INFO: task syz.0.81:3701 blocked for more than 430 seconds. Not tainted 6.15.0-syzkaller-10402-g4cb6c8af8591 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.81 state:D stack:0 pid:3701 tgid:3700 ppid:3312 task_flags:0x400140 flags:0x00000019 Call trace: __switch_to+0x208/0x4f4 arch/arm64/kernel/process.c:735 (T) context_switch kernel/sched/core.c:5392 [inline] __schedule+0xd34/0x3184 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0xd0/0x344 kernel/sched/core.c:6874 schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6931 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x5d8/0x9d8 kernel/locking/mutex.c:746 mutex_lock_nested+0x24/0x30 kernel/locking/mutex.c:798 nbd_start_device_ioctl drivers/block/nbd.c:1542 [inline] __nbd_ioctl drivers/block/nbd.c:1602 [inline] nbd_ioctl+0x224/0xa08 drivers/block/nbd.c:1642 blkdev_ioctl+0x22c/0x7f4 block/ioctl.c:704 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x124/0x1a4 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x198 arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x10c/0x138 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 INFO: task syz.0.81:3704 blocked for more than 430 seconds. Not tainted 6.15.0-syzkaller-10402-g4cb6c8af8591 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.81 state:D stack:0 pid:3704 tgid:3700 ppid:3312 task_flags:0x480140 flags:0x00000001 Call trace: __switch_to+0x208/0x4f4 arch/arm64/kernel/process.c:735 (T) context_switch kernel/sched/core.c:5392 [inline] __schedule+0xd34/0x3184 kernel/sched/core.c:6781 __schedule_loop kernel/sched/core.c:6859 [inline] schedule+0xd0/0x344 kernel/sched/core.c:6874 blk_mq_freeze_queue_wait+0xfc/0x140 block/blk-mq.c:190 blk_mq_freeze_queue_nomemsave+0x20/0x30 block/blk-mq.c:206 blk_mq_freeze_queue include/linux/blk-mq.h:934 [inline] queue_limits_commit_update_frozen+0x94/0x120 block/blk-settings.c:482 nbd_set_size+0x3b8/0x558 drivers/block/nbd.c:374 __nbd_ioctl drivers/block/nbd.c:1593 [inline] nbd_ioctl+0x5b0/0xa08 drivers/block/nbd.c:1642 blkdev_ioctl+0x22c/0x7f4 block/ioctl.c:704 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __arm64_sys_ioctl+0x124/0x1a4 fs/ioctl.c:893 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x6c/0x258 arch/arm64/kernel/syscall.c:49 el0_svc_common.constprop.0+0xac/0x230 arch/arm64/kernel/syscall.c:132 do_el0_svc+0x40/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x50/0x198 arch/arm64/kernel/entry-common.c:767 el0t_64_sync_handler+0x10c/0x138 arch/arm64/kernel/entry-common.c:786 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 Showing all locks held in the system: 3 locks held by kworker/u8:1/26: #0: ffff000018011948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x6f8/0x18d4 kernel/workqueue.c:3213 #1: ffff80008d6c7c80 ((work_completion)(&(&net->ipv6.addr_chk_work)->work)){+.+.}-{0:0}, at: process_one_work+0x71c/0x18d4 kernel/workqueue.c:3213 #2: ffff8000888a5a68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x1c/0x28 net/core/rtnetlink.c:80 1 lock held by khungtaskd/33: #0: ffff80008733fde0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x18/0x1c4 kernel/locking/lockdep.c:6764 2 locks held by getty/3253: #0: ffff0000180b40a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340 #1: ffff80008d5db2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x3e4/0xdb4 drivers/tty/n_tty.c:2222 2 locks held by syz-executor/3306: 5 locks held by kworker/u8:9/3468: 1 lock held by udevd/3694: #0: ffff000014d39358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x2c4/0xa84 block/bdev.c:945 1 lock held by syz.0.81/3701: #0: ffff000014c17230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_start_device_ioctl drivers/block/nbd.c:1542 [inline] #0: ffff000014c17230 (&nbd->config_lock){+.+.}-{4:4}, at: __nbd_ioctl drivers/block/nbd.c:1602 [inline] #0: ffff000014c17230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x224/0xa08 drivers/block/nbd.c:1642 4 locks held by syz.0.81/3704: #0: ffff000014c17230 (&nbd->config_lock){+.+.}-{4:4}, at: nbd_ioctl+0x100/0xa08 drivers/block/nbd.c:1635 #1: ffff000014a77238 (&q->limits_lock){+.+.}-{4:4}, at: queue_limits_start_update include/linux/blkdev.h:1002 [inline] #1: ffff000014a77238 (&q->limits_lock){+.+.}-{4:4}, at: nbd_set_size+0x214/0x558 drivers/block/nbd.c:354 #2: ffff000014a76be8 (&q->q_usage_counter(io)#33){++++}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x18/0x30 block/blk-mq.c:205 #3: ffff000014a76c20 (&q->q_usage_counter(queue)){+.+.}-{0:0}, at: blk_mq_freeze_queue_nomemsave+0x18/0x30 block/blk-mq.c:205 1 lock held by syz.1.350/4579: #0: ffff8000888a5a68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock+0x1c/0x28 net/core/rtnetlink.c:80 2 locks held by syz.2.355/4595: #0: ffff00001b3ff6d0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfc/0x800 net/netlink/af_netlink.c:2388 #1: ffff8000888a5a68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline] #1: ffff8000888a5a68 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x128/0x1a4 net/core/rtnetlink.c:6812 =============================================