hi,
openwrt 15.05 hg255d + usb-8187l router restart´╝îttl info

[    9.540000] mount_root: switching to jffs2 overlay
[    9.590000] procd: - early -
[    9.600000] procd: - watchdog -
[   10.500000] procd: - ubus -
[   11.540000] procd: - init -
Please press Enter to activate this console.
[   13.900000] l2tp_core: L2TP core driver, V2.0
[   13.910000] l2tp_netlink: L2TP netlink interface
[   13.920000] gre: GRE over IPv4 demultiplexor driver
[   13.950000] ip_gre: GRE over IPv4 tunneling driver
[   13.970000] Loading modules backported from Linux version master-2015-03-09-0-g141f155
[   13.980000] Backport generated by backports.git backports-20150129-0-gdd4a670
[   14.020000] nf_conntrack version 0.5.0 (456 buckets, 1824 max)
[   14.110000] xt_time: kernel timezone is -0000
[   14.180000] cfg80211: Calling CRDA to update world regulatory domain
[   14.200000] ip_tables: (C) 2000-2006 Netfilter Core Team
[   14.240000] cfg80211: World regulatory domain updated:
[   14.250000] cfg80211:  DFS Master region: unset
[   14.250000] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp), (dfs_cac_time)
[   14.270000] cfg80211:   (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm), (N/A)
[   14.290000] cfg80211:   (2457000 KHz - 2482000 KHz @ 20000 KHz, 92000 KHz AUTO), (N/A, 2000 mBm), (N/A)
[   14.310000] cfg80211:   (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm), (N/A)
[   14.330000] cfg80211:   (5170000 KHz - 5250000 KHz @ 80000 KHz, 160000 KHz AUTO), (N/A, 2000 mBm), (N/A)
[   14.340000] cfg80211:   (5250000 KHz - 5330000 KHz @ 80000 KHz, 160000 KHz AUTO), (N/A, 2000 mBm), (0 s)
[   14.360000] cfg80211:   (5490000 KHz - 5730000 KHz @ 160000 KHz), (N/A, 2000 mBm), (0 s)
[   14.380000] cfg80211:   (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm), (N/A)
[   14.400000] cfg80211:   (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm), (N/A)
[   14.490000] PPP generic driver version 2.4.2
[   14.510000] PPP MPPE Compression module registered
[   14.520000] NET: Registered protocol family 24
[   14.530000] PPTP driver version 0.8.5
[   14.570000] usbcore: registered new interface driver rt73usb
[   14.590000] l2tp_ppp: PPPoL2TP kernel driver, V2.0
[   14.620000] usbcore: registered new interface driver rt2500usb
[   14.650000] ieee80211 phy0: rt2x00_set_rt: Info - RT chipset 2872, rev 0200 detected
[   14.670000] ieee80211 phy0: rt2x00_set_rf: Info - RF chipset 0008 detected
[   14.690000] usbcore: registered new interface driver rt2800usb
[   21.230000] rtl8187 1-1:1.0: no of_node; not parsing pinctrl DT
[   22.190000] ieee80211 phy1: Selected rate control algorithm 'minstrel_ht'
[   22.210000] ieee80211 phy1: hwaddr 00:25:22:42:f8:4c, RTL8187vB (default) V1 + rtl8225z2, rfkill mask 2
[   22.240000] rtl8187: Customer ID is 0x00
[   22.260000] rtl8187: wireless switch is on
[   22.260000] usbcore: registered new interface driver rtl8187
[   26.390000] random: nonblocking pool is initialized
[   27.780000] 8021q: adding VLAN 0 to HW filter on device eth0
[   27.830000] device eth0.1 entered promiscuous mode
[   27.840000] device eth0 entered promiscuous mode
[   27.870000] br-lan: port 1(eth0.1) entered forwarding state
[   27.880000] br-lan: port 1(eth0.1) entered forwarding state
[   29.880000] br-lan: port 1(eth0.1) entered forwarding state
