syzbot

=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
6.1.36-syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor.5/20165 [HC0[0]:SC0[2]:HE1:SE0] is trying to acquire:
ffffffff8d0001e0 (fs_reclaim){+.+.}-{0:0}, at: might_alloc include/linux/sched/mm.h:271 [inline]
ffffffff8d0001e0 (fs_reclaim){+.+.}-{0:0}, at: slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710

and this task is already holding:
ffff88807ddc2108 (&sch->q.lock){+.-.}-{2:2}, at: netem_change+0x17e/0x1ea0 net/sched/sch_netem.c:969
which would create a new lock dependency:
 (&sch->q.lock){+.-.}-{2:2} -> (fs_reclaim){+.+.}-{0:0}

but this new dependency connects a SOFTIRQ-irq-safe lock:
 (&sch->q.lock){+.-.}-{2:2}

... which became SOFTIRQ-irq-safe at:
  lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
  __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
  _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
  spin_lock include/linux/spinlock.h:350 [inline]
  dev_requeue_skb+0x3d4/0x460 net/sched/sch_generic.c:148
  sch_direct_xmit+0x3d1/0x5e0
  __dev_xmit_skb net/core/dev.c:3822 [inline]
  __dev_queue_xmit+0x1ab4/0x3c90 net/core/dev.c:4227
  dev_queue_xmit include/linux/netdevice.h:3021 [inline]
  neigh_hh_output include/net/neighbour.h:528 [inline]
  neigh_output include/net/neighbour.h:542 [inline]
  ip6_finish_output2+0xf61/0x15b0 net/ipv6/ip6_output.c:134
  __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
  ip6_finish_output+0x6ac/0xa80 net/ipv6/ip6_output.c:206
  dst_output include/net/dst.h:444 [inline]
  NF_HOOK include/linux/netfilter.h:302 [inline]
  ndisc_send_skb+0xb04/0x1380 net/ipv6/ndisc.c:508
  addrconf_rs_timer+0x357/0x610 net/ipv6/addrconf.c:3936
  call_timer_fn+0x19e/0x6b0 kernel/time/timer.c:1474
  expire_timers kernel/time/timer.c:1519 [inline]
  __run_timers+0x67c/0x890 kernel/time/timer.c:1790
  run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
  __do_softirq+0x2e9/0xa4c kernel/softirq.c:571
  invoke_softirq kernel/softirq.c:445 [inline]
  __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
  irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
  sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
  asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
  get_current arch/x86/include/asm/current.h:15 [inline]
  pagefault_disabled include/linux/uaccess.h:228 [inline]
  __might_fault+0x25/0x110 mm/memory.c:5650
  _copy_from_user+0x26/0x170 lib/usercopy.c:14
  copy_from_user include/linux/uaccess.h:161 [inline]
  copy_msghdr_from_user+0xaa/0x670 net/socket.c:2413
  recvmsg_copy_msghdr net/socket.c:2667 [inline]
  ___sys_recvmsg net/socket.c:2739 [inline]
  do_recvmmsg+0x408/0xad0 net/socket.c:2837
  __sys_recvmmsg net/socket.c:2916 [inline]
  __do_sys_recvmmsg net/socket.c:2939 [inline]
  __se_sys_recvmmsg net/socket.c:2932 [inline]
  __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2932
  do_syscall_x64 arch/x86/entry/common.c:50 [inline]
  do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
  entry_SYSCALL_64_after_hwframe+0x63/0xcd

to a SOFTIRQ-irq-unsafe lock:
 (fs_reclaim){+.+.}-{0:0}

... which became SOFTIRQ-irq-unsafe at:
...
  lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
  __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
  fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
  might_alloc include/linux/sched/mm.h:271 [inline]
  slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
  slab_alloc_node mm/slub.c:3318 [inline]
  __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
  kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045
  kmalloc include/linux/slab.h:553 [inline]
  kzalloc include/linux/slab.h:689 [inline]
  alloc_workqueue_attrs+0x46/0xc0 kernel/workqueue.c:3394
  wq_numa_init+0x122/0x4b0 kernel/workqueue.c:5959
  workqueue_init+0x22/0x59d kernel/workqueue.c:6086
  kernel_init_freeable+0x40a/0x61f init/main.c:1614
  kernel_init+0x19/0x290 init/main.c:1519
  ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

other info that might help us debug this:

 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               local_irq_disable();
                               lock(&sch->q.lock);
                               lock(fs_reclaim);
  <Interrupt>
    lock(&sch->q.lock);

