nvidia: module verification failed: signature and/or required key missing - tainting kernel

[ 2.339868] nvidia: loading out-of-tree module taints kernel.
[ 2.339881] nvidia: module license 'NVIDIA' taints kernel.
[ 2.339882] Disabling lock debugging due to kernel taint
[ 2.344554] usb 1-3: new high-speed USB device number 3 using xhci_hcd
[ 2.354676] nvidia: module verification failed: signature and/or required key missing - tainting kernel
[ 2.368949] nvidia-nvlink: Nvlink Core is being initialized, major device number 239
[ 2.369522] nvidia 0000:01:00.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=none:owns=io+mem
[ 2.369735] NVRM: loading NVIDIA UNIX x86_64 Kernel Module 390.87 Tue Aug 21 12:33:05 PDT 2018 (using threaded interrupts)
[ 2.386968] PKCS#7 signature not signed with a trusted key
[ 2.390444] nvidia-modeset: Loading NVIDIA Kernel Mode Setting Driver for UNIX platforms 390.87 Tue Aug 21 16:16:14 PDT 2018
[ 2.391646] PKCS#7 signature not signed with a trusted key
[ 2.394094] [drm] [nvidia-drm] [GPU ID 0x00000100] Loading driver
[ 2.394098] [drm] Initialized nvidia-drm 0.0.0 20160202 for 0000:01:00.0 on minor 0

cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 55
model name : Intel(R) Pentium(R) CPU J2900 @ 2.41GHz
stepping : 8
microcode : 0x837
cpu MHz : 1332.996
cache size : 1024 KB
physical id : 0
siblings : 4
core id : 0
cpu cores : 4
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer rdrand lahf_lm 3dnowprefetch epb pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms dtherm ida arat
bugs : cpu_meltdown spectre_v1 spectre_v2
bogomips : 4831.40
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:

processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 55
model name : Intel(R) Pentium(R) CPU J2900 @ 2.41GHz
stepping : 8
microcode : 0x837
cpu MHz : 1332.896
cache size : 1024 KB
physical id : 0
siblings : 4
core id : 1
cpu cores : 4
apicid : 2
initial apicid : 2
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer rdrand lahf_lm 3dnowprefetch epb pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms dtherm ida arat
bugs : cpu_meltdown spectre_v1 spectre_v2
bogomips : 4831.40
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:

processor : 2
vendor_id : GenuineIntel
cpu family : 6
model : 55
model name : Intel(R) Pentium(R) CPU J2900 @ 2.41GHz
stepping : 8
microcode : 0x837
cpu MHz : 1332.828
cache size : 1024 KB
physical id : 0
siblings : 4
core id : 2
cpu cores : 4
apicid : 4
initial apicid : 4
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer rdrand lahf_lm 3dnowprefetch epb pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms dtherm ida arat
bugs : cpu_meltdown spectre_v1 spectre_v2
bogomips : 4831.40
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:

processor : 3
vendor_id : GenuineIntel
cpu family : 6
model : 55
model name : Intel(R) Pentium(R) CPU J2900 @ 2.41GHz
stepping : 8
microcode : 0x837
cpu MHz : 1332.808
cache size : 1024 KB
physical id : 0
siblings : 4
core id : 3
cpu cores : 4
apicid : 6
initial apicid : 6
fpu : yes
fpu_exception : yes
cpuid level : 11
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology tsc_reliable nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm sse4_1 sse4_2 movbe popcnt tsc_deadline_timer rdrand lahf_lm 3dnowprefetch epb pti ibrs ibpb stibp tpr_shadow vnmi flexpriority ept vpid tsc_adjust smep erms dtherm ida arat
bugs : cpu_meltdown spectre_v1 spectre_v2
bogomips : 4831.40
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:

kernel
4.18.0-11-generic

lspci
00:00.0 Host bridge [0600]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series SoC Transaction Register [8086:0f00] (rev 0e)
        Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series SoC Transaction Register [1043:8534]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap- 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Kernel driver in use: iosf_mbi_pci

00:13.0 SATA controller [0106]: Intel Corporation Atom Processor E3800 Series SATA AHCI Controller [8086:0f23] (rev 0e) (prog-if 01 [AHCI 1.0])
        Subsystem: ASUSTeK Computer Inc. Atom Processor E3800 Series SATA AHCI Controller [1043:8534]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Interrupt: pin A routed to IRQ 88
        Region 0: I/O ports at f070 [size=8]
        Region 1: I/O ports at f060 [size=4]
        Region 2: I/O ports at f050 [size=8]
        Region 3: I/O ports at f040 [size=4]
        Region 4: I/O ports at f020 [size=32]
        Region 5: Memory at ab415000 (32-bit, non-prefetchable) [size=2K]
        Capabilities: <access denied>
        Kernel driver in use: ahci
        Kernel modules: ahci

00:14.0 USB controller [0c03]: Intel Corporation Atom Processor Z36xxx/Z37xxx, Celeron N2000 Series USB xHCI [8086:0f35] (rev 0e) (prog-if 30 [XHCI])
        Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx, Celeron N2000 Series USB xHCI [1043:8534]
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Interrupt: pin A routed to IRQ 87
        Region 0: Memory at ab400000 (64-bit, non-prefetchable) [size=64K]
        Capabilities: <access denied>
        Kernel driver in use: xhci_hcd

