INFO: task syz.0.996:9388 blocked for more than 144 seconds. Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.996 state:D stack:26032 pid:9388 tgid:9385 ppid:6953 flags:0x00024000 Call Trace: context_switch kernel/sched/core.c:5369 [inline] __schedule+0xe58/0x5ad0 kernel/sched/core.c:6756 __schedule_loop kernel/sched/core.c:6833 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6848 schedule_timeout+0x244/0x280 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 io_wq_exit_workers io_uring/io-wq.c:1249 [inline] io_wq_put_and_exit+0x232/0x8a0 io_uring/io-wq.c:1277 io_uring_clean_tctx+0x10e/0x190 io_uring/tctx.c:205 io_uring_cancel_generic+0x676/0x8e0 io_uring/io_uring.c:3203 io_uring_files_cancel include/linux/io_uring.h:20 [inline] do_exit+0x541/0x2d70 kernel/exit.c:894 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 get_signal+0x24ed/0x26c0 kernel/signal.c:3017 arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218 do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f5eca57ff19 RSP: 002b:00007f5ecb3f7058 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: 0000000000004600 RBX: 00007f5eca745fa0 RCX: 00007f5eca57ff19 RDX: 000000000000ff2e RSI: 0000000020000140 RDI: 0000000000000009 RBP: 00007f5eca5f3cc8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f5eca745fa0 R15: 00007ffe08c7a0c8 Showing all locks held in the system: 5 locks held by kworker/0:1/9: #0: ffff88801e6fad48 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3204 #1: ffffc900000e7d80 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffff88802961c190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1014 [inline] #2: ffff88802961c190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1c1/0x4e10 drivers/usb/core/hub.c:5849 #3: ffff88802961f510 (&port_dev->status_lock){+.+.}-{4:4}, at: usb_lock_port drivers/usb/core/hub.c:3206 [inline] #3: ffff88802961f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5418 [inline] #3: ffff88802961f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #3: ffff88802961f510 (&port_dev->status_lock){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5821 [inline] #3: ffff88802961f510 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x27ec/0x4e10 drivers/usb/core/hub.c:5903 #4: ffff8880292cbe68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect drivers/usb/core/hub.c:5419 [inline] #4: ffff8880292cbe68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_port_connect_change drivers/usb/core/hub.c:5661 [inline] #4: ffff8880292cbe68 (hcd->address0_mutex){+.+.}-{4:4}, at: port_event drivers/usb/core/hub.c:5821 [inline] #4: ffff8880292cbe68 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x2815/0x4e10 drivers/usb/core/hub.c:5903 1 lock held by khungtaskd/30: #0: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8e1bb500 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6744 3 locks held by kworker/0:2/933: #0: ffff88801b078948 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x1293/0x1ba0 kernel/workqueue.c:3204 #1: ffffc90004257d80 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x921/0x1ba0 kernel/workqueue.c:3205 #2: ffffffff8e1c6e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 2 locks held by getty/5576: #0: ffff8880368ba0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 1 lock held by iou-wrk-9388/9390: 1 lock held by iou-wrk-9388/9391: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9392: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9393: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9394: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9395: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9396: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 1 lock held by iou-wrk-9388/9397: #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_ring_submit_lock io_uring/io_uring.h:254 [inline] #0: ffff8880128800a8 (&ctx->uring_lock){+.+.