kernel crash when copying files to exfat format flash device

[Kenny0793]

Hi, It is hard to reproduce, Do you know what the issue is? Should I how to debug it? Thanks.

 [746715.230151] Unable to handle kernel paging request at virtual address 00740070

[746715.238475] pgd = 80003000 [746715.241295] [00740070] pgd=80000000004003, pmd=00000000 [746715.246865] Internal error: Oops: 80000206 [#1] SMP ARM [746715.253478] Modules linked in: dhd(O) wl(PO) igs(PO) emf(PO) hnd(O) wlcsm(PO) ebt_dhcpv6snoop ebt_dhcpsnoop ebt_dhcpsnoop_db nf_nat_pptp nf_nat_proto_gre nf_conntrack_pptp nf_conntrack_proto_gre flowmgr_rfap(PO) dqnet rdpa(PO) dqnet_rfap(PO) cifs_server(O) rdpa_helper_gpl(PO) rdpa_gpl(O) rdpa_cm(O) drv_gpio(O) hard_watchdog(PO) bsp_gpio_data(PO) bsp_gpio_lkm(O) flowmgr bdmf(O) sgmiiplus2 mdio_bcm_unimac ethsw bcm8488x [last unloaded: nf_conntrack_proto_esp] [746715.294510] CPU: 1 PID: 21945 Comm: kworker/1:2 Tainted: P O 4.9.198-Prod_20.2 #2 [746715.303218] Hardware name: Broadcom STB (Flattened Device Tree) [746715.309244] Workqueue: events handle_cifsd_work [cifs_server] [746715.315096] task: 9ef9dd80 task.stack: 97cb0000 [746715.319718] PC is at 0x740070 [746715.322779] LR is at nls_cstring_to_uniname+0x1c4/0x288 [746715.328096] pc : [<00740070>] lr : [<8040ceb4>] psr: 600e0013 [746715.328096] sp : 97cb3928 ip : 00000011 fp : 00000000 [746715.339759] r10: 00650043 r9 : 00000000 r8 : 9844e000 [746715.345084] r7 : 98689e88 r6 : 98689e01 r5 : 00000001 r4 : 00000004 [746715.351719] r3 : 000409c6 r2 : 000409c6 r1 : 00000000 r0 : 00000000 [746715.358350] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [746715.365587] Control: 30c5387d Table: 185b5f40 DAC: 55555555 [746715.371430] Process kworker/1:2 (pid: 21945, stack limit = 0x97cb0210) [746715.378051] Stack: (0x97cb3928 to 0x97cb4000) [746715.382501] 3920: 00660069 00630069 00640061 0020006f 006e0049 00650074 [746715.390775] 3940: 00760072 006e0065 00690063 00000000 00000094 000000b6 9844e0fc 00000021 [746715.399049] 3960: 00000000 00000000 9840d400 2e74c558 00000000 00000000 00000000 98689e88 [746715.407322] 3980: 8003c0b6 a0d87800 a0d878f0 000000b6 000000f0 00000000 9e8d8000 000409c6 [746715.415595] 39a0: 97cb39ac 98689e88 00000000 9e8d8000 81006408 000000b6 00000000 00000000 [746715.423868] 39c0: 9d569500 807c9488 00000000 00000000 00000000 81090538 8109054c 81007710 [746715.432141] 39e0: 81004d00 9e8d8054 8100643c 97cb3a18 00000000 00000001 00000000 9a806000 [746715.440414] 3a00: 81006408 9d569500 9a806090 98689e88 9e8d8000 807edba0 00000000 000409c6 [746715.448687] 3a20: 00000025 c142a06a 00000000 9a806000 81006408 c1429fb4 00000000 00000000 [746715.456960] 3a40: 00000000 807c99cc 9a806090 00000001 9e8d8000 00000000 c1429fb4 00000000 [746715.465232] 3a60: 000000b6 00000000 ad406100 00000000 00000000 98689e88 81006408 9844e0da [746715.473504] 3a80: 9dac0000 000409c6 9db50900 98689e88 98689e88 81074ec0 00000000 9844e0da [746715.481777] 3aa0: 9dac0000 00000000 9db50900 808fe460 000409c6 81006408 98689e88 81074ec0 [746715.490049] 3ac0: 00000000 808fe5b8 00000004 80000000 97cb3a07 00000000 9e8d8000 00000000 [746715.498322] 3ae0: 81074ec0 9efdd0c0 808fe3ac 000409c6 9ea73900 98689e88 81006408 9efdd080 [746715.506595] 3b00: 00000000 808fe6dc 00000003 80000000 97cb3b07 00000000 9e8d8000 00000000 [746715.514868] 3b20: 81000000 000409c6 808fe508 99592078 9849808c 81006408 9a7486e8 9840d400 [746715.523141] 3b40: 99592078 97cb3c70 00000000 8040ae18 97cb3b80 9a748714 995aa880 9a7486e8 [746715.531413] 3b60: 81006408 