 *** DEADLOCK ***

2 locks held by syz-executor.5/20165:
 #0: ffffffff8e094968 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
 #0: ffffffff8e094968 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x720/0xf00 net/core/rtnetlink.c:6094
 #1: ffff88807ddc2108 (&sch->q.lock){+.-.}-{2:2}, at: netem_change+0x17e/0x1ea0 net/sched/sch_netem.c:969

the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&sch->q.lock){+.-.}-{2:2} {
   HARDIRQ-ON-W at:
                    lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                    __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
                    _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
                    spin_lock_bh include/linux/spinlock.h:355 [inline]
                    dev_reset_queue+0x131/0x1a0 net/sched/sch_generic.c:1291
                    netdev_for_each_tx_queue include/linux/netdevice.h:2453 [inline]
                    dev_deactivate_many+0x525/0xaf0 net/sched/sch_generic.c:1359
                    dev_deactivate+0x177/0x270 net/sched/sch_generic.c:1382
                    linkwatch_do_dev+0x104/0x160 net/core/link_watch.c:166
                    __linkwatch_run_queue+0x448/0x6b0 net/core/link_watch.c:221
                    linkwatch_event+0x48/0x50 net/core/link_watch.c:264
                    process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289
                    worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
                    kthread+0x26e/0x300 kernel/kthread.c:376
                    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
   IN-SOFTIRQ-W at:
                    lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                    __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
                    _raw_spin_lock+0x2a/0x40 kernel/locking/spinlock.c:154
                    spin_lock include/linux/spinlock.h:350 [inline]
                    dev_requeue_skb+0x3d4/0x460 net/sched/sch_generic.c:148
                    sch_direct_xmit+0x3d1/0x5e0
                    __dev_xmit_skb net/core/dev.c:3822 [inline]
                    __dev_queue_xmit+0x1ab4/0x3c90 net/core/dev.c:4227
                    dev_queue_xmit include/linux/netdevice.h:3021 [inline]
                    neigh_hh_output include/net/neighbour.h:528 [inline]
                    neigh_output include/net/neighbour.h:542 [inline]
                    ip6_finish_output2+0xf61/0x15b0 net/ipv6/ip6_output.c:134
                    __ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
                    ip6_finish_output+0x6ac/0xa80 net/ipv6/ip6_output.c:206
                    dst_output include/net/dst.h:444 [inline]
                    NF_HOOK include/linux/netfilter.h:302 [inline]
                    ndisc_send_skb+0xb04/0x1380 net/ipv6/ndisc.c:508
                    addrconf_rs_timer+0x357/0x610 net/ipv6/addrconf.c:3936
                    call_timer_fn+0x19e/0x6b0 kernel/time/timer.c:1474
                    expire_timers kernel/time/timer.c:1519 [inline]
                    __run_timers+0x67c/0x890 kernel/time/timer.c:1790
                    run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1803
                    __do_softirq+0x2e9/0xa4c kernel/softirq.c:571
                    invoke_softirq kernel/softirq.c:445 [inline]
                    __irq_exit_rcu+0x155/0x240 kernel/softirq.c:650
                    irq_exit_rcu+0x5/0x20 kernel/softirq.c:662
                    sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1106
                    asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
                    get_current arch/x86/include/asm/current.h:15 [inline]
                    pagefault_disabled include/linux/uaccess.h:228 [inline]
                    __might_fault+0x25/0x110 mm/memory.c:5650
                    _copy_from_user+0x26/0x170 lib/usercopy.c:14
                    copy_from_user include/linux/uaccess.h:161 [inline]
                    copy_msghdr_from_user+0xaa/0x670 net/socket.c:2413
                    recvmsg_copy_msghdr net/socket.c:2667 [inline]
                    ___sys_recvmsg net/socket.c:2739 [inline]
                    do_recvmmsg+0x408/0xad0 net/socket.c:2837
                    __sys_recvmmsg net/socket.c:2916 [inline]
                    __do_sys_recvmmsg net/socket.c:2939 [inline]
                    __se_sys_recvmmsg net/socket.c:2932 [inline]
                    __x64_sys_recvmmsg+0x195/0x240 net/socket.c:2932
                    do_syscall_x64 arch/x86/entry/common.c:50 [inline]
                    do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
                    entry_SYSCALL_64_after_hwframe+0x63/0xcd
   INITIAL USE at:
                   lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                   __raw_spin_lock_bh include/linux/spinlock_api_smp.h:126 [inline]
                   _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:178
                   spin_lock_bh include/linux/spinlock.h:355 [inline]
                   dev_reset_queue+0x131/0x1a0 net/sched/sch_generic.c:1291
                   netdev_for_each_tx_queue include/linux/netdevice.h:2453 [inline]
                   dev_deactivate_many+0x525/0xaf0 net/sched/sch_generic.c:1359
                   dev_deactivate+0x177/0x270 net/sched/sch_generic.c:1382
                   linkwatch_do_dev+0x104/0x160 net/core/link_watch.c:166
                   __linkwatch_run_queue+0x448/0x6b0 net/core/link_watch.c:221
                   linkwatch_event+0x48/0x50 net/core/link_watch.c:264
                   process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289
                   worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
                   kthread+0x26e/0x300 kernel/kthread.c:376
                   ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 }
 ... key      at: [<ffffffff91eacf60>] qdisc_alloc.__key+0x0/0x20

