FYI, we noticed the following commit:

commit: aa5c2fd79ff4016228d3cdf96f4b3556ba100249 ("Generic XDP")
url: https://github.com/0day-ci/linux/commits/David-Miller/Generic-XDP/20170413-072710


in testcase: boot

on test machine: qemu-system-x86_64 -enable-kvm -m 420M

caused below changes (please refer to attached dmesg/kmsg for entire log/backtrace):


+---------------------------------------------------------+------------+------------+
|                                                         | d92be7a41e | aa5c2fd79f |
+---------------------------------------------------------+------------+------------+
| boot_successes                                          | 12         | 0          |
| boot_failures                                           | 6          | 16         |
| invoked_oom-killer:gfp_mask=0x                          | 6          | 6          |
| Mem-Info                                                | 6          | 6          |
| Out_of_memory:Kill_process                              | 6          | 6          |
| net/core/dev.c:#suspicious_rcu_dereference_check()usage | 0          | 16         |
+---------------------------------------------------------+------------+------------+



[    6.797817] 
[    6.798554] ===============================
[    6.799881] [ ERR: suspicious RCU usage.  ]
[    6.801211] 4.11.0-rc5-01360-gaa5c2fd #26 Not tainted
[    6.802763] -------------------------------
[    6.804090] net/core/dev.c:7912 suspicious rcu_dereference_check() usage!
[    6.806662] 
[    6.806662] other info that might help us debug this:
[    6.806662] 
[    6.809387] 
[    6.809387] rcu_scheduler_active = 2, debug_locks = 0
[    6.811508] no locks held by swapper/0/1.
[    6.812801] 
[    6.812801] stack backtrace:
[    6.814443] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.11.0-rc5-01360-gaa5c2fd #26
[    6.816828] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-20161025_171302-gandalf 04/01/2014
[    6.819769] Call Trace:
[    6.820736]  dump_stack+0x82/0xb8
[    6.821884]  lockdep_rcu_suspicious+0xf7/0x100
[    6.823305]  free_netdev+0xf0/0x135
[    6.824523]  sbni_probe+0x287/0x2ba
[    6.825724]  ? set_debug_rodata+0x12/0x12
[    6.827026]  net_olddevs_init+0x14/0x72
[    6.828273]  ? probe_list2+0x50/0x50
[    6.829479]  do_one_initcall+0x90/0x142
[    6.831001]  ? set_debug_rodata+0x12/0x12
[    6.832295]  kernel_init_freeable+0x1d0/0x258
[    6.833695]  ? rest_init+0x13b/0x13b
[    6.834897]  kernel_init+0xe/0xf5
[    6.836043]  ret_from_fork+0x31/0x40
[    6.861563] tun: Universal TUN/TAP device driver, 1.6
[    6.863348] arcnet: arcnet loaded
[    6.864497] arcnet:rfc1201: RFC1201 "standard" (`a') encapsulation support loaded
[    6.866859] arcnet:rfc1051: RFC1051 "simple standard" (`s') encapsulation support loaded
[    6.869379] arcnet:arc_rawmode: raw mode (`r') encapsulation support loaded


To reproduce:

        git clone https://github.com/01org/lkp-tests.git
        cd lkp-tests
        bin/lkp qemu -k <bzImage> job-script  # job-script is attached in this email



Thanks,
Kernel Test Robot