[ 83.663608] Unable to handle kernel NULL pointer dereference at virtual address 000008c0
[ 83.671724] pgd = 80004000
[ 83.674480] [000008c0] *pgd=00000000
[ 83.678094] Internal error: Oops: 17 [#1] PREEMPT SMP ARM
[ 83.683506] Modules linked in: bridge stp wlan
[ 83.688048] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.1.15 #3
[ 83.693983] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 83.700526] task: a8073440 ti: a80a2000 task.ti: a80a2000
[ 83.705982] PC is at br_dev_xmit+0xbc/0x138 [bridge]
[ 83.710983] LR is at br_dev_xmit+0xbc/0x138 [bridge]
[ 83.715967] pc : [<7f17b2c0>] lr : [<7f17b2c0>] psr: 200e0113
[ 83.715967] sp : a80a3cb0 ip : 00000000 fp : 80bd27cc
[ 83.727457] r10: a8c9a000 r9 : de000000 r8 : a8c9a4c0
[ 83.732686] r7 : a8c9a000 r6 : 000008c0 r5 : a89d0c00 r4 : ab723610
[ 83.739216] r3 : a8764802 r2 : 00000000 r1 : a8764810 r0 : a8764810
[ 83.745749] Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
[ 83.753063] Control: 10c53c7d Table: 38b2c04a DAC: 00000015
[ 83.758818] Process swapper/2 (pid: 0, stack limit = 0xa80a2210)
[ 83.764830] Stack: (0xa80a3cb0 to 0xa80a4000)
[ 83.769195] 3ca0: a89d0c00 80bcb31c a8c9a000 a89d0c00
[ 83.777380] 3cc0: a879c600 80695bf0 a8001d00 80bd27c4 00000000 00000000 a879c600 a80a3d24
[ 83.785566] 3ce0: 00000002 a879c600 de000000 806956f4 a87e0800 a89d0c00 80bcb31c a8c9a000
[ 83.793750] 3d00: 00000002 a879c600 de000000 de000000 dad012a5 806960d8 00000000 806a0254
[ 83.801935] 3d20: 00000000 fffffff4 a8bf3800 a89d0c00 a8a70400 00000000 16000000 de000000
[ 83.810119] 3d40: de000000 8074bf74 a8d0ae80 806e5e78 808db9f9 a8bf3800 a8bf3858 a80a3de4
[ 83.818303] 3d60: 00000080 a89d0c00 000005dc a89d0c00 a87cb400 a8829040 a8764840 80c40b00
[ 83.826488] 3d80: 0000001c a87cb400 a87cb484 8074fd9c 0000001c a87cb400 a87cb484 8075cdfc
[ 83.834673] 3da0: 00000000 8076c4c4 a89d0c00 a8764810 a89d0c00 a8829040 a87cb400 8076d180
[ 83.842857] 3dc0: a8764828 00000007 00000000 8076e1d4 00000000 00000000 a924a900 a924a958
[ 83.851041] 3de0: 00000000 00000007 00000000 00000000 003a0000 00000000 000002ff 00000000
[ 83.859224] 3e00: 00000000 16000000 00000000 00000000 00000000 00000000 00000000 0000008f
[ 83.867409] 3e20: 00000005 00000000 a89d0c00 00000000 a924a858 00000001 a87cb400 8076ea34
[ 83.875594] 3e40: 00000001 00000000 00000004 a87cb414 ab71a3f8 a87cb448 00000101 8076e858
[ 83.883778] 3e60: 00000000 00200200 80bd0100 a87cb400 8076e858 8007b9c0 ab719380 ab719380
[ 83.891962] 3e80: a87cb448 ab719380 a80a3e98 8007bf0c ab71939c ab719b9c a80a3e98 a80a3e98
[ 83.900146] 3ea0: 00000003 000000a0 00000001 80bd0084 a80a2000 00000101 80bd0080 80bd0080
[ 83.908331] 3ec0: 40000001 80038a1c 00000000 00000001 a80a3ec8 80c51040 0000000a ffffab7f
[ 83.916514] 3ee0: 80bd0100 00200040 00000000 80bc9be4 00000000 00000010 00000000 00000001
[ 83.924699] 3f00: a80a3f50 a8008000 00000000 80038dfc 80bc9be4 8006d7c0 f4a0010c 80bd1c74
[ 83.932883] 3f20: a80a3f50 f4a00100 7a864eef 00000013 00000001 8000944c 8059b45c 000e0013