the dependencies between the lock to be acquired
 and SOFTIRQ-irq-unsafe lock:
-> (fs_reclaim){+.+.}-{0:0} {
   HARDIRQ-ON-W at:
                    lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                    __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
                    fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
                    might_alloc include/linux/sched/mm.h:271 [inline]
                    slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
                    slab_alloc_node mm/slub.c:3318 [inline]
                    __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
                    kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045
                    kmalloc include/linux/slab.h:553 [inline]
                    kzalloc include/linux/slab.h:689 [inline]
                    alloc_workqueue_attrs+0x46/0xc0 kernel/workqueue.c:3394
                    wq_numa_init+0x122/0x4b0 kernel/workqueue.c:5959
                    workqueue_init+0x22/0x59d kernel/workqueue.c:6086
                    kernel_init_freeable+0x40a/0x61f init/main.c:1614
                    kernel_init+0x19/0x290 init/main.c:1519
                    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
   SOFTIRQ-ON-W at:
                    lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                    __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
                    fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
                    might_alloc include/linux/sched/mm.h:271 [inline]
                    slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
                    slab_alloc_node mm/slub.c:3318 [inline]
                    __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
                    kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045
                    kmalloc include/linux/slab.h:553 [inline]
                    kzalloc include/linux/slab.h:689 [inline]
                    alloc_workqueue_attrs+0x46/0xc0 kernel/workqueue.c:3394
                    wq_numa_init+0x122/0x4b0 kernel/workqueue.c:5959
                    workqueue_init+0x22/0x59d kernel/workqueue.c:6086
                    kernel_init_freeable+0x40a/0x61f init/main.c:1614
                    kernel_init+0x19/0x290 init/main.c:1519
                    ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
   INITIAL USE at:
                   lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
                   __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
                   fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
                   might_alloc include/linux/sched/mm.h:271 [inline]
                   slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
                   slab_alloc_node mm/slub.c:3318 [inline]
                   __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
                   kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045
                   kmalloc include/linux/slab.h:553 [inline]
                   kzalloc include/linux/slab.h:689 [inline]
                   alloc_workqueue_attrs+0x46/0xc0 kernel/workqueue.c:3394
                   wq_numa_init+0x122/0x4b0 kernel/workqueue.c:5959
                   workqueue_init+0x22/0x59d kernel/workqueue.c:6086
                   kernel_init_freeable+0x40a/0x61f init/main.c:1614
                   kernel_init+0x19/0x290 init/main.c:1519
                   ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 }
 ... key      at: [<ffffffff8d0001e0>] __fs_reclaim_map+0x0/0xe0
 ... acquired at:
   lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
   __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
   fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
   might_alloc include/linux/sched/mm.h:271 [inline]
   slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
   slab_alloc_node mm/slub.c:3318 [inline]
   __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
   __do_kmalloc_node mm/slab_common.c:954 [inline]
   __kmalloc_node+0xa2/0x230 mm/slab_common.c:962
   kmalloc_node include/linux/slab.h:579 [inline]
   kvmalloc_node+0x6e/0x180 mm/util.c:581
   kvmalloc include/linux/slab.h:706 [inline]
   get_dist_table+0x91/0x380 net/sched/sch_netem.c:788
   netem_change+0x947/0x1ea0 net/sched/sch_netem.c:985
   netem_init+0x58/0xb0 net/sched/sch_netem.c:1072
   qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
   tc_modify_qdisc+0x9e0/0x1da0 net/sched/sch_api.c:1723
   rtnetlink_rcv_msg+0x776/0xf00 net/core/rtnetlink.c:6097
   netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2524
   netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
   netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
   netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1902
   sock_sendmsg_nosec net/socket.c:716 [inline]
   sock_sendmsg net/socket.c:736 [inline]
   ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
   ___sys_sendmsg net/socket.c:2536 [inline]
   __sys_sendmsg+0x2a9/0x390 net/socket.c:2565
   do_syscall_x64 arch/x86/entry/common.c:50 [inline]
   do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
   entry_SYSCALL_64_after_hwframe+0x63/0xcd


