INFO: task syz.5.88:4684 blocked for more than 143 seconds. Not tainted 6.1.115-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.88 state:D stack:24512 pid:4684 ppid:4348 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5241 [inline] __schedule+0x143f/0x4570 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 rwsem_down_write_slowpath+0xea1/0x14b0 kernel/locking/rwsem.c:1189 mmap_write_lock include/linux/mmap_lock.h:71 [inline] exit_mmap+0x29a/0x9f0 mm/mmap.c:3235 __mmput+0x115/0x3c0 kernel/fork.c:1199 exit_mm+0x226/0x300 kernel/exit.c:565 do_exit+0x9f6/0x26a0 kernel/exit.c:858 do_group_exit+0x202/0x2b0 kernel/exit.c:1021 get_signal+0x16f7/0x17d0 kernel/signal.c:2870 arch_do_signal_or_restart+0xb0/0x1a10 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f67eb77e719 RSP: 002b:00007f67ec58a0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: 0000000000000001 RBX: 00007f67eb935f88 RCX: 00007f67eb77e719 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f67eb935f8c RBP: 00007f67eb935f80 R08: 0000000000000010 R09: 0000000000000000 R10: 0000000000000007 R11: 0000000000000246 R12: 00007f67eb935f8c R13: 0000000000000000 R14: 00007ffce7432fd0 R15: 00007ffce74330b8 Showing all locks held in the system: 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8d32b1d0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8d32b9d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] #0: ffffffff8d32b000 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6510 1 lock held by klogd/3612: 2 locks held by getty/4006: #0: ffff888030d63098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc900032462f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2198 3 locks held by kworker/u4:7/4526: 1 lock held by syz.5.88/4684: #0: ffff88807dbfdb58 (&mm->mmap_lock){++++}-{3:3}, at: mmap_write_lock include/linux/mmap_lock.h:71 [inline] #0: ffff88807dbfdb58 (&mm->mmap_lock){++++}-{3:3}, at: exit_mmap+0x29a/0x9f0 mm/mmap.c:3235 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.115-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __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+0x1ae/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:295 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 56 Comm: kworker/u4:4 Not tainted 6.1.115-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: bat_events batadv_nc_worker RIP: 0010:hlock_class kernel/locking/lockdep.c:228 [inline] RIP: 0010:check_wait_context kernel/locking/lockdep.c:4748 [inline] RIP: 0010:__lock_acquire+0x794/0x1f80 kernel/locking/lockdep.c:4999 Code: 8b 5d 00 81 e3 ff 1f 00 00 48 89 d8 48 c1 e8 06 48 8d 3c c5 60 02 23 91 be 08 00 00 00 e8 e4 70 77 00 48 0f a3 1d 7c 5b b8 0f <73> 1b 48 8d 04 5b 48 c1 e0 06 48 8d 98 20 81 bb 90 48 ba 00 00 00 RSP: 0018:ffffc900015779a0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: 00000000000006bf RCX: ffffffff816aa6dc RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff91230330 RBP: ffff888020ae6468 R08: dffffc0000000000 R09: fffffbfff2246067 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000001 R13: ffff888020ae6468 R14: 0000000000000001 R15: 0000000000000004 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f1fbe479361 CR3: 000000000d08e000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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:295