rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P7077/1:b..l rcu: (detected by 0, t=10503 jiffies, g=15949, q=104302 ncpus=2) task:syz.7.273 state:R running task stack:25336 pid:7077 tgid:7071 ppid:6784 task_flags:0x400140 flags:0x00080002 Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x15dd/0x52d0 kernel/sched/core.c:6908 preempt_schedule_irq+0x4d/0xa0 kernel/sched/core.c:7235 irqentry_exit+0x599/0x620 kernel/entry/common.c:239 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:trace_lock_acquire include/trace/events/lock.h:24 [inline] RIP: 0010:lock_acquire+0x50/0x2e0 kernel/locking/lockdep.c:5831 Code: 8b 05 84 78 7a 11 48 89 44 24 30 0f 1f 44 00 00 65 8b 05 87 78 7a 11 83 f8 08 0f 83 77 01 00 00 89 c0 48 0f a3 05 f0 0e 70 0e <73> 0d e8 d9 29 09 00 84 c0 0f 84 bc 01 00 00 83 3d ea 41 70 0e 00 RSP: 0018:ffffc90004c67160 EFLAGS: 00000297 RAX: 0000000000000001 RBX: ffffffff822fea77 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e75e420 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: ffffc90004c672f8 R11: ffffffff81b0bfa0 R12: 0000000000000002 R13: ffffffff8e75e420 R14: 0000000000000000 R15: 0000000000000000 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xc2b/0xdb0 mm/page_alloc.c:2978 __slab_free+0x263/0x2b0 mm/slub.c:5576 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_kmalloc+0x22/0xb0 mm/kasan/common.c:406 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x31c/0x660 mm/slub.c:5383 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] kobject_uevent_env+0x28c/0x9e0 lib/kobject_uevent.c:540 __kobject_del+0xd2/0x330 lib/kobject.c:601 kobject_cleanup lib/kobject.c:680 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x240/0x560 lib/kobject.c:737 netdev_queue_update_kobjects+0x5db/0x6c0 net/core/net-sysfs.c:2073 remove_queue_kobjects net/core/net-sysfs.c:2170 [inline] netdev_unregister_kobject+0x11f/0x450 net/core/net-sysfs.c:2325 unregister_netdevice_many_notify+0x1e0e/0x2370 net/core/dev.c:12449 ops_exit_rtnl_list net/core/net_namespace.c:187 [inline] ops_undo_list+0x3d3/0x940 net/core/net_namespace.c:248 setup_net+0x2f0/0x340 net/core/net_namespace.c:462 copy_net_ns+0x50e/0x730 net/core/net_namespace.c:581 create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130 unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:226 ksys_unshare+0x51d/0x930 kernel/fork.c:3174 __do_sys_unshare kernel/fork.c:3245 [inline] __se_sys_unshare kernel/fork.c:3243 [inline] __x64_sys_unshare+0x38/0x50 kernel/fork.c:3243 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f95f7b9c799 RSP: 002b:00007f95f89fa028 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f95f7e16090 RCX: 00007f95f7b9c799 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000006a040000 RBP: 00007f95f7c32c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f95f7e16128 R14: 00007f95f7e16090 R15: 00007ffd648d9c08