Backtrace

BUG: kernel NULL pointer dereference, address: 00000000000007f8
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0 
Oops: 0000 [#1] SMP PTI
CPU: 6 PID: 3948 Comm: Chrome_ChildIOT Not tainted 5.8.18-100.fc31.x86_64 #1
Hardware name: Acer TravelMate X3410-M/Apus_KL, BIOS V1.01 11/07/2018
RIP: 0010:unmap_page_range+0xac/0xee0
Code: 48 d3 e0 4a 8d 14 30 48 f7 d8 48 21 c2 48 8d 42 ff 48 89 d1 48 3b 84 24 a0 00 00 00 48 8b 84 24 88 00 00 00 48 0f 43 4c 24 78 <48> 8b 38 48 c7 c0 20 05 c6 ab 48 89 4c 24 70 eb 2c 0f 1f 00 48 85
RSP: 0018:ffffadc08437bb40 EFLAGS: 00010206
RAX: 00000000000007f8 RBX: ffff88c40c1b2d48 RCX: 00007f94f2d6a000
RDX: 0000800000000000 RSI: ffff88c40c1b2d48 RDI: ffffadc08437bc88
RBP: ffffffffffffffff R08: 0000000000000000 R09: 0000000000000000
R10: 000000000014ae33 R11: 0000000000000000 R12: 0000000000000000
R13: ffffadc08437bc88 R14: 00007f94f2d62000 R15: ffffadc08437bc88
FS:  0000000000000000(0000) GS:ffff88c5ded80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000007f8 CR3: 0000000276a0a005 CR4: 00000000003606e0
Call Trace:
 unmap_vmas+0x6a/0xd0
 exit_mmap+0x97/0x170
 mmput+0x61/0x140
 do_exit+0x306/0xb80
 ? __switch_to_asm+0x36/0x70
 do_group_exit+0x3a/0xa0
 get_signal+0x172/0x900
 ? schedule_hrtimeout_range_clock+0xdc/0xf0
 ? ep_scan_ready_list.constprop.0+0x174/0x180
 do_signal+0x30/0x700
 ? ep_poll+0x23d/0x4b0
 ? finish_wait+0x80/0x80
 __prepare_exit_to_usermode+0x14a/0x1e0
 do_syscall_64+0x59/0x90
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f95084669fe
Code: Unable to access opcode bytes at RIP 0x7f95084669d4.
RSP: 002b:00007f94ef6921e0 EFLAGS: 00000293 ORIG_RAX: 00000000000000e8
RAX: fffffffffffffffc RBX: 000022640085c120 RCX: 00007f95084669fe
RDX: 0000000000000020 RSI: 0000226400273a80 RDI: 000000000000001d
RBP: 00007f94ef692240 R08: 0000000000000000 R09: 0000000000006f03
R10: 00000000ffffffff R11: 0000000000000293 R12: 0000226400288d00
R13: 0000000000000000 R14: 0000226400273a80 R15: 00002264009a0000
Modules linked in: rfcomm ccm xt_CHECKSUM xt_MASQUERADE nf_nat_tftp nf_conntrack_tftp tun bridge stp llc nf_conntrack_netbios_ns nf_conntrack_broadcast xt_CT ip6t_REJECT nf_reject_ipv6 ip6t_rpfilter ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat iptable_mangle iptable_raw iptable_security nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter cmac bnep sunrpc vfat fat squashfs loop snd_hda_codec_hdmi iwlmvm snd_soc_skl mac80211 snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi snd_hda_codec_realtek snd_soc_core snd_hda_codec_generic ledtrig_audio x86_pkg_temp_thermal intel_powerclamp coretemp libarc4 snd_compress ac97_bus snd_pcm_dmaengine kvm_intel snd_hda_intel snd_intel_dspcfg iwlwifi snd_hda_codec snd_hda_core kvm snd_hwdep iTCO_wdt ee1004 intel_pmc_bxt snd_seq
 iTCO_vendor_support intel_rapl_msr uvcvideo mei_hdcp btusb snd_seq_device btrtl irqbypass btbcm snd_pcm videobuf2_vmalloc videobuf2_memops btintel rapl videobuf2_v4l2 cfg80211 intel_cstate videobuf2_common bluetooth snd_timer intel_uncore videodev pcspkr snd acer_wmi intel_wmi_thunderbolt i2c_i801 sparse_keymap soundcore wmi_bmof i2c_smbus ecdh_generic rfkill mc ecc joydev mei_me processor_thermal_device ucsi_acpi intel_rapl_common typec_ucsi idma64 intel_pch_thermal intel_xhci_usb_role_switch mei roles intel_soc_dts_iosf typec int3403_thermal acer_wireless int340x_thermal_zone int3400_thermal acpi_thermal_rel acpi_pad ip_tables i915 i2c_algo_bit drm_kms_helper cec drm crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel r8169 serio_raw pinctrl_sunrisepoint wmi pinctrl_intel video fuse
CR2: 00000000000007f8