Thanks for sharing the logs. By comparing them the only relevant difference I noticed is the following one:
* In kernel 6.8.0-11 (which is the one working), the kernel attempts to load hyperv_fb, but fails: [ 29.103795] hyperv_fb: No memory for framebuffer [ 29.104204] hyperv_fb: probe of 5620e0c7-8062-4dce-aeb7-520c7ef76171 failed with error -12 This triggers the fallback to hyperv_drm, which then successfully initializes a DRM-based framebuffer: [ 29.222515] hyperv_drm 5620e0c7-8062-4dce-aeb7-520c7ef76171: [drm] fb0: hyperv_drmdrmfb frame buffer device * In kernel 6.8.0-62 (which is not working), the kernel successfully loads hyperv_fb: [ 20.738004] hyperv_fb: Synthvid Version major 3, minor 5 [ 20.738124] hyperv_fb: Screen resolution: 1024x768, Color depth: 32, Frame buffer size: 8388608 Therefore there is no hyperv_drm initialization. Thus, the system ends up using hyperv_fb exclusively, which provides only the default 1024x768 framebuffer, and does not support resolution changes, unlike hyperv_drm. This change in behavior is due to the following commit: - 20ee2ae8c589 fbdev/hyperv_fb: Fix logic error for Gen2 VMs in hvfb_getmem() which fixes the bug that makes hyperv_fb fail. Moreover, comparing Noble with Debian Unstable, I noticed that in Ubuntu's config we have: - CONFIG_FB_HYPERV=m while in Debian: - # CONFIG_FB_HYPERV is not set This is most probably the reason why screen resizing works in Debian but not on Ubuntu. To confirm this hypothesis, can you please blacklist the hyperv_fb module on Noble (6.8 or 6.11 or 6.14) and verify if the problem is still reproducible? To do this you can execute: $ echo "blacklist hyperv_fb" | sudo tee /etc/modprobe.d/blacklist-hyperv_fb.conf $ sudo update-initramfs -u $ sudo reboot Confirm that the module is indeed not loaded: $ lsmod | grep hyperv_fb $ modprobe --showconfig | grep hyperv_fb Please execute the steps above and paste here the output of the commands. Please attach also the dmesg as usual. Thanks ** Changed in: linux-meta-hwe-6.11 (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-meta-hwe-6.11 in Ubuntu. https://bugs.launchpad.net/bugs/2115068 Title: Ubuntu 24.04+ arm64: screen resolution fixed to 1024x768 with last kernel update Status in linux-meta-hwe-6.11 package in Ubuntu: Confirmed Bug description: Hi, I have a problem after a kernel update on ubuntu 24.04 arm64. In a few words up to kernel 6.8.11 everything works well and I can change the screen resolution. Starting from kernel 6.8.31 (linux-generic), I cannot do it anymore. I tried manually installing several kernels (for instance 6.8.4-060804-generic) and even linux-generic-hwe (6.11.x). I did many tests by changing the configuration and following the advice of the mate community https://ubuntu-mate.community/t/ubuntu-mate-24-04-screen-resolution-fixed-to-1024x768-with-last-kernel-update/. However, I came to the conclusions that is something related with ubuntu (gnome or mate is indifferent). Indeed, I tried with: Debian 12.11 with kernel 6.1.x and mate desktop: no problem (expected). Debian 13 daily build with kernel 6.12.x and mate desktop: no problem. Fedora 42 workstation with kernel 6.14.x and gnome desktop: no problem. Ubuntu 24.04 server with kernel 6.8.x and 6.11.x: problem (works only up to kernel 6.8.11). Ubuntu 25.04 with kernel 6.14.x and gnome desktop: problem. I have to mention that my device SoC, Qualcomm Snapdragon 8cx gen 2, is the only one in the series (gen 1, gen 3 and gen 4 https://bugzilla.kernel.org/show_bug.cgi?id=218512) that is not supported by the linux kernel. So the only solution I have found to use my device is to use hyper-v on windows 11 (virtualbox does not work on arm on windows https://www.virtualbox.org/manual/topics/Introduction.html#host-guest- matrix). Thank you --- ProblemType: Bug ApportVersion: 2.28.1-0ubuntu3.7 Architecture: arm64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/seq: test 1846 F.... pipewire CRDA: N/A CasperMD5CheckResult: pass CurrentDesktop: MATE DistroRelease: Ubuntu 24.04 InstallationDate: Installed on 2024-03-24 (456 days ago) InstallationMedia: Ubuntu 24.04 LTS "Noble Numbat" - Daily arm64 (20240324) IwConfig: lo no wireless extensions. eth0 no wireless extensions. Lspci: Lspci-vt: Lsusb: Error: command ['lsusb'] failed with exit code 1: Lsusb-t: Lsusb-v: Error: command ['lsusb', '-v'] failed with exit code 1: MachineType: Microsoft Corporation Virtual Machine Package: linux-meta-hwe-6.11 (not installed) ProcFB: 0 hyperv_drmdrmfb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-6.8.0-11-generic root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 6.8.0-11.11-generic 6.8.0-rc4 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-6.8.0-11-generic N/A linux-backports-modules-6.8.0-11-generic N/A linux-firmware 20240318.git3b128b60-0ubuntu2.13 RfKill: Tags: noble Uname: Linux 6.8.0-11-generic aarch64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo users WifiSyslog: _MarkForUpload: True dmi.bios.date: 