804093c8 9a7486e8 995aa880 81004ec0 97cb3c70 810c4e5c 80343d24 [746715.539687] 3b80: 97cb3c68 81006408 97cb3c70 00000230 80247be4 97cb3bf0 810c459c 97cb0000 [746715.547959] 3ba0: 9ea73910 80335adc 81006408 9e5fc6b8 9e56ef68 00080040 00000000 00000001 [746715.556232] 3bc0: 97cb3c68 000409c6 97cb3c68 9a7486e8 81006408 99592078 995920e8 995aa880 [746715.564505] 3be0: 00000001 97cb3c70 00000000 803351e8 00000000 97cb3bf4 97cb3bf4 000409c6 [746715.572778] 3c00: 9f67c01a 97cb3c68 81006408 00000000 00000001 97cb3e2c 81006408 985db800 [746715.581050] 3c20: 985dd280 80337a84 0a00a8c0 000409c6 0000002f 97cb3c68 9f67c000 000409c6 [746715.589322] 3c40: 97cb3c68 00000000 97cb3e2c 00000001 97cb3e2c 8033817c 81006408 9f67c000 [746715.597595] 3c60: 9a8f8000 80339dac 98624610 995aa880 00b71c2d 0000001f 9f67c01a 00000000 [746715.605868] 3c80: 9ea8bc10 9e5137f8 99592078 00000001 00000001 0000a516 00000000 00000000 [746715.614141] 3ca0: 00000001 97cb3ca8 9ea8bc10 9e5f34c8 00000000 00000001 9f67c015 00000002 [746715.622413] 3cc0: 00000000 00000000 00000000 00000000 000003fc 00000061 9f67c000 00000000 [746715.630685] 3ce0: 9e5fc6b8 00000002 ffffff9c 9f67c010 9f67c000 000409c6 97cb3e2c 00000001 [746715.638958] 3d00: 9a8f8000 7f111c08 97cb3e2c 80339e4c 00000000 80255fe8 02080020 9d4d2c00 [746715.647232] 3d20: 00000001 7f0de050 80e7b040 810068a4 00000020 9a8f88b8 00000001 97cb3e2c [746715.655504] 3d40: 9a8f88b8 9a8f8800 0000001f 7f0d722c 985db49f 80323188 0000001f 00000001 [746715.663777] 3d60: 00000009 985db800 985db480 0000001f 985dd280 985db80a 00000009 000409c6 [746715.672050] 3d80: 985db480 9d4d2c00 81006408 9a8f8000 7f111c08 97cb3e2c 001f01ff 9aa5e800 [746715.680322] 3da0: 985dd280 7f0ec90c 2de5921c 0002a722 9f433e40 2c7d6843 00000000 9a8f8800 [746715.688595] 3dc0: 00000000 80256c88 9a8f8000 9dbc7e80 985db800 9a886b00 00000000 97cb3e8c [746715.696867] 3de0: 000005b4 00000009 7f111b50 00000000 000011a6 00000000 97cb3e2c 9fbcc078 [746715.705140] 3e00: 001f01ff 00002409 97cb0000 00000000 9ef9dd80 9fbcc040 9ef9dd80 00000000 [746715.713412] 3e20: 00000000 00000000 00000001 9ef9de00 00000001 00000000 00000000 00000000 [746715.721684] 3e40: 00000000 00000000 00000000 00000000 80e75480 81006408 eb6927c4 80e7b040 [746715.729957] 3e60: 00000001 9fbcc078 80e7b040 00000000 9ef9de00 00000001 00000000 810068a4 [746715.738229] 3e80: 9ef9dd80 80245628 00000000 8032333c 80202b2c 9e929b80 000001c0 9d4d2c00 [746715.746501] 3ea0: 000001c0 000409c6 9d4d2c00 9aa5e800 00000005 9fbcbc40 9d4d2c00 9aa5e814 [746715.754774] 3ec0: 7f1111a4 9d4d2c60 7f111bdc 7f0e6ab0 9f432900 00000000 9aa45500 9d4d2c60 [746715.763046] 3ee0: 9aa45500 9fbcbc40 97cb0030 9fbcf500 00000000 00000000 8108dcd4 80237254 [746715.771318] 3f00: 9fbcbc40 9fbcbc40 97cb0030 9aa45500 9fbcbc40 9fbcbc58 97cb0030 8108d8ba [746715.779590] 3f20: 9aa45518 81004d00 00000008 80237594 8023754c 97cb0000 9fbcbc88 81004d00 [746715.787863] 3f40: 8023754c 9a863480 00000000 9aa45500 8023754c 00000000 00000000 00000000 [746715.796137] 3f60: 00000000 8023cb8c 00000000 9ef99b80 9aa45500 00000000 00000000 97cb3f7c [746715.804409] 3f80: 97cb3f7c 00000000 00000000 97cb3f8c 97cb3f8c 000409c6 97cb3fac 9a863480 [746715.812682] 3fa0: 8023ca9c 00000000 00000000 80208400 00000000 00000000 00000000 00000000 [746715.820954] 3fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 [746715.829226] 3fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 [746715.837507] [<8040ceb4>] (nls_cstring_to_uniname) from [<995aa880>] (0x995aa880) [746715.845001] Code: bad PC value