Here has a difficult problem for me, would like anyone give some advice On a mips r3000 cpu, here has a kernel crash when doing the insmod iptable_filter, The phenomenon is same as https://dev.openwrt.org/ticket/6129 1, the FW is at openwrt versoin r23057 2, the crash occurs if insmod automatically by preinit 3, but not has crash if insmod within "failsafe mode" 4, the crash address is random in the "iptable_filter_init" progress, seems the symbol or page address invalidate and sometime may crash at any other modules, (e.g. iptable_mangle/raw, but iptable_filter module is crash every time) 5, refer from the "crash log" "Cause : 00000008", maybe is a TLB issue, but I have no idea about the debug direction I have try something as these * check the irq routine * double check file arch/mips/mm/c-r3k.c * double check file arch/mips/mm/tlb-r3k.c * try to remove the patch : target/linux/generic/patches-2.6.35/027-mips_module_reloc.patch * try to remove the patch : target/linux/generic/patches-2.6.35/028-module_exports.patch * try to remove the patch : target/linux/generic/patches-2.6.35/202-mips_mem_functions_performance.patch but all can not fix this bug next is the crash log (some printk added at sys_init_module) {{{ device eth0 entered promiscuous mode br-lan: port 1(eth0) entering forwarding state br-lan: port 1(eth0) entering forwarding state sys_init_module 2626, name: crc_ccitt sys_init_module 2636 sys_init_module 2641 sys_init_module 2626, name: slhc sys_init_module 2636 sys_init_module 2641 sys_init_module 2626, name: ppp_generic sys_init_module 2636 sys_init_module 2638 PPP generic driver version 2.4.2 sys_init_module 2641 sys_init_module 2626, name: ppp_async sys_init_module 2636 sys_init_module 2638 sys_init_module 2641 sys_init_module 2626, name: x_tables sys_init_module 2636 sys_init_module 2638 sys_init_module 2641 sys_init_module 2626, name: xt_tcpudp sys_init_module 2636 sys_init_module 2638 sys_init_module 2641 sys_init_module 2626, name: ip_tables sys_init_module 2636 sys_init_module 2638 ip_tables: (C) 2000-2006 Netfilter Core Team sys_init_module 2641 sys_init_module 2626, name: iptable_filter sys_init_module 2636 sys_init_module 2638 CPU 0 Unable to handle kernel paging request at virtual address 00000000, epc == 81a6e030, ra == 81a6e024 Oops[#1]: Cpu 0 $ 0 : 00000000 00000000 00000000 00005200 $ 4 : 000000b0 81a90000 81a9224c 000012ce $ 8 : 00000030 800042c0 00000001 00000000 $12 : 00000003 ffffffff 00000000 745f7375 $16 : 819e5200 802f3260 81a30000 81a2e174 $20 : 81a6e090 802b0000 004085c4 00000002 $24 : 00000000 81a6e000 $28 : 81a86000 81a87e30 7fbef508 81a6e024 Hi : 00000000 Lo : 000000c7 epc : 81a6e030 __this_module+0x3fea0/0x3ff00 [iptable_filter] Not tainted ra : 81a6e024 __this_module+0x3fe94/0x3ff00 [iptable_filter] Status: 1000ff04 IEp Cause : 00000008 BadVA : 00000000 PrId : 0000cf01 (rtl) Modules linked in: iptable_filter(+) ip_tables xt_tcpudp x_tables ppp_async ppp_generic slhc crc_ccitt Process insmod (pid: 282, threadinfo=81a86000, task=81a08108, tls=00000000) Stack : 802eac4c 81a2e174 802c0000 802e0000 81a2e174 802c0000 802e0000 801b0b1c 00000034 8001e944 00000001 00000000 81a2e174 802c0000 802e0000 00000000 81a6e090 801b0c94 8025148c 0000002a 0000002a c016c9e8 c016c47c 00000001 81a30000 81a6e0c0 00000310 000002f0 0000001a 00000019 1000ff01 00000001 81a2e190 80008b50 80280000 80250000 81a2e19c 802b0000 004085c4 00000002 ... Call Trace: [<81a6e030>] __this_module+0x3fea0/0x3ff00 [iptable_filter] [<81a6e024>] __this_module+0x3fe94/0x3ff00 [iptable_filter] Code: 10400018 00408021 3c0281a3 <8c43e170> 2645e120 00031827 ae030188 02202021 0c6a478e Disabling lock debugging due to kernel taint sys_init_module 2626, name: iptable_mangle sys_init_module 2636 sys_init_module 2638 }}}