11/21/2024 dmi.bios.release: 4.1 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v4.1 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v4.1 dmi.chassis.asset.tag: 2506-9471-9497-6998-6093-8372-56 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v4.1 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev4.1:bd11/21/2024:br4.1:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev4.1:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev4.1:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev4.1:skuNone: dmi.product.family: Virtual Machine dmi.product.name: Virtual Machine dmi.product.sku: None dmi.product.version: Hyper-V UEFI Release v4.1 dmi.sys.vendor: Microsoft Corporation --- ProblemType: Bug ApportVersion: 2.28.1-0ubuntu3.7 Architecture: arm64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/seq: test 1826 F.... pipewire CRDA: N/A CasperMD5CheckResult: pass CurrentDesktop: MATE DistroRelease: Ubuntu 24.04 InstallationDate: Installed on 2024-03-24 (456 days ago) InstallationMedia: Ubuntu 24.04 LTS "Noble Numbat" - Daily arm64 (20240324) IwConfig: lo no wireless extensions. eth0 no wireless extensions. Lspci: Lspci-vt: Lsusb: Error: command ['lsusb'] failed with exit code 1: Lsusb-t: Lsusb-v: Error: command ['lsusb', '-v'] failed with exit code 1: MachineType: Microsoft Corporation Virtual Machine Package: linux-meta-hwe-6.11 (not installed) ProcFB: 0 hyperv_fb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-6.8.0-62-generic root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 6.8.0-62.65-generic 6.8.12 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-6.8.0-62-generic N/A linux-backports-modules-6.8.0-62-generic N/A linux-firmware 20240318.git3b128b60-0ubuntu2.13 RfKill: Tags: noble Uname: Linux 6.8.0-62-generic aarch64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo users WifiSyslog: _MarkForUpload: True dmi.bios.date: 11/21/2024 dmi.bios.release: 4.1 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v4.1 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v4.1 dmi.chassis.asset.tag: 2506-9471-9497-6998-6093-8372-56 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v4.1 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev4.1:bd11/21/2024:br4.1:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev4.1:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev4.1:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev4.1:skuNone: dmi.product.family: Virtual Machine dmi.product.name: Virtual Machine dmi.product.sku: None dmi.product.version: Hyper-V UEFI Release v4.1 dmi.sys.vendor: Microsoft Corporation --- ProblemType: Bug ApportVersion: 2.28.1-0ubuntu3.7 Architecture: arm64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/seq: test 1827 F.... pipewire CRDA: N/A CasperMD5CheckResult: pass CurrentDesktop: MATE DistroRelease: Ubuntu 24.04 InstallationDate: Installed on 2024-03-24 (456 days ago) InstallationMedia: Ubuntu 24.04 LTS "Noble Numbat" - Daily arm64 (20240324) IwConfig: lo no wireless extensions. eth0 no wireless extensions. Lspci: Lspci-vt: Lsusb: Error: command ['lsusb'] failed with exit code 1: Lsusb-t: Lsusb-v: Error: command ['lsusb', '-v'] failed with exit code 1: MachineType: Microsoft Corporation Virtual Machine Package: linux-meta-hwe-6.11 (not installed) ProcFB: 0 hyperv_fb ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-6.11.0-26-generic root=/dev/mapper/ubuntu--vg-ubuntu--lv ro quiet splash vt.handoff=7 ProcVersionSignature: Ubuntu 6.11.0-26.26~24.04.1-generic 6.11.11 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No PulseAudio daemon running, or not running as session daemon. RelatedPackageVersions: linux-restricted-modules-6.11.0-26-generic N/A linux-backports-modules-6.11.0-26-generic N/A linux-firmware 20240318.git3b128b60-0ubuntu2.13 RfKill: Tags: noble Uname: Linux 6.11.0-26-generic aarch64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo users WifiSyslog: _MarkForUpload: True dmi.bios.date: 11/21/2024 dmi.bios.release: 4.1 dmi.bios.vendor: Microsoft Corporation dmi.bios.version: Hyper-V UEFI Release v4.1 dmi.board.asset.tag: None dmi.board.name: Virtual Machine dmi.board.vendor: Microsoft Corporation dmi.board.version: Hyper-V UEFI Release v4.1 dmi.chassis.asset.tag: 2506-9471-9497-6998-6093-8372-56 dmi.chassis.type: 3 dmi.chassis.vendor: Microsoft Corporation dmi.chassis.version: Hyper-V UEFI Release v4.1 dmi.modalias: dmi:bvnMicrosoftCorporation:bvrHyper-VUEFIReleasev4.1:bd11/21/2024:br4.1:svnMicrosoftCorporation:pnVirtualMachine:pvrHyper-VUEFIReleasev4.1:rvnMicrosoftCorporation:rnVirtualMachine:rvrHyper-VUEFIReleasev4.1:cvnMicrosoftCorporation:ct3:cvrHyper-VUEFIReleasev4.1:skuNone: dmi.product.family: Virtual Machine dmi.product.name: Virtual Machine dmi.product.sku: None dmi.product.version: Hyper-V UEFI Release v4.1 dmi.sys.vendor: Microsoft Corporation To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-meta-hwe-6.11/+bug/2115068/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp