Public bug reported: with the new kernel 28 my backlight max value is 1023, instead of 12000, with the 27 it was ok. I need to add i915.enable_dpcd_backlight=0 to make it boot correctly.
ProblemType: Bug DistroRelease: Ubuntu 26.04 Package: linux-image-7.0.0-28-generic 7.0.0-28.28 ProcVersionSignature: Ubuntu 7.0.0-28.28-generic 7.0.12 Uname: Linux 7.0.0-28-generic x86_64 ApportVersion: 2.34.0-0ubuntu2 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: ypeyrota 6810 F.... wireplumber /dev/snd/controlC0: ypeyrota 6810 F.... wireplumber /dev/snd/seq: ypeyrota 6792 F.... pipewire CasperMD5CheckResult: unknown CurrentDesktop: ubuntu:GNOME Date: Wed Jul 22 14:36:06 2026 DistributionChannelDescriptor: # This is the distribution channel descriptor for the OEM CDs # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor canonical-oem-somerville-bionic-amd64-20180608-47+vulcan+X69 InstallationDate: Installed on 2019-12-24 (2402 days ago) InstallationMedia: Ubuntu 18.04 "Bionic" - Build amd64 LIVE Binary 20180608-09:38 IwDevWlo1Link: Not connected. MachineType: Dell Inc. G5 5590 ProcEnviron: LANG=fr_FR.UTF-8 PATH=(custom, no user) SHELL=/bin/bash TERM=xterm-256color XDG_RUNTIME_DIR=<set> ProcFB: 0 i915drmfb 1 nvidia-drmdrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-28-generic root=UUID=600bedd1-7d47-432e-8a5f-248cf2d8ba4b ro mitigations=off mem_sleep_default=deep quiet splash noibrs noibpb nopti nospectre_v2 nospectre_v1 l1tf=off nospec_store_bypass_disable no_stf_barrier mds=off mitigations=off i915.enable_dpcd_backlight=0 crashkernel=2G-4G:320M,4G-32G:512M,32G-64G:1024M,64G-128G:2048M,128G-:4096M SourcePackage: linux UpgradeStatus: Upgraded to resolute on 2026-05-20 (63 days ago) WifiSyslog: dmi.bios.date: 08/22/2019 dmi.bios.release: 1.10 dmi.bios.vendor: Dell Inc. dmi.bios.version: 1.10.0 dmi.board.name: 0CNDTP dmi.board.vendor: Dell Inc. dmi.board.version: A01 dmi.chassis.type: 10 dmi.chassis.vendor: Dell Inc. dmi.modalias: dmi:bvnDellInc.:bvr1.10.0:bd08/22/2019:br1.10:svnDellInc.:pnG55590:pvr:rvnDellInc.:rn0CNDTP:rvrA01:cvnDellInc.:ct10:cvr:sku08EA:pfaGSeries: dmi.product.family: GSeries dmi.product.name: G5 5590 dmi.product.sku: 08EA dmi.sys.vendor: Dell Inc. ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug resolute wayland-session -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2161514 Title: Backlight problem on dell laptop To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2161514/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
