I am seeing the same bug, specifically both linux-modules-nvidia-460-generic and linux-modules-nvidia-470-generic Ubuntu packaged pre-built modules. I do not have dkms installed. These messages do not occur periodically on their own, but do seem to occur multiple times in quick succession after un-blanking and unlocking the laptop after the screen-saver has blanked the displays. I have a 2nd screen plugged in via DisplayPort. The machine is pugged into mains power and has not suspended or hibernated, between the screen locking and being unlocked a few hours later. This machine is operating in prime-select on-demand mode, with Hybrid graphics enabled in the UEFI BIOS. Log from 460 version see below for one from then 470 version. ------------[ cut here ]------------ Sep 10 22:07:08 tim-ThinkPad-P17 kernel: WARNING: CPU: 10 PID: 195514 at build/nvidia/460.91.03/build/nvidia-drm/nvidia-drm-drv.c:530 nv_drm_master_set+0x27/0x30 [nvidia_drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: Modules linked in: exfat mmc_block hid_logitech_hidpp uhid rfcomm xt_conntrack xt_MASQUERADE nf_conntrack_netlink xfrm_user xfrm_algo xt_addrtype nft_compat br_netfilter ccm nft_counter nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct bridge stp llc nft_chain_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 overlay ip_set nf_tables nfnetlink cmac algif_hash algif_skcipher af_alg bnep binfmt_misc nls_iso8859_1 nvidia_uvm(PO) nvidia_drm(PO) nvidia_modeset(PO) snd_sof_pci snd_sof_intel_hda_common snd_sof_intel_hda snd_sof_intel_byt snd_sof_intel_ipc snd_sof snd_sof_xtensa_dsp snd_soc_hdac_hda snd_hda_ext_core snd_soc_acpi_intel_match snd_soc_acpi nvidia(PO) x86_pkg_temp_thermal intel_powerclamp coretemp snd_hda_codec_hdmi kvm_intel snd_hda_codec_realtek mei_hdcp snd_hda_codec_generic intel_rapl_msr kvm iwlmvm snd_hda_intel snd_intel_dspcfg soundwire_intel soundwire_generic_allocation soundwire_cadence Sep 10 22:07:08 tim-ThinkPad-P17 kernel: crct10dif_pclmul snd_hda_codec ghash_clmulni_intel mac80211 aesni_intel snd_hda_core crypto_simd cryptd glue_helper soundwire_bus rapl btusb btrtl btbcm libarc4 snd_usb_audio uvcvideo snd_soc_core thinkpad_acpi intel_cstate btintel videobuf2_vmalloc processor_thermal_device snd_usbmidi_lib iwlwifi snd_hwdep bluetooth cdc_ether videobuf2_memops processor_thermal_rfim videobuf2_v4l2 usbnet processor_thermal_mbox efi_pstore intel_wmi_thunderbolt wmi_bmof snd_compress videobuf2_common nvram ac97_bus snd_seq_midi ledtrig_audio ee1004 r8152 snd_seq_midi_event videodev snd_rawmidi snd_pcm_dmaengine mii joydev input_leds ucsi_acpi processor_thermal_rapl mei_me intel_rapl_common mc typec_ucsi ecdh_generic cfg80211 snd_pcm ecc mei intel_soc_dts_iosf intel_pch_thermal serio_raw typec snd_seq snd_seq_device snd_timer snd soundcore int3403_thermal int340x_thermal_zone int3400_thermal mac_hid acpi_thermal_rel acpi_pad sch_fq_codel msr parport_pc ppdev lp parport ip_tables x_tables Sep 10 22:07:08 tim-ThinkPad-P17 kernel: autofs4 zfs(PO) zunicode(PO) zzstd(O) zlua(O) zavl(PO) icp(PO) zcommon(PO) znvpair(PO) spl(O) btrfs blake2b_generic xor hid_generic usbhid hid raid6_pq libcrc32c dm_mirror dm_region_hash dm_log i915 rtsx_pci_sdmmc i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops cec rc_core crc32_pclmul e1000e psmouse drm i2c_i801 i2c_smbus intel_lpss_pci thunderbolt nvme rtsx_pci intel_lpss xhci_pci idma64 nvme_core xhci_pci_renesas virt_dma wmi pinctrl_cannonlake video Sep 10 22:07:08 tim-ThinkPad-P17 kernel: CPU: 10 PID: 195514 Comm: gpu-manager Tainted: P W O 5.11.0-34-generic #36-Ubuntu Sep 10 22:07:08 tim-ThinkPad-P17 kernel: Hardware name: LENOVO 20SNCTO1WW/20SNCTO1WW, BIOS N30ET40W (1.23 ) 08/03/2021 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RIP: 