[   31.770000] cfg80211: Calling CRDA for country: CN
[   31.890000] cfg80211: Regulatory domain changed to country: CN
[   31.900000] cfg80211:  DFS Master region: FCC
[   31.910000] cfg80211:   (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp), (dfs_cac_time)
[   31.930000] cfg80211:   (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 3000 mBm), (N/A)
[   31.940000] cfg80211:   (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 3000 mBm), (N/A)
[   31.960000] cfg80211:   (4910000 KHz - 4990000 KHz @ 40000 KHz), (N/A, 3000 mBm), (N/A)
[   31.980000] cfg80211:   (5030000 KHz - 5090000 KHz @ 40000 KHz), (N/A, 3000 mBm), (N/A)
[   31.990000] cfg80211:   (5170000 KHz - 5250000 KHz @ 80000 KHz, 160000 KHz AUTO), (N/A, 3000 mBm), (N/A)
[   32.010000] cfg80211:   (5250000 KHz - 5330000 KHz @ 80000 KHz, 160000 KHz AUTO), (N/A, 3000 mBm), (0 s)
[   32.030000] cfg80211:   (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 3000 mBm), (N/A)
[   32.050000] cfg80211:   (57240000 KHz - 59400000 KHz @ 2160000 KHz), (N/A, 3000 mBm), (N/A)
[   32.060000] cfg80211:   (59400000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 4400 mBm), (N/A)
[   32.080000] cfg80211:   (63720000 KHz - 65880000 KHz @ 2160000 KHz), (N/A, 3000 mBm), (N/A)
[   34.740000] device wlan0 entered promiscuous mode
[   34.820000] br-lan: port 2(wlan0) entered forwarding state
[   34.830000] br-lan: port 2(wlan0) entered forwarding state
[   36.830000] br-lan: port 2(wlan0) entered forwarding state
[   46.830000] br-lan: port 2(wlan0) entered disabled state
[   46.840000] device wlan0 left promiscuous mode
[   46.850000] br-lan: port 2(wlan0) entered disabled state
[   47.690000] device wlan0 entered promiscuous mode
[   47.700000] br-lan: port 2(wlan0) entered forwarding state
[   47.710000] br-lan: port 2(wlan0) entered forwarding state
[   49.710000] br-lan: port 2(wlan0) entered forwarding state
[   49.950000] wlan1: authenticate with 74:44:01:02:a3:e7
[   50.260000] wlan1: send auth to 74:44:01:02:a3:e7 (try 1/3)
[   50.270000] wlan1: authenticated
[   50.300000] rtl8187 1-1:1.0 wlan1: disabling HT as WMM/QoS is not supported by the AP
[   50.310000] rtl8187 1-1:1.0 wlan1: disabling VHT as WMM/QoS is not supported by the AP
[   50.340000] wlan1: associate with 74:44:01:02:a3:e7 (try 1/3)
[   50.370000] wlan1: RX AssocResp from 74:44:01:02:a3:e7 (capab=0x431 status=0 aid=5)
[   50.410000] wlan1: associated
[   50.490000] device wlan0 left promiscuous mode
[   50.500000] br-lan: port 2(wlan0) entered disabled state
[   50.570000] wlan1: deauthenticating from 74:44:01:02:a3:e7 by local choice (Reason: 3=DEAUTH_LEAVING)
[   54.180000] device wlan0 entered promiscuous mode
[   54.190000] br-lan: port 2(wlan0) entered forwarding state
[   54.200000] br-lan: port 2(wlan0) entered forwarding state
[   56.200000] br-lan: port 2(wlan0) entered forwarding state
[   56.830000] wlan1: authenticate with 74:44:01:02:a3:e7
[   57.160000] wlan1: send auth to 74:44:01:02:a3:e7 (try 1/3)
[   57.170000] wlan1: authenticated
[   57.180000] rtl8187 1-1:1.0 wlan1: disabling HT as WMM/QoS is not supported by the AP
[   57.200000] rtl8187 1-1:1.0 wlan1: disabling VHT as WMM/QoS is not supported by the AP
[   57.220000] wlan1: associate with 74:44:01:02:a3:e7 (try 1/3)