[ 83.941067] 3f40: ffffffff a80a3f84 7a864eef 80013200 a80a3f98 fffffff7 7a864eef 00000013
[ 83.949252] 3f60: ab71be90 00000000 79eea182 00000013 7a864eef 00000013 00000001 00000000
[ 83.957436] 3f80: 00000017 a80a3f98 a6aaaaab 8059b45c 000e0013 ffffffff 7a864eef 00000013
[ 83.965620] 3fa0: 80bc8320 a80a2000 80bd19e4 808288ac ab71be90 80bdab74 a80a3fc8 00000001
[ 83.973805] 3fc0: 00000000 800650ac 00000000 80bc8300 80bcae88 80bd1afc 80bd19ec 80bcba00
[ 83.981989] 3fe0: 80c4b068 80bcba00 3808406a 80c4e348 00000000 1000952c 51d97eeb 59d3c3cd
[ 83.990203] [<7f17b2c0>] (br_dev_xmit [bridge]) from [<80695bf0>] (dev_hard_start_xmit+0x248/0x30c)
[ 83.999263] [<80695bf0>] (dev_hard_start_xmit) from [<806960d8>] (__dev_queue_xmit+0x424/0x4c4)
[ 84.007975] [<806960d8>] (__dev_queue_xmit) from [<8074bf74>] (ip6_finish_output2+0x1a4/0x5b4)
[ 84.016598] [<8074bf74>] (ip6_finish_output2) from [<8074fd9c>] (ip6_output+0xb0/0x184)
[ 84.024616] [<8074fd9c>] (ip6_output) from [<8076d180>] (mld_sendpack+0x2e8/0x3d0)
[ 84.032197] [<8076d180>] (mld_sendpack) from [<8076ea34>] (mld_ifc_timer_expire+0x1dc/0x2fc)
[ 84.040652] [<8076ea34>] (mld_ifc_timer_expire) from [<8007b9c0>] (call_timer_fn+0x24/0x98)
[ 84.049015] [<8007b9c0>] (call_timer_fn) from [<8007bf0c>] (run_timer_softirq+0x1bc/0x240)
[ 84.057292] [<8007bf0c>] (run_timer_softirq) from [<80038a1c>] (__do_softirq+0x120/0x238)
[ 84.065479] [<80038a1c>] (__do_softirq) from [<80038dfc>] (irq_exit+0xc0/0xfc)
[ 84.072711] [<80038dfc>] (irq_exit) from [<8006d7c0>] (__handle_domain_irq+0x80/0xec)
[ 84.080552] [<8006d7c0>] (__handle_domain_irq) from [<8000944c>] (gic_handle_irq+0x24/0x5c)
[ 84.088913] [<8000944c>] (gic_handle_irq) from [<80013200>] (__irq_svc+0x40/0x74)
[ 84.096399] Exception stack(0xa80a3f50 to 0xa80a3f98)
[ 84.101456] 3f40: a80a3f98 fffffff7 7a864eef 00000013
[ 84.109641] 3f60: ab71be90 00000000 79eea182 00000013 7a864eef 00000013 00000001 00000000
[ 84.117825] 3f80: 00000017 a80a3f98 a6aaaaab 8059b45c 000e0013 ffffffff
[ 84.124458] [<80013200>] (__irq_svc) from [<8059b45c>] (cpuidle_enter_state+0xd8/0x20c)
[ 84.132477] [<8059b45c>] (cpuidle_enter_state) from [<800650ac>] (cpu_startup_entry+0x1fc/0x320)
[ 84.141272] [<800650ac>] (cpu_startup_entry) from [<1000952c>] (0x1000952c)
[ 84.148241] Code: e5857018 e0623003 e1c539ba eb543148 (e1d600b0)
[ 84.154369] ---[ end trace a943f7fd290272b4 ]---
[ 84.158995] Kernel panic - not syncing: Fatal exception in interrupt
[ 84.165357] CPU0: stopping
[ 84.168079] CPU: 0 PID: 0 Comm: swapper/0 Tainted: G D 4.1.15 #3
[ 84.175219] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 84.181770] [<80015d78>] (unwind_backtrace) from [<8001271c>] (show_stack+0x10/0x14)
[ 84.189529] [<8001271c>] (show_stack) from [<8081e498>] (dump_stack+0x84/0xc4)
[ 84.196763] [<8081e498>] (dump_stack) from [<80014c80>] (handle_IPI+0x178/0x18c)
[ 84.204168] [<80014c80>] (handle_IPI) from [<80009480>] (gic_handle_irq+0x58/0x5c)
