INFO: task syz.0.3160:18070 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.3160 state:D stack:27416 pid:18070 tgid:18065 ppid:15075 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ba859ce59 RSP: 002b:00007f3ba94ff028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f3ba8816090 RCX: 00007f3ba859ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f3ba8816090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3ba8816128 R14: 00007f3ba8816090 R15: 00007ffe7e5234b8 INFO: task syz.0.3160:18072 blocked for more than 144 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.3160 state:D stack:27336 pid:18072 tgid:18065 ppid:15075 task_flags:0x400040 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5388 [inline] __schedule+0x1295/0x67a0 kernel/sched/core.c:7189 __schedule_loop kernel/sched/core.c:7268 [inline] schedule+0xdd/0x390 kernel/sched/core.c:7283 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7340 __mutex_lock_common kernel/locking/mutex.c:726 [inline] __mutex_lock+0xced/0x1b10 kernel/locking/mutex.c:820 sync_bdevs+0x153/0x480 block/bdev.c:1296 ksys_sync+0xb0/0xf0 fs/sync.c:105 __do_sys_sync+0xe/0x20 fs/sync.c:111 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f3ba859ce59 RSP: 002b:00007f3ba94de028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2 RAX: ffffffffffffffda RBX: 00007f3ba8816180 RCX: 00007f3ba859ce59 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f3ba8816180 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3ba8816218 R14: 00007f3ba8816180 R15: 00007ffe7e5234b8 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline] #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline] #0: ffffffff8e7e5560 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 2 locks held by getty/5371: #0: ffff888037b770a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000322b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x14f0 drivers/tty/n_tty.c:2211 1 lock held by udevd/5633: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0x41a/0xe40 block/bdev.c:953 3 locks held by kworker/u8:12/6131: #0: ffff888032aff940 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90006b47d08 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #2: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x11f/0x1360 net/ipv6/addrconf.c:4208 3 locks held by kworker/u8:15/11540: #0: ffff88801c6c0940 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90005b4fd08 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff905eb148 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x920 net/core/net_namespace.c:673 4 locks held by kworker/u8:17/15928: #0: ffff88801bbb4940 ((wq_completion)ib-unreg-wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90005fafd08 ((work_completion)(&device->unregistration_work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffff8880984c46f8 (&device->unregistration_lock){+.+.}-{4:4}, at: __ib_unregister_device+0x23b/0x480 drivers/infiniband/core/device.c:1524 #3: ffffffff902198c8 (devices_rwsem){++++}-{4:4}, at: ib_device_disable_gid_updates+0x19/0x70 drivers/infiniband/core/device.c:2448 1 lock held by syz.0.3160/18070: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.0.3160/18072: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.4.3273/18532: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.4.3273/18539: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.5.3346/18825: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.5.3346/18828: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 3 locks held by kworker/u8:18/19203: #0: ffff8880212bd940 ((wq_completion)gid-cache-wq){+.+.}-{0:0}, at: process_one_work+0x12d6/0x1980 kernel/workqueue.c:3289 #1: ffffc90005347d08 ((work_completion)(&ndev_work->work)){+.+.}-{0:0}, at: process_one_work+0x973/0x1980 kernel/workqueue.c:3290 #2: ffffffff902198c8 (devices_rwsem){++++}-{4:4}, at: ib_enum_all_roce_netdevs+0x89/0x150 drivers/infiniband/core/device.c:2416 1 lock held by syz.8.3499/19501: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.8.3499/19503: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.7.3586/19875: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.7.3586/19880: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.9.3595/19908: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz.9.3595/19909: #0: ffff888027ac1350 (&disk->open_mutex){+.