[   57.230000] wlan1: RX AssocResp from 74:44:01:02:a3:e7 (capab=0x431 status=0 aid=5)
[   57.250000] wlan1: associated
[  118.390000] CPU 0 Unable to handle kernel paging request at virtual address 0000002c, epc == 81b24b04, ra == 81b24aac
[  118.410000] Oops[#1]:
[  118.410000] CPU: 0 PID: 188 Comm: kworker/u2:2 Not tainted 3.18.23 #1
[  118.410000] task: 818b3548 ti: 81918000 task.ti: 81918000
[  118.410000] $ 0   : 00000000 00000001 00000000 00000002
[  118.410000] $ 4   : 80f9361c 80c43000 81b6407c 80c4303c
[  118.410000] $ 8   : 00000000 80008b50 881d7d34 7fe041de
[  118.410000] $12   : 00b90000 802a0b34 00000000 37323530
[  118.410000] $16   : 80f93200 80f93080 81b64010 81b64200
[  118.410000] $20   : 00000000 81b14b30 00000020 80f93600
[  118.410000] $24   : 00000002 8001f844                 
[  118.410000] $28   : 81918000 81919818 00000001 81b24aac
[  118.410000] Hi    : 00000013
[  118.410000] Lo    : 00000004
[  118.410000] epc   : 81b24b04 dwc2_hcd_select_transactions+0x568/0x6d8 [dwc2]
[  118.410000]     Not tainted
[  118.410000] ra    : 81b24aac dwc2_hcd_select_transactions+0x510/0x6d8 [dwc2]
[  118.410000] Status: 1100e403 KERNEL EXL IE
[  118.410000] Cause : 00800008
[  118.410000] BadVA : 0000002c
[  118.410000] PrId  : 0001964c (MIPS 24KEc)
[  118.410000] Modules linked in: rtl8187 rt2800usb rt2800soc rt2800mmio rt2800lib rt2500usb pppoe ppp_async l2tp_ppp iptable_nat rt73usb rt2x00usb rt2x00soc rt2x00mmio rt2x00lib pptp pppox ppp_mppe ppp_generic nf_nat_ipv4 nf_conntrack_ipv4 mac80211 iptable_raw iptable_mangle iptable_filter ipt_REJECT ipt_MASQUERADE ip_tables cfg80211 xt_time xt_tcpudp xt_state xt_nat xt_multiport xt_mark xt_mac xt_limit xt_id xt_conntrack xt_comment xt_TCPMSS xt_REDIRECT xt_LOG xt_CT x_tables slhc nf_reject_ipv4 nf_nat_masquerade_ipv4 nf_nat_ftp nf_nat nf_log_ipv4 nf_log_common nf_defrag_ipv4 nf_conntrack_rtcache nf_conntrack_ftp nf_conntrack crc_itu_t crc_ccitt compat ip_gre gre l2tp_netlink l2tp_core udp_tunnel ip_tunnel eeprom_93cx6 sha1_generic ecb arc4 crypto_blkcipher leds_gpio dwc2_platform dwc2 ohci_platform ohci_hcd ehci_platform ehci_hcd gpio_button_hotplug usbcore nls_base usb_common aead crypto_hash
[  118.410000] Process kworker/u2:2 (pid: 188, threadinfo=81918000, task=818b3548, tls=00000000)
[  118.410000] Stack : 8056bcec 80e15df8 00800400 80008ac0 00000000 00000000 81b64200 80f93200
          00000020 0b008058 80f93208 818eeb00 00000000 00000000 00008058 81b483c8
          00000000 80e06dd0 80d80980 81b284e0 81b3d200 00000000 8056bcec 8056bd1c
          23d5f378 d8644f10 07152073 7eeda58e 35649684 b8d6bd94 b5c2e406 0d5090d6
          2685bb21 7fe041de 881d7d34 9c9ad148 25000001 4cf84222 00000000 0300ae08
          ...
[  118.410000] Call Trace:
[  118.410000] [<81b24b04>] dwc2_hcd_select_transactions+0x568/0x6d8 [dwc2]
[  118.410000]
[  118.410000]
Code: 14620006  00000000  8ee20014 <8c42002c> 30420001  10400027  8fa20010  41716000  32310001
[  118.880000] ---[ end trace f557057ca5563ed8 ]---
[  118.900000] Kernel panic - not syncing: Fatal exception in interrupt
[  118.900000] Rebooting in 3 seconds..

U-Boot 1.1.3 (Aug 23 2012 - 03:59:07)

SoC:Ralink RT305x
Memory Testing.......32768K OK.
DRAM:  32 MB
relocate_code Pointer at: 81168000
config usb..
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