With modeset=1, simpledrm is reliably disabled, instead the nvidia driver is hanging
[ 80.617590] watchdog: BUG: soft lockup - CPU#2 stuck for 26s! [Xorg:2220]
[ 80.617594] Modules linked in: snd_seq_dummy snd_hrtimer xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nf_nat_tftp nft_objref nf_conntrack_tftp bridge stp llc nft_fib_inet nft_fib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_tables ebtable_nat ebtable_broute ip6table_nat ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_mangle iptable_raw iptable_security ip_set nfnetlink ebtable_filter ebtables ip6table_filter ip6_tables iptable_filter ip_tables qrtr bnep sunrpc binfmt_misc vfat fat snd_sof_pci_intel_cnl snd_sof_intel_hda_common soundwire_intel soundwire_generic_allocation soundwire_cadence snd_sof_intel_hda snd_sof_pci snd_sof_xtensa_dsp snd_sof snd_sof_utils soundwire_bus snd_soc_skl intel_tcc_cooling x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel btusb snd_soc_hdac_hda btrtl btbcm snd_hda_ext_core btintel snd_soc_sst_ipc btmtk snd_soc_sst_dsp
[ 80.617623] kvm snd_soc_acpi_intel_match mei_wdt mei_hdcp mei_pxp ee1004 snd_soc_acpi iTCO_wdt intel_pmc_bxt snd_soc_core iTCO_vendor_support dell_rbtn intel_rapl_msr bluetooth dell_laptop dell_smm_hwmon uvcvideo snd_compress iwlmvm dell_wmi videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_common irqbypass mac80211 rapl dell_smbios ac97_bus intel_cstate libarc4 intel_uncore snd_pcm_dmaengine snd_ctl_led videodev ecdh_generic snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio mc snd_hda_codec_hdmi dcdbas dell_wmi_descriptor iwlwifi snd_hda_intel snd_intel_dspcfg dell_wmi_sysman pcspkr snd_intel_sdw_acpi intel_wmi_thunderbolt firmware_attributes_class iwlmei wmi_bmof snd_hda_codec snd_hda_core snd_hwdep snd_seq cfg80211 snd_seq_device snd_pcm rfkill thunderbolt i2c_i801 snd_timer i2c_smbus mei_me snd idma64 mei soundcore int3403_thermal dell_smo8800 processor_thermal_device_pci_legacy processor_thermal_device processor_thermal_rfim processor_thermal_mbox
[ 80.617650] processor_thermal_rapl intel_rapl_common int340x_thermal_zone intel_hid intel_soc_dts_iosf int3400_thermal sparse_keymap acpi_pad acpi_thermal_rel intel_pch_thermal zram dm_crypt nvidia_drm(POE) nvidia_modeset(POE) hid_logitech_hidpp nvidia_uvm(POE) hid_logitech_dj nvidia(POE) rtsx_pci_sdmmc mmc_core uas ucsi_acpi usb_storage hid_multitouch mxm_wmi crct10dif_pclmul crc32_pclmul crc32c_intel serio_raw nvme ghash_clmulni_intel e1000e rtsx_pci typec_ucsi nvme_core typec i2c_hid_acpi i2c_hid wmi video pinctrl_cannonlake fuse analog gameport joydev
[ 80.617668] CPU: 2 PID: 2220 Comm: Xorg Tainted: P OE 5.18.13-200.fc36.x86_64 #1
[ 80.617670] Hardware name: Dell Inc. Precision 7540/042T5V, BIOS 1.10.2 07/07/2020
[ 80.617671] RIP: 0010:_nv001523kms+0x16/0x70 [nvidia_modeset]
[ 80.617703] Code: 48 00 00 00 00 48 8b 53 28 e9 ae fd ff ff 66 0f 1f 44 00 00 41 54 55 49 89 fc 53 48 8d 5f 38 48 89 f5 48 89 df e8 2a 48 00 00 <84> c0 75 46 49 8b 54 24 40 48 39 d3 48 8b 42 18 74 17 48 39 c5 75
[ 80.617705] RSP: 0018:ffffb386c2e83a38 EFLAGS: 00000206
[ 80.617706] RAX: ffffffffc2c79900 RBX: ffffa05f8ecc1040 RCX: 0000000012fe2002
[ 80.617707] RDX: ffffa05fc874fd88 RSI: ffffa05f8ee5f808 RDI: ffffa05f8ecc1040
[ 80.617708] RBP: ffffa05f8ee5f808 R08: ffffb386c2e838d8 R09: 0000000000000001
[ 80.617709] R10: 0000000000000000 R11: 000000000000ca60 R12: ffffa05f8ecc1008
[ 80.617710] R13: ffffa05f8ee5f808 R14: 0000000000000000 R15: ffffb386c034d008
[ 80.617711] FS: 00007f5b19c1afc0(0000) GS:ffffa06ed6280000(0000) knlGS:0000000000000000
[ 80.617712] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 80.617713] CR2: 00007ffc11664000 CR3: 00000001055d4006 CR4: 00000000003706e0
[ 80.617714] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 80.617715] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[ 80.617716] Call Trace:
[ 80.617717] <TASK>
[ 80.617718] ? _nv001106kms+0xc7/0x3a0 [nvidia_modeset]
[ 80.617749] ? _nv002181kms+0x135/0x200 [nvidia_modeset]
[ 80.617771] ? _nv000516kms+0xdd/0x130 [nvidia_modeset]
[ 80.617790] ? _nv002567kms+0x26c8/0x2cd0 [nvidia_modeset]
[ 80.617811] ? __vmalloc_node_range+0x3a4/0x710
[ 80.617815] ? _copy_from_user+0x43/0x60
[ 80.617818] ? _nv000533kms+0x50/0x50 [nvidia_modeset]
[ 80.617834] ? nvKmsIoctl+0x96/0x1d0 [nvidia_modeset]
[ 80.617851] ? _raw_spin_lock_irqsave+0x23/0x50
[ 80.617853] ? nvkms_ioctl+0xdf/0x150 [nvidia_modeset]
[ 80.617870] ? nvidia_frontend_unlocked_ioctl+0x35/0x50 [nvidia]
[ 80.618127] ? __x64_sys_ioctl+0x8d/0xd0
[ 80.618130] ? do_syscall_64+0x58/0x80
[ 80.618132] ? handle_mm_fault+0xae/0x280
[ 80.618135] ? do_user_addr_fault+0x1e2/0x670
[ 80.618138] ? exc_page_fault+0x70/0x170
[ 80.618139] ? entry_SYSCALL_64_after_hwframe+0x61/0xcb
[ 80.618142] </TASK>
Seems while setting the mode on the monitor. Though I don’t really know why this is triggered by the update F35->F36 with the same kernel. Since this is a notebook, please check for a bios update.