0010:nv_drm_master_set+0x27/0x30 [nvidia_drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: Code: 10 94 c5 0f 1f 44 00 00 55 48 8b 47 48 48 8b 78 20 48 8b 05 db 5c 00 00 48 89 e5 48 8b 40 28 e8 0f 70 d0 c5 84 c0 74 02 5d c3 <0f> 0b 5d c3 0f 1f 44 00 00 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RSP: 0018:ffffb412d214bb80 EFLAGS: 00010246 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RAX: 0000000000000000 RBX: ffff9567cd121600 RCX: 0000000000000008 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RDX: ffffffffc1be1ed8 RSI: 0000000000000292 RDI: ffffffffc1be1ea0 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RBP: ffffb412d214bb80 R08: 0000000000000008 R09: ffffb412d214bb68 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: R10: 0000000000000000 R11: ffff9566404546da R12: ffff95699d09dc80 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: R13: ffff95664fa64800 R14: 0000000000000000 R15: ffff95664fa64800 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: FS: 00007fd6d0285b80(0000) GS:ffff956d5f680000(0000) knlGS:0000000000000000 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: CR2: 00007fd6d098d3ea CR3: 00000004ba274002 CR4: 00000000007706e0 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: PKRU: 55555554 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: Call Trace: Sep 10 22:07:08 tim-ThinkPad-P17 kernel: drm_new_set_master+0x7e/0x100 [drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: drm_master_open+0x6e/0xa0 [drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: drm_open+0xf8/0x250 [drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: drm_stub_open+0xba/0x140 [drm] Sep 10 22:07:08 tim-ThinkPad-P17 kernel: chrdev_open+0xf7/0x220 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: ? cdev_device_add+0x90/0x90 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: do_dentry_open+0x156/0x370 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: vfs_open+0x2d/0x30 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: do_open+0x1c3/0x340 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: path_openat+0x10a/0x1d0 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: do_filp_open+0x8c/0x130 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: ? __check_object_size+0x1c/0x20 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: do_sys_openat2+0x9b/0x150 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: __x64_sys_openat+0x56/0x90 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: do_syscall_64+0x38/0x90 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: entry_SYSCALL_64_after_hwframe+0x44/0xa9 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RIP: 0033:0x7fd6d071f8db Sep 10 22:07:08 tim-ThinkPad-P17 kernel: Code: 25 00 00 41 00 3d 00 00 41 00 74 4b 64 8b 04 25 18 00 00 00 85 c0 75 67 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 91 00 00 00 48 8b 4c 24 28 64 48 2b 0c 25 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RSP: 002b:00007ffd21c0d4d0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007fd6d071f8db Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RDX: 0000000000000002 RSI: 00007ffd21c0d5a0 RDI: 00000000ffffff9c Sep 10 22:07:08 tim-ThinkPad-P17 kernel: RBP: 00007ffd21c0d5a0 R08: 0000000000000000 R09: 00007ffd21c0d3e0 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Sep 10 22:07:08 tim-ThinkPad-P17 kernel: ---[ end trace cbfe24f32aba58eb ]--- with 470 installed: ------------[ cut here ]------------ Sep 08 15:37:57 tim-ThinkPad-P17 kernel: WARNING: CPU: 7 PID: 7113 at build/nvidia/470.57.02/build/nvidia-drm/nvidia-> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: Modules linked in: rfcomm hid_logitech_hidpp uhid xt_conntrack