INFO: task syz.4.131:7321 blocked for more than 143 seconds. Tainted: G W 6.12.0-rc3-syzkaller-g9ec59cb3edc7 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.131 state:D stack:0 pid:7321 tgid:7292 ppid:6848 flags:0x00000001 Call trace: __switch_to+0x428/0x860 arch/arm64/kernel/process.c:701 (T) context_switch kernel/sched/core.c:5322 [inline] __schedule+0x14bc/0x2718 kernel/sched/core.c:6682 __schedule_loop kernel/sched/core.c:6759 [inline] schedule+0xbc/0x238 kernel/sched/core.c:6774 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6831 __mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:684 __mutex_lock kernel/locking/mutex.c:752 [inline] mutex_lock_nested+0x2c/0x38 kernel/locking/mutex.c:804 fdget_pos+0x214/0x2a0 fs/file.c:1160 ksys_read+0x8c/0x26c fs/read_write.c:703 __do_sys_read fs/read_write.c:722 [inline] __se_sys_read fs/read_write.c:720 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:720 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:744 el0t_64_sync_handler+0x84/0x108 arch/arm64/kernel/entry-common.c:762 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffff80008f9d0520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:336 3 locks held by kworker/u8:2/42: #0: ffff0000d1d01148 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff800097f97c20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 #2: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 3 locks held by kworker/u8:7/2107: #0: ffff0000c0031148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff80009fd37c20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 #2: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 4 locks held by kworker/u8:9/3525: #0: ffff0000c1891948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x628/0x1600 kernel/workqueue.c:3203 #1: ffff8000a2cf7c20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x6bc/0x1600 kernel/workqueue.c:3203 #2: ffff8000926f5650 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x13c/0x9b4 net/core/net_namespace.c:580 #3: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 2 locks held by getty/6185: #0: ffff0000d80580a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80009b7ce2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2211 1 lock held by syz.4.131/7293: 2 locks held by syz.4.131/7319: 1 lock held by syz.4.131/7320: 1 lock held by syz.4.131/7321: #0: ffff0000dbcc62b8 (&f->f_pos_lock){+.+.}-{3:3}, at: fdget_pos+0x214/0x2a0 fs/file.c:1160 1 lock held by syz-executor/8460: #0: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x5e8/0xa9c net/core/rtnetlink.c:6672 2 locks held by syz-executor/8480: #0: ffff800092762f10 (cb_lock){++++}-{3:3}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:1218 #1: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 1 lock held by syz.2.354/8735: #0: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x5e8/0xa9c net/core/rtnetlink.c:6672 1 lock held by syz.3.358/8761: #0: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 2 locks held by syz.0.371/8824: #0: ffff800092762f10 (cb_lock){++++}-{3:3}, at: genl_rcv+0x28/0x50 net/netlink/genetlink.c:1218 #1: ffff800092701b68 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x20/0x2c net/core/rtnetlink.c:79 =============================================