}-{4:4}, at: io_provide_buffers+0x906/0xdc0 io_uring/kbuf.c:580 2 locks held by syz.4.1398/10840: #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: ppp_release+0x167/0x230 drivers/net/ppp/ppp_generic.c:408 #1: ffffffff8e1c6e38 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 1 lock held by syz-executor/10966: #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: netdev_wait_allrefs_any net/core/dev.c:10786 [inline] #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: netdev_run_todo+0xdfc/0x12d0 net/core/dev.c:10905 3 locks held by syz.3.1499/11236: #0: ffff88806343cd80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_dev_do_close+0x26/0x90 net/bluetooth/hci_core.c:481 #1: ffff88806343c078 (&hdev->lock){+.+.}-{4:4}, at: hci_dev_close_sync+0x3ab/0x11a0 net/bluetooth/hci_sync.c:5200 #2: ffffffff90142dc8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_disconn_cfm include/net/bluetooth/hci_core.h:2047 [inline] #2: ffffffff90142dc8 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_conn_hash_flush+0xbb/0x260 net/bluetooth/hci_conn.c:2698 1 lock held by syz.1.1500/11237: #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517 1 lock held by syz.5.1501/11240: #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517 1 lock held by syz.4.1502/11244: #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_detach drivers/net/tun.c:698 [inline] #0: ffffffff8feda988 (rtnl_mutex){+.+.}-{4:4}, at: tun_chr_close+0x38/0x230 drivers/net/tun.c:3517 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:234 [inline] watchdog+0xf14/0x1240 kernel/hung_task.c:397 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 9392 Comm: iou-wrk-9388 Not tainted 6.13.0-rc2-syzkaller-00018-g7cb1b4663150 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 RIP: 0010:__lock_acquire+0x38e/0x3c40 kernel/locking/lockdep.c:5163 Code: 38 d0 7c 08 84 d2 0f 85 24 2b 00 00 41 83 bd c4 0a 00 00 01 49 8d 7f 24 44 89 e0 8b 14 24 83 d8 ff c1 e5 0f c1 e0 0d c1 e1 10 <0f> b7 ed 09 e8 81 e1 00 00 03 00 c1 e2 12 81 e2 00 00 04 00 09 c8 RSP: 0018:ffffc90003c76df8 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000020000 RDX: 0000000000000000 RSI: ffff888026040ac4 RDI: ffff888026040b2c RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000001 R10: 0000000000000005 R11: 0000000000000002 R12: 0000000000000000 R13: ffff888026040000 R14: 0000000000000021 R15: ffff888026040b08 FS: 00007f5ecb3f76c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020068000 CR3: 0000000035ed6000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: lock_acquire.part.0+0x11b/0x380 kernel/locking/lockdep.c:5849 rcu_lock_acquire include/linux/rcupdate.h:337 [inline] rcu_read_lock include/linux/rcupdate.h:849 [inline] list_lru_count_one+0x40/0x310 mm/list_lru.c:255 list_lru_shrink_count include/linux/list_lru.h:168 [inline] super_cache_count+0x1da/0x300 fs/super.c:264 do_shrink_slab+0x82/0x11c0 mm/shrinker.c:384 shrink_slab_memcg mm/shrinker.c:550 [inline] shrink_slab+0xa1c/0x12a0 mm/shrinker.c:628 shrink_node_memcgs mm/vmscan.c:5931 [inline] shrink_node+0xa10/0x3e60 mm/vmscan.c:5970 shrink_zones mm/vmscan.c:6215 [inline] do_try_to_free_pages+0x35f/0x1a30 mm/vmscan.c:6277 try_to_free_mem_cgroup_pages+0x31a/0x7a0 mm/vmscan.c:6609 try_charge_memcg+0x356/0xaf0 mm/memcontrol.c:2238 obj_cgroup_charge_pages mm/memcontrol.c:2646 [inline] obj_cgroup_charge+0x179/0x4d0 mm/memcontrol.c:2937 __memcg_slab_post_alloc_hook+0x1b6/0x9b0 mm/memcontrol.c:2998 memcg_slab_post_alloc_hook mm/slub.c:2152 [inline] slab_post_alloc_hook mm/slub.c:4114 [inline] slab_alloc_node mm/slub.c:4153 [inline] kmem_cache_alloc_noprof+0x366/0x3d0 mm/slub.c:4160 io_refill_buffer_cache+0x3e9/0x4f0 io_uring/kbuf.c:535 io_add_buffers io_uring/kbuf.c:556 [inline] io_provide_buffers+0x61e/0xdc0 io_uring/kbuf.c:606 io_issue_sqe+0x175/0x1200 io_uring/io_uring.c:1736 io_wq_submit_work+0x3fc/0xec0 io_uring/io_uring.c:1845 io_worker_handle_work+0x4e5/0x1680 io_uring/io-wq.c:601 io_wq_worker+0x33f/0xdf0 io_uring/io-wq.c:655 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244