INFO: task syz.0.2547:19355 blocked for more than 143 seconds. Not tainted 6.12.0-rc1-syzkaller-00306-g27cc6fdf7201 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.2547 state:D stack:25808 pid:19355 tgid:19355 ppid:17715 flags:0x00000004 Call Trace: context_switch kernel/sched/core.c:5315 [inline] __schedule+0xef5/0x5750 kernel/sched/core.c:6675 __schedule_loop kernel/sched/core.c:6752 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6767 schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116 wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264 coredump_wait fs/coredump.c:418 [inline] do_coredump+0x82f/0x4160 fs/coredump.c:575 get_signal+0x237c/0x26d0 kernel/signal.c:2902 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:328 [inline] irqentry_exit_to_user_mode+0x13f/0x280 kernel/entry/common.c:231 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623 RIP: 0033:0x7f09e0d45a5d RSP: 002b:00007ffde5515768 EFLAGS: 00010202 RAX: 0000000020000000 RBX: 0000000000000004 RCX: 800000000000003a RDX: 0000000000000003 RSI: 000000000000002c RDI: 0000000020000000 RBP: 00007f09e0f37a80 R08: 00007f09e0c00000 R09: 0000000000000001 R10: 0000000000000001 R11: 0000000000000009 R12: 00000000000fb792 R13: 00007ffde5515870 R14: 0000000000000032 R15: fffffffffffffffe Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720 1 lock held by dhcpcd/4898: #0: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6643 2 locks held by getty/4988: #0: ffff88802e4ea0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211 3 locks held by kworker/u8:17/7372: #0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204 #1: ffffc900049dfd80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:276 1 lock held by syz.2.692/9123: 1 lock held by syz.2.1060/10957: 1 lock held by syz.2.1294/12410: 5 locks held by kworker/u8:37/13910: #0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204 #1: ffffc9001050fd80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8faad210 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xb40 net/core/net_namespace.c:580 #3: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x8f/0x9b0 net/core/dev.c:11934 #4: ffffffff8ddc30f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297 3 locks held by kworker/u8:45/18794: #0: ffff88814bb07948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204 #1: ffffc90009137d80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205 #2: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcf/0x14d0 net/ipv6/addrconf.c:4196 1 lock held by syz.0.2547/19356: 1 lock held by syz-executor/20402: #0: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline] #0: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6643 4 locks held by syz-executor/20406: #0: ffff888070130420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:736 #1: ffff888030e53488 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff8881413cab48 (kn->active#50){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f068f28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: new_device_store+0x187/0x730 drivers/net/netdevsim/bus.c:166 7 locks held by syz-executor/20413: #0: ffff888070130420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12f/0x260 fs/read_write.c:736 #1: ffff888145b80088 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x27b/0x500 fs/kernfs/file.c:325 #2: ffff8881413cac38 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x29e/0x500 fs/kernfs/file.c:326 #3: ffffffff8f068f28 (nsim_bus_dev_list_lock){+.+.}-{3:3}, at: del_device_store+0xd2/0x4b0 drivers/net/netdevsim/bus.c:216 #4: ffff88804d0b70e8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:1014 [inline] #4: ffff88804d0b70e8 (&dev->mutex){....}-{3:3}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88804d0b70e8 (&dev->mutex){....}-{3:3}, at: device_release_driver_internal+0xa4/0x610 drivers/base/dd.c:1293 #5: ffff88804d0b5250 (&devlink->lock_key#52){+.+.}-{3:3}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1672 #6: ffffffff8fac2e28 (rtnl_mutex){+.+.}-{3:3}, at: nsim_destroy+0x6f/0x6b0 drivers/net/netdevsim/netdev.c:773 1 lock held by syz.2.2689/20586: #0: ffffffff8ddc30f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x1a4/0x3b0 kernel/rcu/tree_exp.h:329 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc1-syzkaller-00306-g27cc6fdf7201 #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:223 [inline] watchdog+0xf0c/0x1240 kernel/hung_task.c:379 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 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 936 Comm: kworker/1:2 Not tainted 6.12.0-rc1-syzkaller-00306-g27cc6fdf7201 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 Workqueue: events nsim_dev_trap_report_work RIP: 0010:preempt_count_sub+0x0/0x160 kernel/sched/core.c:5805 Code: 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 48 c7 c7 60 8e 2f 93 e9 80 5e 64 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1e fa 48 c7 c0 20 58 38 9a 53 89 fb 48 ba 00 00 00 00 00 fc RSP: 0018:ffffc90003aaf700 EFLAGS: 00000287 RAX: ffffc90003ab0001 RBX: ffffc90003aaff30 RCX: ffffc90003ab0001 RDX: ffffc90003aaff38 RSI: ffffc90003aaff00 RDI: 0000000000000001 RBP: ffffc90003aa8000 R08: ffffc90003aaf7ac R09: ffffffff90ae6726 R10: ffffc90003aaf778 R11: 000000000000587a R12: ffffc90003aaf7c8 R13: ffffc90003aaf778 R14: ffffc90003aaff30 R15: ffffc90003aaff28 FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6c02d22440 CR3: 000000006abf0000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: unwind_next_frame+0xe5d/0x20c0 arch/x86/kernel/unwind_orc.c:672 arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47 kasan_save_track+0x14/0x30 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:319 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:345 kasan_slab_alloc include/linux/kasan.h:247 [inline] slab_post_alloc_hook mm/slub.c:4085 [inline] slab_alloc_node mm/slub.c:4134 [inline] kmem_cache_alloc_node_noprof+0x153/0x310 mm/slub.c:4186 __alloc_skb+0x2b3/0x380 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1322 [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+0x2a4/0xc80 drivers/net/netdevsim/dev.c:850 process_one_work+0x958/0x1b30 kernel/workqueue.c:3229 process_scheduled_works kernel/workqueue.c:3310 [inline] worker_thread+0x6c8/0xf00 kernel/workqueue.c:3391 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