[ 84.211746] [<80009480>] (gic_handle_irq) from [<80013200>] (__irq_svc+0x40/0x74)
[ 84.219233] Exception stack(0x80bcff18 to 0x80bcff60)
[ 84.224290] ff00: 80bcff60 fffffff7
[ 84.232476] ff20: 986ff11a 00000013 ab703e90 00000000 98545fd0 00000013 986ff11a 00000013
[ 84.240662] ff40: 00000001 00000000 00000017 80bcff60 a6aaaaab 8059b45c 90030013 ffffffff
[ 84.248853] [<80013200>] (__irq_svc) from [<8059b45c>] (cpuidle_enter_state+0xd8/0x20c)
[ 84.256870] [<8059b45c>] (cpuidle_enter_state) from [<800650ac>] (cpu_startup_entry+0x1fc/0x320)
[ 84.265668] [<800650ac>] (cpu_startup_entry) from [<80b5fc6c>] (start_kernel+0x39c/0x3a8)
[ 84.273851] CPU3: stopping
[ 84.276570] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G D 4.1.15 #3
[ 84.283710] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 84.290256] [<80015d78>] (unwind_backtrace) from [<8001271c>] (show_stack+0x10/0x14)
[ 84.298011] [<8001271c>] (show_stack) from [<8081e498>] (dump_stack+0x84/0xc4)
[ 84.305243] [<8081e498>] (dump_stack) from [<80014c80>] (handle_IPI+0x178/0x18c)
[ 84.312648] [<80014c80>] (handle_IPI) from [<80009480>] (gic_handle_irq+0x58/0x5c)
[ 84.320227] [<80009480>] (gic_handle_irq) from [<80013200>] (__irq_svc+0x40/0x74)
[ 84.327714] Exception stack(0xa80a5f50 to 0xa80a5f98)
[ 84.332772] 5f40: a80a5f98 fffffff7 986ff11a 00000013
[ 84.340958] 5f60: ab727e90 00000000 97c95de0 00000013 986ff11a 00000013 00000001 00000000
[ 84.349143] 5f80: 00000017 a80a5f98 a6aaaaab 8059b45c 90000013 ffffffff
[ 84.355771] [<80013200>] (__irq_svc) from [<8059b45c>] (cpuidle_enter_state+0xd8/0x20c)
[ 84.363788] [<8059b45c>] (cpuidle_enter_state) from [<800650ac>] (cpu_startup_entry+0x1fc/0x320)
[ 84.372583] [<800650ac>] (cpu_startup_entry) from [<1000952c>] (0x1000952c)
[ 84.379551] CPU1: stopping
[ 84.382270] CPU: 1 PID: 0 Comm: swapper/1 Tainted: G D 4.1.15 #3
[ 84.389409] Hardware name: Freescale i.MX6 Quad/DualLite (Device Tree)
[ 84.395954] [<80015d78>] (unwind_backtrace) from [<8001271c>] (show_stack+0x10/0x14)
[ 84.403710] [<8001271c>] (show_stack) from [<8081e498>] (dump_stack+0x84/0xc4)
[ 84.410942] [<8081e498>] (dump_stack) from [<80014c80>] (handle_IPI+0x178/0x18c)
[ 84.418346] [<80014c80>] (handle_IPI) from [<80009480>] (gic_handle_irq+0x58/0x5c)
[ 84.425924] [<80009480>] (gic_handle_irq) from [<80013200>] (__irq_svc+0x40/0x74)
[ 84.433410] Exception stack(0xa80a1f50 to 0xa80a1f98)
[ 84.438468] 1f40: a80a1f98 fffffff7 986ff11a 00000013
[ 84.446654] 1f60: ab70fe90 00000000 97c921fa 00000013 986ff11a 00000013 00000001 00000000
[ 84.454838] 1f80: 00000017 a80a1f98 a6aaaaab 8059b45c 90000013 ffffffff
[ 84.461466] [<80013200>] (__irq_svc) from [<8059b45c>] (cpuidle_enter_state+0xd8/0x20c)
[ 84.469483] [<8059b45c>] (cpuidle_enter_state) from [<800650ac>] (cpu_startup_entry+0x1fc/0x320)
[ 84.478277] [<800650ac>] (cpu_startup_entry) from [<1000952c>] (0x1000952c)
[ 84.485246] ---[ end Kernel panic - not syncing: Fatal exception in interrupt
How to solve this problem,thank you!