BUG: unable to handle kernel NULL pointer dereference at (null)

[sctb512]

During the running of the program, there will always be a null pointer exception. How can I fix this problem?

247 [ 1425.681532] BUG: unable to handle kernel NULL pointer dereference at (null)
248 [ 1425.701767] IP: [] stackbd_make_request2+0x74/0x150 [infiniswap]
249 [ 1425.722366] PGD 0
250 [ 1425.731941] Oops: 0002 [#1] SMP
251 [ 1425.742142] Modules linked in: infiniswap(OE) rdma_ucm(OE) ib_ucm(OE) rdma_cm(OE) iw_cm(OE) configfs ib_ipoib(OE) ib_cm(OE) ib_uverbs(OE) ib_umad(OE) mlx5_ib(OE) mlx5_core(OE) mlx4_ib(OE) ib_core(OE) mlx4_en(OE) mlx4_core(OE) mlx_compat(OE) veth 8021q garp mrp nfsv3 ipod(OE) ipt_MASQUERADE nf_nat_masquerade_ipv4 nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 xt_addrtype iptable_filter ip_tables xt_conntrack x_tables nf_nat nf_conntrack br_netfilter bridge stp llc overlay aufs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm ast ttm drm_kms_helper drm joydev input_leds fb_sys_fops syscopyarea sysfillrect dcdbas sysimgblt irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd ioatdma mei_me sb_edac lpc_ich mei edac_core shpchp wmi ipmi_si 8250_fintek ipmi_msghandler acpi_pad mac_hid lp parport nfsd auth_rpcgss nfs_acl nfs lockd grace sunrpc fscache hid_generic usbhid hid igb i2c_algo_bit ixgbe(OE) vxlan ip6_udp_tunnel udp_tunnel dca ahci ptp libahci pps_core fjes [last unloaded: mlx_compat]
252 [ 1426.081679] CPU: 8 PID: 11134 Comm: python3 Tainted: G OE 4.4.0-140-generic #166~14.04.1-Ubuntu
253 [ 1426.111690] Hardware name: Dell Inc. PowerEdge C6220 II/09N44V, BIOS 2.3.1 01/02/2014
254 [ 1426.132262] task: ffff880849d1aa00 ti: ffff880846f1c000 task.ti: ffff880846f1c000
255 [ 1426.152463] RIP: 0010:[] [] stackbd_make_request2+0x74/0x150 [infiniswap]
256 [ 1426.182476] RSP: 0000:ffff880846f1fb60 EFLAGS: 00010086
257 [ 1426.202285] RAX: 0000000000000000 RBX: ffff880be3321f00 RCX: 0000000000000000
258 [ 1426.231659] RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000046
259 [ 1426.251873] RBP: ffff880846f1fb70 R08: 0000000000000007 R09: 0000000002080020
260 [ 1426.272087] R10: 0000000000000000 R11: ffffffff81cd7fe8 R12: ffff880851b4d5c0
261 [ 1426.292334] R13: 000000000000000e R14: 0000000000001000 R15: ffff88084ed92cc0
262 [ 1426.312646] FS: 00007f84dc364180(0000) GS:ffff88105e600000(0000) knlGS:0000000000000000
263 [ 1426.342119] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
264 [ 1426.362056] CR2: 0000000000000000 CR3: 00000008470c0000 CR4: 0000000000160670
265 [ 1426.382240] Stack:
266 [ 1426.391847] ffff880851b4d5c0 ffff880036763000 ffff880846f1fbf8 ffffffffc0021100
267 [ 1426.412434] ffffe8fffee07800 ffff880846f1fbb0 ffffffff813b5f5f ffff880851b4d800
268 [ 1426.441635] 0000000382349000 000000000000000e 000000000000000e ffff880036763908
269 [ 1426.462237] Call Trace:
270 [ 1426.471676] [] IS_queue_rq+0x100/0x3b0 [infiniswap]
271 [ 1426.491829] [] ? part_round_stats+0x4f/0x60
272 [ 1426.511655] [] blk_mq_make_request+0x225/0x420
273 [ 1426.531656] [] generic_make_request+0xfd/0x2b0
274 [ 1426.551645] [] submit_bio+0x77/0x150
275 [ 1426.562431] [] ? end_swap_bio_write+0x80/0x80
276 [ 1426.582262] [] ? map_swap_page+0x12/0x20
277 [ 1426.602015] [] swap_readpage+0xc1/0xe0
278 [ 1426.612631] [] read_swap_cache_async+0x28/0x40
279 [ 1426.632457] [] swapin_readahead+0xfd/0x190
280 [ 1426.652428] [] handle_mm_fault+0x9a4/0x1b60
281 [ 1426.672294] [] ? __schedule+0x296/0x820
282 [ 1426.691870] [] ? __schedule+0x296/0x820
283 [ 1426.711656] [] __do_page_fault+0x19e/0x430
284 [ 1426.722431] [] do_page_fault+0x22/0x30
285 [ 1426.742059] [] page_fault+0x28/0x30
