INFO: task kworker/u8:12:5940 blocked for more than 143 seconds. Not tainted 6.15.0-rc1-syzkaller-00139-gab59a8605604 #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:12 state:D stack:23512 pid:5940 tgid:5940 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x116f/0x5de0 kernel/sched/core.c:6767 __schedule_loop kernel/sched/core.c:6845 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6860 afs_cell_purge+0x41f/0x4f0 fs/afs/cell.c:893 afs_net_exit+0x83/0x140 fs/afs/main.c:146 ops_exit_list+0xb0/0x180 net/core/net_namespace.c:172 cleanup_net+0x5c1/0xb30 net/core/net_namespace.c:654 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by ksoftirqd/1/23: 1 lock held by khungtaskd/31: #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] #0: ffffffff8e3c1580 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6764 2 locks held by getty/5576: #0: ffff8880324270a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222 3 locks held by kworker/0:3/5865: #0: ffff88801b478d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc90005497d18 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88805b9c1240 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x1bb/0x2e80 drivers/net/netdevsim/fib.c:1490 3 locks held by kworker/u8:12/5940: #0: ffff88801c2f3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc900055b7d18 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffffffff90115f10 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xc9/0xb30 net/core/net_namespace.c:608 1 lock held by syz-executor/13976: #0: ffffffff8e3cc980 (rcu_state.barrier_mutex){+.+.}-{4:4}, at: rcu_barrier+0x48/0x6e0 kernel/rcu/tree.c:3774 6 locks held by syz-executor/14079: #0: ffff888024c68420 (sb_writers#8){.+.+}-{0:0}, at: ksys_write+0x12a/0x240 fs/read_write.c:736 #1: ffff888036469c88 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x28f/0x510 fs/kernfs/file.c:325 #2: ffff888144fc5f08 (kn->active#49){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x2b2/0x510 fs/kernfs/file.c:326 #3: ffffffff8f6c62c8 (nsim_bus_dev_list_lock){+.+.}-{4:4}, at: del_device_store+0xd1/0x4a0 drivers/net/netdevsim/bus.c:216 #4: ffff88805e8520e8 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:922 [inline] #4: ffff88805e8520e8 (&dev->mutex){....}-{4:4}, at: __device_driver_lock drivers/base/dd.c:1095 [inline] #4: ffff88805e8520e8 (&dev->mutex){....}-{4:4}, at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1293 #5: ffff88805e856250 (&devlink->lock_key#25){+.+.}-{4:4}, at: nsim_drv_remove+0x4a/0x1d0 drivers/net/netdevsim/dev.c:1675 1 lock held by dhcpcd-run-hook/14188: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc1-syzkaller-00139-gab59a8605604 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 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:158 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline] watchdog+0xf70/0x12c0 kernel/hung_task.c:437 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 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: 14193 Comm: sed Not tainted 6.15.0-rc1-syzkaller-00139-gab59a8605604 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x12/0xc0 kernel/rcu/tree.c:736 Code: 84 00 00 00 00 00 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 55 53 65 ff 05 43 e8 05 12 e8 be 64 d1 09 <48> c7 c3 e8 fd a7 93 89 c5 83 f8 07 0f 87 82 00 00 00 48 8d 3c ed RSP: 0018:ffffc900039df478 EFLAGS: 00000282 RAX: 0000000000000001 RBX: ffffffff8e3c1580 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff8bf46540 RDI: ffffffff8bf46580 RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000010b77 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f4598afe500(0000) GS:ffff888124ab3000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4598cf28e5 CR3: 000000007aeb4000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x2cd/0x350 kernel/locking/lockdep.c:5829 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] class_rcu_constructor include/linux/rcupdate.h:1155 [inline] unwind_next_frame+0xd1/0x20a0 arch/x86/kernel/unwind_orc.c:479 arch_stack_walk+0x94/0x100 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x8e/0xc0 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:250 [inline] slab_post_alloc_hook mm/slub.c:4151 [inline] slab_alloc_node mm/slub.c:4200 [inline] kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4207 vm_area_dup+0x25/0x760 kernel/fork.c:488 __split_vma+0x17f/0x1030 mm/vma.c:477 split_vma mm/vma.c:553 [inline] vma_modify+0x33f/0x410 mm/vma.c:1547 vma_modify_flags+0x212/0x2d0 mm/vma.c:1565 mprotect_fixup+0x2b3/0xb10 mm/mprotect.c:658 do_mprotect_pkey+0x9ca/0xd50 mm/mprotect.c:832 __do_sys_mprotect mm/mprotect.c:853 [inline] __se_sys_mprotect mm/mprotect.c:850 [inline] __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:850 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4598e24bb7 Code: 00 00 00 b8 0b 00 00 00 0f 05 48 3d 01 f0 ff ff 73 01 c3 48 8d 0d b9 46 01 00 f7 d8 89 01 48 83 c8 ff c3 b8 0a 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8d 0d 99 46 01 00 f7 d8 89 01 48 83 RSP: 002b:00007ffdf6b1d7c8 EFLAGS: 00000206 ORIG_RAX: 000000000000000a RAX: ffffffffffffffda RBX: 00007f4598dff3d0 RCX: 00007f4598e24bb7 RDX: 0000000000000001 RSI: 0000000000003000 RDI: 00007f4598dfb000 RBP: 00007ffdf6b1d8e0 R08: 00007ffdf6b1d758 R09: 00007f4598dff3d0 R10: 00007f4598d40b48 R11: 0000000000000206 R12: 00007f4598dff3d0 R13: 00007f4598e2ceda R14: 00007f4598dfdf28 R15: 00007f4598dfd2b8