On Fri, Sep 17, 2010 at 08:55:43PM +0800, arrow zhang wrote: > 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, Are you sure you really have an R3000? That's an very old processor released in 1988. > 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 That could be a fairly generic sympthom for dereferencing a bad pointer. > 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] The big difference between your issue and the old issue in openwrt is that your system dies in the kernel itself; the old openwrt case blows up while executing code of the module. So they're probably something different. (I think the openwrt issue was actually something specific to 64-bit kernels.) > 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 > }}} Ralf