xt_MASQUERADE> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: ghash_clmulni_intel nvidia(PO) mei_hdcp intel_rapl_msr soundwire_bus mac802> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: sch_fq_codel msr parport_pc ppdev drm lp parport ip_tables x_tables autofs4> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: CPU: 7 PID: 7113 Comm: gpu-manager Tainted: P W O 5.11.0-31-gen> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: Hardware name: LENOVO 20SNCTO1WW/20SNCTO1WW, BIOS N30ET40W (1.23 ) 08/03/2021 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RIP: 0010:nv_drm_master_set+0x27/0x30 [nvidia_drm] Sep 08 15:37:57 tim-ThinkPad-P17 kernel: Code: e0 3e fa 0f 1f 44 00 00 55 48 8b 47 48 48 8b 78 20 48 8b 05 bb 6c 00 0> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RSP: 0018:ffffb113960e7b80 EFLAGS: 00010246 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RAX: 0000000000000000 RBX: ffffa04f698c6e00 RCX: 0000000000000008 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RDX: ffffffffc4c39ed8 RSI: 0000000000000292 RDI: ffffffffc4c39ea0 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RBP: ffffb113960e7b80 R08: 0000000000000008 R09: ffffb113960e7b68 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: R10: 0000000000000000 R11: ffffa04e89e7f90a R12: ffffa04ec9ce6240 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: R13: ffffa04e9a52f800 R14: 0000000000000000 R15: ffffa04e9a52f800 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: FS: 00007fb48af70b80(0000) GS:ffffa055a3bc0000(0000) knlGS:0000000000000000 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: CR2: 00007fb48b6783ea CR3: 0000000141704004 CR4: 00000000007706e0 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: PKRU: 55555554 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: Call Trace: Sep 08 15:37:57 tim-ThinkPad-P17 kernel: drm_new_set_master+0x7e/0x100 [drm] Sep 08 15:37:57 tim-ThinkPad-P17 kernel: drm_master_open+0x6e/0xa0 [drm] Sep 08 15:37:57 tim-ThinkPad-P17 kernel: drm_open+0xf8/0x250 [drm] Sep 08 15:37:57 tim-ThinkPad-P17 kernel: drm_stub_open+0xba/0x140 [drm] Sep 08 15:37:57 tim-ThinkPad-P17 kernel: chrdev_open+0xf7/0x220 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: ? cdev_device_add+0x90/0x90 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: do_dentry_open+0x156/0x370 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: vfs_open+0x2d/0x30 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: do_open+0x1c3/0x340 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: path_openat+0x10a/0x1d0 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: do_filp_open+0x8c/0x130 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: ? __check_object_size+0x1c/0x20 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: do_sys_openat2+0x9b/0x150 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: __x64_sys_openat+0x56/0x90 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: do_syscall_64+0x38/0x90 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: entry_SYSCALL_64_after_hwframe+0x44/0xa9 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RIP: 0033:0x7fb48b40a8db Sep 08 15:37:57 tim-ThinkPad-P17 kernel: Code: 25 00 00 41 00 3d 00 00 41 00 74 4b 64 8b 04 25 18 00 00 00 85 c0 75 6> Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RSP: 002b:00007ffef9bad1b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fb48b40a8db Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RDX: 0000000000000002 RSI: 00007ffef9bad280 RDI: 00000000ffffff9c Sep 08 15:37:57 tim-ThinkPad-P17 kernel: RBP: 00007ffef9bad280 R08: 0000000000000000 R09: 00007ffef9bad0c0 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Sep 08 15:37:57 tim-ThinkPad-P17 kernel: ---[ end trace 0905aff1b516ac6f ]---