syzbot

INFO: task syz-executor.4:21540 blocked for more than 143 seconds.
      Not tainted 6.1.90-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4  state:D stack:25192 pid:21540 ppid:20808  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
 rwsem_down_read_slowpath kernel/locking/rwsem.c:1094 [inline]
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read+0x6ff/0xa30 kernel/locking/rwsem.c:1522
 iterate_supers+0xac/0x1e0 fs/super.c:744
 ksys_sync+0xb9/0x1c0 fs/sync.c:102
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f7da667dd69
RSP: 002b:00007f7da74740c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f7da67abf80 RCX: 00007f7da667dd69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f7da66ca49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f7da67abf80 R15: 00007ffe02acc1e8
 </TASK>
INFO: task syz-executor.0:21598 blocked for more than 143 seconds.
      Not tainted 6.1.90-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.0  state:D stack:25192 pid:21598 ppid:20892  flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
 rwsem_down_read_slowpath kernel/locking/rwsem.c:1094 [inline]
 __down_read_common kernel/locking/rwsem.c:1261 [inline]
 __down_read kernel/locking/rwsem.c:1274 [inline]
 down_read+0x6ff/0xa30 kernel/locking/rwsem.c:1522
 iterate_supers+0xac/0x1e0 fs/super.c:744
 ksys_sync+0xb9/0x1c0 fs/sync.c:102
 __do_sys_sync+0xa/0x10 fs/sync.c:113
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f748fc7dd69
RSP: 002b:00007f7490a3a0c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f748fdabf80 RCX: 00007f748fc7dd69
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f748fcca49e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007f748fdabf80 R15: 00007ffd729cef58
 </TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffffffff8d12ae50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
 #0: ffffffff8d12b650 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by khungtaskd/28:
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
 #0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
2 locks held by getty/3305:
 #0: ffff888028db6098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
 #1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
2 locks held by kworker/u4:12/5622:
1 lock held by syz-executor.3/17330:
 #0: ffff88801ab120e0 (&type->s_umount_key#51/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228
1 lock held by syz-executor.2/17508:
 #0: ffff8880592500e0 (&type->s_umount_key#51/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228
1 lock held by syz-executor.4/21540:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744
1 lock held by syz-executor.0/21598:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744
1 lock held by syz-executor.3/21678:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744
1 lock held by syz-executor.3/22001:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744
1 lock held by syz-executor.0/22070:
 #0: ffff8880791840e0 (&type->s_umount_key#51/1){+.+.}-{3:3}, at: alloc_super+0x217/0x930 fs/super.c:228
1 lock held by syz-executor.4/22157:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744
1 lock held by syz-executor.1/22396:
 #0: ffff88801ab120e0 (&type->s_umount_key#52){++++}-{3:3}, at: iterate_supers+0xac/0x1e0 fs/super.c:744

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

NMI backtrace for cpu 1
CPU: 1 PID: 28 Comm: khungtaskd Not tainted 6.1.90-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
 watchdog+0xf88/0xfd0 kernel/hung_task.c:377
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 11 Comm: kworker/u4:1 Not tainted 6.1.90-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: bat_events batadv_nc_worker
RIP: 0010:__lock_acquire+0x184/0x1f80 kernel/locking/lockdep.c:4957
Code: 29 c3 48 c1 fb 06 48 b9 ab aa aa aa aa aa aa aa 48 0f af cb 48 89 c8 48 89 8c 24 80 00 00 00 41 89 cf 48 85 f6 4c 89 6c 24 48 <0f> 84 35 01 00 00 49 8d 9d e0 0a 00 00 83 fe 30 0f 87 18 1b 00 00
RSP: 0018:ffffc900001079a0 EFLAGS: 00000002
RAX: 000000000000002c RBX: 0000000000000084 RCX: 000000000000002c
RDX: dffffc0000000000 RSI: 0000000000000002 RDI: ffffffff8d12ac80
RBP: ffff88813febc658 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000000
R13: ffff88813febbb80 R14: ffffffff8d12ac80 R15: 000000000000002c
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcd11f7b978 CR3: 0000000075e4e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
 rcu_read_lock include/linux/rcupdate.h:791 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:408 [inline]
 batadv_nc_worker+0xe8/0x610 net/batman-adv/network-coding.c:719
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>