00:1a.0 Encryption controller [1080]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Trusted Execution Engine [8086:0f18] (rev 0e)
        Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series Trusted Execution Engine [1043:8534]
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 90
        Region 0: Memory at ab200000 (32-bit, non-prefetchable) [size=1M]
        Region 1: Memory at ab100000 (32-bit, non-prefetchable) [size=1M]
        Capabilities: <access denied>
        Kernel driver in use: mei_txe
        Kernel modules: mei_txe

00:1b.0 Audio device [0403]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series High Definition Audio Controller [8086:0f04] (rev 0e)
        Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series High Definition Audio Controller [1043:8693]
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 92
        Region 0: Memory at ab410000 (64-bit, non-prefetchable) [size=16K]
        Capabilities: <access denied>
        Kernel driver in use: snd_hda_intel
        Kernel modules: snd_hda_intel

00:1c.0 PCI bridge [0604]: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 1 [8086:0f48] (rev 0e) (prog-if 00 [Normal decode])
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 16
        Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
        I/O behind bridge: 0000e000-0000efff
        Memory behind bridge: a0000000-ab0fffff
        Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
        BridgeCtl: Parity- SERR- NoISA- VGA+ MAbort- >Reset- FastB2B-
                PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
        Capabilities: <access denied>
        Kernel driver in use: pcieport

00:1c.2 PCI bridge [0604]: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 3 [8086:0f4c] (rev 0e) (prog-if 00 [Normal decode])
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin C routed to IRQ 18
        Bus: primary=00, secondary=02, subordinate=02, sec-latency=0
        I/O behind bridge: 0000d000-0000dfff
        Memory behind bridge: ab300000-ab3fffff
        Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
        BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
                PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
        Capabilities: <access denied>
        Kernel driver in use: pcieport

00:1c.3 PCI bridge [0604]: Intel Corporation Atom Processor E3800 Series PCI Express Root Port 4 [8086:0f4e] (rev 0e) (prog-if 00 [Normal decode])
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin D routed to IRQ 19
        Bus: primary=00, secondary=03, subordinate=03, sec-latency=0
        I/O behind bridge: 00001000-00001fff
        Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort+ <SERR- <PERR-
        BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
                PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
        Capabilities: <access denied>
        Kernel driver in use: pcieport

00:1f.0 ISA bridge [0601]: Intel Corporation Atom Processor Z36xxx/Z37xxx Series Power Control Unit [8086:0f1c] (rev 0e)
        Subsystem: ASUSTeK Computer Inc. Atom Processor Z36xxx/Z37xxx Series Power Control Unit [1043:8534]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Capabilities: <access denied>
        Kernel driver in use: lpc_ich
        Kernel modules: lpc_ich

00:1f.3 SMBus [0c05]: Intel Corporation Atom Processor E3800 Series SMBus Controller [8086:0f12] (rev 0e)
        Subsystem: ASUSTeK Computer Inc. Atom Processor E3800 Series SMBus Controller [1043:8534]
        Control: I/O+ Mem+ BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Interrupt: pin B routed to IRQ 18
        Region 0: Memory at ab414000 (32-bit, non-prefetchable) [size=32]
        Region 4: I/O ports at f000 [size=32]
        Capabilities: <access denied>
        Kernel driver in use: i801_smbus
        Kernel modules: i2c_i801

01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GK208B [GeForce GT 720] [10de:1288] (rev a1) (prog-if 00 [VGA controller])
        Subsystem: ASUSTeK Computer Inc. GK208B [GeForce GT 720] [1043:8670]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0
        Interrupt: pin A routed to IRQ 91
        Region 0: Memory at aa000000 (32-bit, non-prefetchable) [size=16M]
        Region 1: Memory at a0000000 (64-bit, prefetchable) [size=128M]
        Region 3: Memory at a8000000 (64-bit, prefetchable) [size=32M]
        Region 5: I/O ports at e000 [size=128]
        [virtual] Expansion ROM at ab000000 [disabled] [size=512K]
        Capabilities: <access denied>
        Kernel driver in use: nvidia
        Kernel modules: nvidiafb, nouveau, nvidia_drm, nvidia

01:00.1 Audio device [0403]: NVIDIA Corporation GK208 HDMI/DP Audio Controller [10de:0e0f] (rev a1)
        Subsystem: ASUSTeK Computer Inc. GK208 HDMI/DP Audio Controller [1043:8670]
        Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx-
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin B routed to IRQ 17
        Region 0: Memory at ab080000 (32-bit, non-prefetchable) [size=16K]
        Capabilities: <access denied>
        Kernel driver in use: snd_hda_intel
        Kernel modules: snd_hda_intel

02:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [10ec:8168] (rev 11)
        Subsystem: ASUSTeK Computer Inc. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller [1043:859e]
        Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
        Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
        Latency: 0, Cache Line Size: 64 bytes
        Interrupt: pin A routed to IRQ 89
        Region 0: I/O ports at d000 [size=256]
        Region 2: Memory at ab304000 (64-bit, non-prefetchable) [size=4K]
        Region 4: Memory at ab300000 (64-bit, prefetchable) [size=16K]
        Capabilities: <access denied>
        Kernel driver in use: r8169
        Kernel modules: r8169
Ubuntu 18.10