INFO: task kworker/u8:21:11359 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:21 state:D stack:22456 pid:11359 tgid:11359 ppid:2 task_flags:0x4208160 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 rdma_dev_exit_net+0x203/0x340 drivers/infiniband/core/device.c:1144 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:253 cleanup_net+0x4c5/0x8a0 net/core/net_namespace.c:686 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 INFO: task syz.3.4412:19811 blocked for more than 143 seconds. Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.3.4412 state:D stack:25864 pid:19811 tgid:19810 ppid:15727 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 rdma_dev_exit_net+0x203/0x340 drivers/infiniband/core/device.c:1144 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:253 setup_net+0x3e2/0x4b0 net/core/net_namespace.c:457 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:574 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3375 __do_sys_unshare kernel/fork.c:3446 [inline] __se_sys_unshare kernel/fork.c:3444 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3444 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3f05d8e969 RSP: 002b:00007f3f06b4f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f3f05fb5fa0 RCX: 00007f3f05d8e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000062040200 RBP: 00007f3f05e10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f3f05fb5fa0 R15: 00007ffddd89e188 INFO: task syz.4.4423:19847 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.4.4423 state:D stack:22920 pid:19847 tgid:19846 ppid:16073 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_timeout+0x9a/0x270 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x2bf/0x5d0 kernel/sched/completion.c:148 disable_device+0x1c6/0x320 drivers/infiniband/core/device.c:1288 __ib_unregister_device+0x2cb/0x3f0 drivers/infiniband/core/device.c:1516 ib_unregister_device_and_put+0xb8/0xf0 drivers/infiniband/core/device.c:1581 nldev_dellink+0x2d1/0x320 drivers/infiniband/core/nldev.c:1826 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:-1 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x6ab/0x980 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x75b/0x8d0 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 ____sys_sendmsg+0x505/0x830 net/socket.c:2566 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2620 __sys_sendmsg net/socket.c:2652 [inline] __do_sys_sendmsg net/socket.c:2657 [inline] __se_sys_sendmsg net/socket.c:2655 [inline] __x64_sys_sendmsg+0x19b/0x260 net/socket.c:2655 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd752b8e969 RSP: 002b:00007fd753acc038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fd752db5fa0 RCX: 00007fd752b8e969 RDX: 0000000000000000 RSI: 00002000000000c0 RDI: 0000000000000003 RBP: 00007fd752c10ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd752db5fa0 R15: 00007ffd032c6e48 INFO: task syz.0.4448:19935 blocked for more than 144 seconds. Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.4448 state:D stack:25896 pid:19935 tgid:19933 ppid:14581 task_flags:0x400140 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x16e2/0x4cd0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0x165/0x360 kernel/sched/core.c:6860 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917 __mutex_lock_common kernel/locking/mutex.c:678 [inline] __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:746 rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 rdma_dev_exit_net+0x203/0x340 drivers/infiniband/core/device.c:1144 ops_exit_list net/core/net_namespace.c:200 [inline] ops_undo_list+0x49a/0x990 net/core/net_namespace.c:253 setup_net+0x3e2/0x4b0 net/core/net_namespace.c:457 copy_net_ns+0x32e/0x590 net/core/net_namespace.c:574 create_new_namespaces+0x3d3/0x700 kernel/nsproxy.c:110 unshare_nsproxy_namespaces+0x11c/0x170 kernel/nsproxy.c:228 ksys_unshare+0x4c8/0x8c0 kernel/fork.c:3375 __do_sys_unshare kernel/fork.c:3446 [inline] __se_sys_unshare kernel/fork.c:3444 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3444 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc5e1f8e969 RSP: 002b:00007fc5dfdf6038 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007fc5e21b6080 RCX: 00007fc5e1f8e969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000068040200 RBP: 00007fc5e2010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc5e21b6080 R15: 00007ffed322d348 Showing all locks held in the system: 3 locks held by kworker/u8:1/13: 1 lock held by khungtaskd/31: #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764 3 locks held by kworker/u9:1/5141: #0: ffff8880580e0148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff8880580e0148 ((wq_completion)hci6){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9000f8a7c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9000f8a7c60 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffff888023890d80 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0 net/bluetooth/hci_sync.c:331 2 locks held by getty/5593: #0: ffff88814e6880a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000333b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222 4 locks held by kworker/u8:21/11359: #0: ffff88801aefe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff88801aefe148 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319 #1: ffffc9001c617c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc9001c617c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319 #2: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x8a0 net/core/net_namespace.c:662 #3: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.3.4412/19811: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.4.4423/19847: #0: ffffffff99bdb018 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:164 [inline] #0: ffffffff99bdb018 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] #0: ffffffff99bdb018 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv+0x302/0x980 drivers/infiniband/core/netlink.c:259 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x284/0x3f0 drivers/infiniband/core/device.c:1512 2 locks held by syz.0.4448/19935: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.6.4682/20870: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.2.4743/21088: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.5.5101/22396: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.7.5350/23218: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 2 locks held by syz.7.5350/23219: #0: ffffffff8f2eaf90 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:570 #1: ffff888064c5c6d0 (&device->unregistration_lock){+.+.}-{4:4}, at: rdma_dev_change_netns+0x39/0x300 drivers/infiniband/core/device.c:1664 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xfee/0x1030 kernel/hung_task.c:437 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted 6.15.0-rc6-syzkaller-01306-g3da895b23901 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Workqueue: events_unbound nsim_dev_trap_report_work RIP: 0010:check_preemption_disabled+0x35/0x120 lib/smp_processor_id.c:55 Code: 48 8b 05 4e 4e 1e 07 48 89 44 24 08 65 8b 05 56 4e 1e 07 65 8b 0d 4b 4e 1e 07 f7 c1 ff ff ff 7f 74 23 65 48 8b 0d 2b 4e 1e 07 <48> 3b 4c 24 08 0f 85 cc 00 00 00 48 83 c4 10 5b 41 5e 41 5f 5d e9 RSP: 0018:ffffc90000127480 EFLAGS: 00000202 RAX: 0000000000000000 RBX: ffffffff90929701 RCX: 29ef03f0bca01900 RDX: ffffc90000127501 RSI: ffffffff8bc1dbc0 RDI: ffffffff8bc1db80 RBP: dffffc0000000000 R08: ffffc90000127a20 R09: 0000000000000000 R10: ffffc900001275f8 R11: fffff52000024ec1 R12: ffffc90000127a30 R13: ffffc90000120000 R14: ffffc900001275a8 R15: ffffffff8171ca05 FS: 0000000000000000(0000) GS:ffff8881260b7000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa7a1580178 CR3: 0000000031cb4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:736 rcu_read_unlock include/linux/rcupdate.h:869 [inline] class_rcu_destructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0x1965/0x2390 arch/x86/kernel/unwind_orc.c:680 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4327 [inline] __kmalloc_node_track_caller_noprof+0x271/0x4e0 mm/slub.c:4346 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:601 __alloc_skb+0x142/0x2d0 net/core/skbuff.c:670 alloc_skb include/linux/skbuff.h:1336 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:748 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:805 [inline] nsim_dev_trap_report_work+0x29a/0xb80 drivers/net/netdevsim/dev.c:851 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xade/0x17a0 kernel/workqueue.c:3319 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3400 kthread+0x711/0x8a0 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245