stack backtrace:
CPU: 1 PID: 20165 Comm: syz-executor.5 Not tainted 6.1.36-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_bad_irq_dependency kernel/locking/lockdep.c:2612 [inline]
 check_irq_usage kernel/locking/lockdep.c:2851 [inline]
 check_prev_add kernel/locking/lockdep.c:3102 [inline]
 check_prevs_add kernel/locking/lockdep.c:3217 [inline]
 validate_chain+0x4d2e/0x58e0 kernel/locking/lockdep.c:3832
 __lock_acquire+0x125b/0x1f80 kernel/locking/lockdep.c:5056
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5669
 __fs_reclaim_acquire mm/page_alloc.c:4683 [inline]
 fs_reclaim_acquire+0x83/0x120 mm/page_alloc.c:4697
 might_alloc include/linux/sched/mm.h:271 [inline]
 slab_pre_alloc_hook+0x2a/0x2a0 mm/slab.h:710
 slab_alloc_node mm/slub.c:3318 [inline]
 __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node+0xa2/0x230 mm/slab_common.c:962
 kmalloc_node include/linux/slab.h:579 [inline]
 kvmalloc_node+0x6e/0x180 mm/util.c:581
 kvmalloc include/linux/slab.h:706 [inline]
 get_dist_table+0x91/0x380 net/sched/sch_netem.c:788
 netem_change+0x947/0x1ea0 net/sched/sch_netem.c:985
 netem_init+0x58/0xb0 net/sched/sch_netem.c:1072
 qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
 tc_modify_qdisc+0x9e0/0x1da0 net/sched/sch_api.c:1723
 rtnetlink_rcv_msg+0x776/0xf00 net/core/rtnetlink.c:6097
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2524
 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
 netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1902
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2de0e8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2de1c2b168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2de0fabf80 RCX: 00007f2de0e8c389
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003
RBP: 00007f2de0ed7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffeb0c91ff R14: 00007f2de1c2b300 R15: 0000000000022000
 </TASK>
BUG: sleeping function called from invalid context at include/linux/sched/mm.h:274
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 20165, name: syz-executor.5
preempt_count: 201, expected: 0
RCU nest depth: 0, expected: 0
INFO: lockdep is turned off.
Preemption disabled at:
[<0000000000000000>] 0x0
CPU: 1 PID: 20165 Comm: syz-executor.5 Not tainted 6.1.36-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 __might_resched+0x5cb/0x780 kernel/sched/core.c:9941
 might_alloc include/linux/sched/mm.h:274 [inline]
 slab_pre_alloc_hook+0x4a/0x2a0 mm/slab.h:710
 slab_alloc_node mm/slub.c:3318 [inline]
 __kmem_cache_alloc_node+0x47/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:954 [inline]
 __kmalloc_node+0xa2/0x230 mm/slab_common.c:962
 kmalloc_node include/linux/slab.h:579 [inline]
 kvmalloc_node+0x6e/0x180 mm/util.c:581
 kvmalloc include/linux/slab.h:706 [inline]
 get_dist_table+0x91/0x380 net/sched/sch_netem.c:788
 netem_change+0x947/0x1ea0 net/sched/sch_netem.c:985
 netem_init+0x58/0xb0 net/sched/sch_netem.c:1072
 qdisc_create+0x8a1/0x1220 net/sched/sch_api.c:1314
 tc_modify_qdisc+0x9e0/0x1da0 net/sched/sch_api.c:1723
 rtnetlink_rcv_msg+0x776/0xf00 net/core/rtnetlink.c:6097
 netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2524
 netlink_unicast_kernel net/netlink/af_netlink.c:1328 [inline]
 netlink_unicast+0x7bf/0x990 net/netlink/af_netlink.c:1354
 netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1902
 sock_sendmsg_nosec net/socket.c:716 [inline]
 sock_sendmsg net/socket.c:736 [inline]
 ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x2a9/0x390 net/socket.c:2565
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f2de0e8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2de1c2b168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2de0fabf80 RCX: 00007f2de0e8c389
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003
RBP: 00007f2de0ed7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffeb0c91ff R14: 00007f2de1c2b300 R15: 0000000000022000
 </TASK>