 #0: ffffffff8cbab2a0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:749 [inline]
 #0: ffffffff8cbab2a0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x75/0x340 kernel/locking/lockdep.c:6613
2 locks held by kworker/u4:7/239:
2 locks held by kworker/u4:9/2854:
 #0: ffff888012c71938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x787/0x15c0 kernel/workqueue.c:2605
 #1: ffff8880b9828888 (&per_cpu_ptr(group->pcpu, cpu)->seq){-.-.}-{0:0}, at: psi_task_switch+0x2d9/0x900 kernel/sched/psi.c:999
2 locks held by getty/4796:
 #0: ffff8880268920a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031232f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfc5/0x1480 drivers/tty/n_tty.c:2206
1 lock held by syz-executor272/5099:
 #0: ffffffff8cbb6b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:325 [inline]
 #0: ffffffff8cbb6b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x404/0x7e0 kernel/rcu/tree_exp.h:992
1 lock held by syz-executor272/5100:
 #0: ffffffff8cbb6b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:293 [inline]
 #0: ffffffff8cbb6b78 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x69e/0x7e0 kernel/rcu/tree_exp.h:992
2 locks held by kworker/u4:0/5133:
2 locks held by udevd/5136:
2 locks held by udevd/5224:
2 locks held by syz-executor272/8249:
 #0: ffff88806ea22410 (sb_writers#11){.+.+}-{0:0}, at: filename_create+0x10d/0x530 fs/namei.c:3882
 #1: ffff88807161eab0 (&sb->s_type->i_mutex_key#19/1){+.+.}-{3:3}, at: inode_lock_nested include/linux/fs.h:837 [inline]
 #1: ffff88807161eab0 (&sb->s_type->i_mutex_key#19/1){+.+.}-{3:3}, at: filename_create+0x1c2/0x530 fs/namei.c:3889
3 locks held by syz-executor272/8263:

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

NMI backtrace for cpu 0
CPU: 0 PID: 29 Comm: khungtaskd Not tainted 6.6.0-rc4-syzkaller-00281-g59f3fd30af35 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x277/0x380 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x299/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xf87/0x1210 kernel/hung_task.c:379
 kthread+0x33c/0x440 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 8263 Comm: syz-executor272 Not tainted 6.6.0-rc4-syzkaller-00281-g59f3fd30af35 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023
RIP: 0010:lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline]
RIP: 0010:lock_is_held_type+0x59/0x140 kernel/locking/lockdep.c:5823
Code: 0f 85 cb 00 00 00 65 4c 8b 24 25 c0 bc 03 00 41 8b 94 24 c4 0a 00 00 85 d2 0f 85 b2 00 00 00 48 89 fd 41 89 f6 9c 8f 04 24 fa <48> c7 c7 e0 ad 8c 8a 45 31 ff e8 38 10 00 00 41 8b 84 24 c0 0a 00
RSP: 0018:ffffc9000cbbf608 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 1ffff92001977ecb RCX: 0000000000000001
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffffffff8cbab240
RBP: ffffffff8cbab240 R08: 0000000000000007 R09: 0000018000000000
R10: 0000018000000000 R11: 1ffffffff1976c99 R12: ffff888013acd940
R13: 00000000ffffffff R14: 00000000ffffffff R15: ffff88806ea22018
FS:  00007fe8c31ae6c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fe8badc2000 CR3: 000000007813f000 CR4: 0000000000350ee0
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_is_held include/linux/lockdep.h:288 [inline]
 __might_resched+0x478/0x5e0 kernel/sched/core.c:10149
 __getblk_gfp fs/buffer.c:1437 [inline]
 __bread_gfp+0x3f/0x310 fs/buffer.c:1473
 sb_bread include/linux/buffer_head.h:326 [inline]
 exfat_get_dentry+0x1a9/0x6b0 fs/exfat/dir.c:770
 exfat_readdir+0x528/0x1510 fs/exfat/dir.c:121
 exfat_iterate+0x3ce/0xae0 fs/exfat/dir.c:261
 wrap_directory_iterator+0xa5/0xe0 fs/readdir.c:67
 iterate_dir+0x1e5/0x5f0 fs/readdir.c:106
 __do_sys_getdents64 fs/readdir.c:405 [inline]
 __se_sys_getdents64 fs/readdir.c:390 [inline]
 __x64_sys_getdents64+0x14f/0x2e0 fs/readdir.c:390
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7fe8c3216d99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 1a 00 00 90 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe8c31ae168 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fe8c329f6f8 RCX: 00007fe8c3216d99
RDX: 0000000000000098 RSI: 0000000020000080 RDI: 0000000000000004
RBP: 00007fe8c329f6f0 R08: 00007fe8c31ae6c0 R09: 0000000000000000
R10: 00007fe8c31ae6c0 R11: 0000000000000246 R12: 00007fe8c329f6fc
R13: 000000000000006e R14: 00007ffc8ed1ff00 R15: 00007ffc8ed1ffe8
 </TASK>