286 [ 1426.752640] Code: e9 cb 00 00 00 48 89 02 48 89 05 d8 7a 00 00 48 8b 1b 48 85 db 74 49 48 8b 15 09 6b 1d c2 be 20 00 08 02 48 89 df e8 fc 25 39 c1 <48> c7 00 00 00 00 00 48 8b 15 ae 7a 00 00 48 c7 40 48 30 06 02
287 [ 1426.822448] RIP [] stackbd_make_request2+0x74/0x150 [infiniswap]
288 [ 1426.842441] RSP
289 [ 1426.852608] CR2: 0000000000000000
290 [ 1426.874461] ---[ end trace 1887d9117942a1fc ]---
291 [ 1426.881991] ------------[ cut here ]------------
292 [ 1426.892431] WARNING: CPU: 8 PID: 11134 at /build/linux-lts-xenial-0Iypes/linux-lts-xenial-4.4.0/kernel/exit.c:661 do_exit+0x50/0xae0()
293 [ 1426.932225] Modules linked in: infiniswap(OE) rdma_ucm(OE) ib_ucm(OE) rdma_cm(OE) iw_cm(OE) configfs ib_ipoib(OE) ib_cm(OE) ib_uverbs(OE) ib_umad(OE) mlx5_ib(OE) mlx5_core(OE) mlx4_ib(OE) ib_core(OE) mlx4_en(OE) mlx4_core(OE) mlx_compat(OE) veth 8021q garp mrp nfsv3 ipod(OE) ipt_MASQUERADE nf_nat_masquerade_ipv4 nf_conntrack_netlink nfnetlink xfrm_user xfrm_algo iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 xt_addrtype iptable_filter ip_tables xt_conntrack x_tables nf_nat nf_conntrack br_netfilter bridge stp llc overlay aufs iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi ipmi_ssif x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm ast ttm drm_kms_helper drm joydev input_leds fb_sys_fops syscopyarea sysfillrect dcdbas sysimgblt irqbypass crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper cryptd ioatdma mei_me sb_edac lpc_ich mei edac_core shpchp wmi ipmi_si 8250_fintek ipmi_msghandler acpi_pad mac_hid lp parport nfsd auth_rpcgss nfs_acl nfs lockd grace sunrpc fscache hid_generic usbhid hid igb i2c_algo_bit ixgbe(OE) vxlan ip6_udp_tunnel udp_tunnel dca ahci ptp libahci pps_core fjes [last unloaded: mlx_compat]
294 [ 1427.262584] CPU: 8 PID: 11134 Comm: python3 Tainted: G D OE 4.4.0-140-generic #166~14.04.1-Ubuntu
295 [ 1427.292590] Hardware name: Dell Inc. PowerEdge C6220 II/09N44V, BIOS 2.3.1 01/02/2014
296 [ 1427.322117] 0000000000000000 ffff880846f1f880 ffffffff813e9d19 0000000000000000
297 [ 1427.342590] ffffffff81cbf198 ffff880846f1f8b8 ffffffff81082786 0000000000000009
298 [ 1427.371826] ffff880846f1fab8 0000000000000046 ffff880849d1aa00 0000000000000000
299 [ 1427.392216] Call Trace:
300 [ 1427.401760] [] dump_stack+0x63/0x8a
301 [ 1427.412545] [] warn_slowpath_common+0x86/0xc0
302 [ 1427.432196] [] warn_slowpath_null+0x1a/0x20
303 [ 1427.452162] [] do_exit+0x50/0xae0
304 [ 1427.471790] [] oops_end+0x93/0xd0
305 [ 1427.482202] [] no_context+0x10d/0x370
306 [ 1427.502159] [] __bad_area_nosemaphore+0x109/0x210
307 [ 1427.521995] [] bad_area+0x43/0x4a
308 [ 1427.541554] [] __do_page_fault+0x381/0x430
309 [ 1427.552367] [] do_page_fault+0x22/0x30
310 [ 1427.571996] [] page_fault+0x28/0x30
311 [ 1427.591565] [] ? stackbd_make_request2+0x74/0x150 [infiniswap]
312 [ 1427.611949] [] IS_queue_rq+0x100/0x3b0 [infiniswap]
313 [ 1427.631973] [] ? part_round_stats+0x4f/0x60
314 [ 1427.651578] [] blk_mq_make_request+0x225/0x420
315 [ 1427.671571] [] generic_make_request+0xfd/0x2b0
316 [ 1427.682555] [] submit_bio+0x77/0x150
317 [ 1427.702149] [] ? end_swap_bio_write+0x80/0x80
318 [ 1427.722190] [] ? map_swap_page+0x12/0x20
319 [ 1427.741585] [] swap_readpage+0xc1/0xe0
320 [ 1427.752376] [] read_swap_cache_async+0x28/0x40
321 [ 1427.772234] [] swapin_readahead+0xfd/0x190
322 [ 1427.792197] [] handle_mm_fault+0x9a4/0x1b60
323 [ 1427.811935] [] ? __schedule+0x296/0x820
324 [ 1427.831567] [] ? __schedule+0x296/0x820
325 [ 1427.842353] [] __do_page_fault+0x19e/0x430
326 [ 1427.862168] [] do_page_fault+0x22/0x30
327 [ 1427.881928] [] page_fault+0x28/0x30
328 [ 1427.901549] ---[ end trace 1887d9117942a1fd ]---