There is a new driver 450.66 available, and details are here:  https://www.nvidia.com/Download/driverResults.aspx/163238/en-us

No patch – yet – and there is an issue with the old ‘GPL block’ again..  https://gitlab.com/EULA/snippets/-/commit/9c295c9b9b9453de00941a5c84cb3c9385eafe6e

I had just tested the latest version of the 5.9 patch for NVIDIA driver 450.57, and it compiled OK, but loading was problem, and the mouse ‘wobbled’ all over the screen..  Obsolete info now, but may be useful..:

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WARNING: CPU: 3 PID: 30434 at /home/rgadsdon/NVIDIA-Linux-x86_64-450.57-custom/kernel/nvidia-drm/nvidia-drm-gem.c:52 nv_drm_gem_free+0x33/0x40 [nvidia_drm]
Modules linked in: hid_logitech_hidpp rfcomm cmac joydev bnep btusb btrtl btbcm btintel bluetooth ecdh_generic ecc cp210x hid_logitech_dj ftdi_sio nvidia_drm(PO) nvidia_modeset(PO) drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec drm nvidia(PO) vmnet(O) vmw_vsock_vmci_transport vsock vmw_vmci vmmon(O) sunrpc snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_intel kvm_intel snd_intel_dspcfg snd_hda_codec kvm snd_hda_core irqbypass snd_hwdep at24 snd_seq hp_wmi snd_seq_device rapl sparse_keymap iTCO_wdt rfkill iTCO_vendor_support snd_pcm wmi_bmof intel_cstate intel_uncore i2c_i801 snd_timer snd i2c_smbus pcspkr soundcore lpc_ich wmi crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel e1000e fuse [last unloaded: syscopyarea]
CPU: 3 PID: 30434 Comm: Xorg Tainted: P O 5.9.0-rc1 #1
Hardware name: Hewlett-Packard HP Z220 CMT Workstation/1790, BIOS K51 v01.87 06/10/2019
RIP: 0010:nv_drm_gem_free+0x33/0x40 [nvidia_drm]
Code: 8d b8 88 00 00 00 e8 6c f6 c3 ed 84 c0 74 1b 48 89 ef e8 b0 dd 41 00 48 8b 85 50 01 00 00 48 89 ef 5d 48 8b 00 e9 1d ae 55 ee <0f> 0b eb e1 66 0f 1f 84 00 00 00 00 00 55 48 89 f5 48 83 ec 08 48
RSP: 0018:ffffa718c052bd80 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8b350bb01000 RCX: 0000000000000000
RDX: ffff8b343c5ba7c0 RSI: 0000000000000000 RDI: ffff8b34edcbe088
RBP: ffff8b350bb00e00 R08: ffff8b350bb00ec8 R09: 0000000000000000
R10: ffff8b34bca9eb00 R11: ffffa718c052bd80 R12: ffff8b350bb01000
R13: ffff8b350bb01128 R14: ffff8b350bb01050 R15: ffff8b350bb01000
FS: 00007f4d55d5bf00(0000) GS:ffff8b350dcc0000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4d5498d34d CR3: 000000033aea8002 CR4: 00000000001706e0
Call Trace:
drm_gem_object_release_handle+0x6b/0x90 [drm]
? drm_mode_destroy_dumb+0x40/0x40 [drm]
drm_gem_handle_delete+0x4a/0x80 [drm]
? drm_mode_destroy_dumb+0x40/0x40 [drm]
drm_ioctl_kernel+0x82/0xd0 [drm]
drm_ioctl+0x1ff/0x390 [drm]
? drm_mode_destroy_dumb+0x40/0x40 [drm]
? kmem_cache_free+0xe8/0x1f0
__x64_sys_ioctl+0x7e/0xb0
do_syscall_64+0x33/0x80
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f4d561e73bb
Code: 0f 1e fa 48 8b 05 dd aa 0c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d ad aa 0c 00 f7 d8 64 89 01 48
RSP: 002b:00007fff65033388 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fff650333c4 RCX: 00007f4d561e73bb
RDX: 00007fff650333c4 RSI: 00000000c00464b4 RDI: 000000000000000d
RBP: 00000000c00464b4 R08: 0000000000000020 R09: 0000000000000100
R10: 00007f4d55c6fca0 R11: 0000000000000246 R12: 000000000000000d
R13: 000000000000000d R14: 000055ac8e591290 R15: 000055ac8e592080
---[ end trace 5cead1b397e40c21 ]---

More testing, when a 450.66 patch is available!

Robert Gadsdon.   August 19th 2020.