+.}-{4:4}, at: sync_bdevs+0x153/0x480 block/bdev.c:1296 1 lock held by syz-executor/19979: #0: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline] #0: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: inet_rtm_newaddr+0x30c/0x18b0 net/ipv4/devinet.c:978 7 locks held by syz.3.3629/20096: #0: ffffffff9b4c7d88 (&rdma_nl_types[idx].sem){.+.+}-{4:4}, at: rdma_nl_rcv_msg+0x168/0x6f0 drivers/infiniband/core/netlink.c:164 #1: ffffffff9022ec08 (link_ops_rwsem){++++}-{4:4}, at: nldev_newlink+0x2f0/0x620 drivers/infiniband/core/nldev.c:1803 #2: ffffffff902198c8 (devices_rwsem){++++}-{4:4}, at: enable_device_and_get+0x103/0x3f0 drivers/infiniband/core/device.c:1331 #3: ffffffff90219648 (rdma_nets_rwsem){++++}-{4:4}, at: add_compat_devs drivers/infiniband/core/device.c:1034 [inline] #3: ffffffff90219648 (rdma_nets_rwsem){++++}-{4:4}, at: enable_device_and_get+0x2ce/0x3f0 drivers/infiniband/core/device.c:1347 #4: ffff88805f0c4fe0 (&device->compat_devs_mutex){+.+.}-{4:4}, at: add_one_compat_dev+0x112/0x820 drivers/infiniband/core/device.c:952 #5: ffff88805f0c52d0 (&rxe->usdev_lock){+.+.}-{4:4}, at: rxe_query_port+0x115/0x330 drivers/infiniband/sw/rxe/rxe_verbs.c:61 #6: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: ib_get_eth_speed+0x12f/0xb40 drivers/infiniband/core/verbs.c:2054 8 locks held by syz-executor/20098: #0: ffff888035bb8410 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x250 fs/read_write.c:740 #1: ffff88806aebb880 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x2c2/0x5f0 fs/kernfs/file.c:343 #2: ffff8880297673c8 (kn->active#52){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff8880297673c8 (kn->active#52){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x332/0x5f0 fs/kernfs/file.c:344 #3: ffffffff8fb84cc0 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x480 drivers/net/netdevsim/bus.c:234 #4: ffff88807e1c3128 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1040 [inline] #4: ffff88807e1c3128 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1174 [inline] #4: ffff88807e1c3128 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xb2/0x620 drivers/base/dd.c:1372 #5: ffff88807e1c7258 (&devlink->lock_key#7){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1e0 drivers/net/netdevsim/dev.c:1799 #6: ffffffff90603ea0 (rtnl_mutex){+.+.}-{4:4}, at: nsim_destroy+0x19e/0x970 drivers/net/netdevsim/netdev.c:1188 #7: ffffffff8e7f10a8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x27f/0x3c0 kernel/rcu/tree_exp.h:311 2 locks held by syz-executor/20137: #0: ffffffff905eb148 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x451/0x7c0 net/core/net_namespace.c:575 #1: ffffffff902198c8 (devices_rwsem){++++}-{4:4}, at: rdma_dev_init_net+0x28c/0x590 drivers/infiniband/core/device.c:1188 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:353 [inline] watchdog+0xcb1/0x1030 kernel/hung_task.c:561 kthread+0x370/0x450 kernel/kthread.c:436 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63 Code: a6 92 02 e9 43 44 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 23 f2 21 00 fb f4 cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90 RSP: 0018:ffffc90000197df0 EFLAGS: 00000242 RAX: 000000000513319b RBX: ffff88801e2b2540 RCX: ffffffff8b89a225 RDX: 0000000000000000 RSI: ffffffff8df0fe0d RDI: ffffffff8c1c4780 RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed10170a67b5 R10: ffff8880b8533dab R11: 0000000000000000 R12: 0000000000000001 R13: ffffed1003c564a8 R14: 0000000000000001 R15: ffffffff90d71950 FS: 0000000000000000(0000) GS:ffff888124487000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffcd7f14f52 CR3: 000000007879c000 CR4: 00000000003526f0 Call Trace: arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline] default_idle+0x9/0x10 arch/x86/kernel/process.c:767 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122 cpuidle_idle_call kernel/sched/idle.c:199 [inline] do_idle+0x464/0x590 kernel/sched/idle.c:352 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312 common_startup_64+0x13e/0x148