FYI, we noticed the below changes on

commit e4962a14435e15c0c070e8aa1b010454c9292c02 ("mac802154: add default interface registration")

Although many boot failure before and after the commit, there is one more dmesg as follow.

[  407.384353] DHCP/BOOTP: Ignoring device wpan0, MTU 127 too small

This may be expected behavior.  Just FYI.

+----------------------------------------------+------------+------------+
|                                              | bd28a11f25 | e4962a1443 |
+----------------------------------------------+------------+------------+
| boot_successes                               | 10         | 7          |
| boot_failures                                | 60         | 63         |
| BUG:kernel_boot_hang                         | 60         | 62         |
| INFO:rcu_sched_detected_stalls_on_CPUs/tasks | 18         | 13         |
| kernel_BUG_at_kernel/smpboot.c               | 0          | 1          |
| invalid_opcode                               | 0          | 1          |
| RIP:smpboot_thread_fn                        | 0          | 1          |
| Kernel_panic-not_syncing:Fatal_exception     | 0          | 1          |
+----------------------------------------------+------------+------------+


[  407.384353] DHCP/BOOTP: Ignoring device wpan0, MTU 127 too small
[  407.392309] IP-Config: Failed to open irlan0
[  407.796255] Sending DHCP requests ...
BUG: kernel boot hang
Elapsed time: 420
qemu-system-x86_64 -enable-kvm -kernel /kernel/x86_64-randconfig-n0-12151325/279071949e8c18a6dd242851539304f468da138f/vmlinuz-3.18.0-g2790719 -append 'user=lkp job=/lkp/scheduled/vm-vp-quantal-x86_64-58/rand_boot-1-quantal-core-x86_64.cgz-x86_64-randconfig-n0-12151325-279071949e8c18a6dd242851539304f468da138f-1.yaml ARCH=x86_64 BOOT_IMAGE=/kernel/x86_64-randconfig-n0-12151325/279071949e8c18a6dd242851539304f468da138f/vmlinuz-3.18.0-g2790719 kconfig=x86_64-randconfig-n0-12151325 commit=279071949e8c18a6dd242851539304f468da138f branch=linux-devel/devel-lkp-nhm1-smoke-201412152118 root=/dev/ram0 max_uptime=3600 RESULT_ROOT=/result/vm-vp-quantal-x86_64/boot/1/quantal-core-x86_64.cgz/x86_64-randconfig-n0-12151325/279071949e8c18a6dd242851539304f468da138f/0 ip=::::vm-vp-quantal-x86_64-58::dhcp earlyprintk=ttyS0,115200 debug apic=debug sysrq_always_enabled rcupdate.rcu_cpu_stall_timeout=100 panic=-1 softlockup_panic=1 nmi_watchdog=panic oops=panic load_ramdisk=2 prompt_ramdisk=0 console=ttyS0,115200 console=tty0 vga=normal rw drbd.minor_count=8'  -initrd /fs/sdb1/initrd-vm-vp-quantal-x86_64-58 -m 360 -smp 2 -net nic,vlan=1,model=e1000 -net user,vlan=1 -boot order=nc -no-reboot -watchdog i6300esb -rtc base=localtime -pidfile /dev/shm/kboot/pid-vm-vp-quantal-x86_64-58 -serial file:/dev/shm/kboot/serial-vm-vp-quantal-x86_64-58 -daemonize -display none -monitor null 


Thanks,
Huang, Ying