The 5.19 kernel backport is broken
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
The latest 5.19 backport which migrated from 22.10 to 22.04 is broken on arm64. The kernel team decided to include the following change:
5e0137612430 ("video/aperture: Disable and unregister sysfb devices via aperture helpers")
it's the change 89314ff239e1933
This change was part of a much larger series that was making sure that fb devices were properly releasing the pci resources which is necessary for proper drivers to load. Because the backport misses all those other changes it breaks PCI resource release for efifb and prevents specific drivers (e.g. vmwgfx) from being loaded. It doesn't affect many other arm64 systems because most arm64 system don't have dedicated PCI gpu's, like vmwgfx is, which is presumably why it was missed.
Without the rest of the changes in that series efifb won't release BAR 2, which results in :
vmwgfx 0000:00:0f.0 BAR 2: can't reserve [mem 0x7000000-
and a black screen on boot. Because the way drm drivers work is that first they unload the legacy fb drivers, in this case efifb, and then they continue their own initialization. In this case vmwgfx can't initialize because even though efifb has been unloaded it never released the resource at BAR 2, so vmwgfx can't claim it. Currently there's no mechanism in the kernel to reload the original generic fb driver in case the specific gpu driver fails the initialization. This results in black screen on booth with vmware hypervisor on arm64 and Ubuntu's 5.19 kernel.
To fix it either the above mentioned change needs to be backed out or the rest of the patches from that series needs to be backported as well.
---
ProblemType: Bug
ApportVersion: 2.20.11-0ubuntu82.4
Architecture: arm64
AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/by-path', '/dev/snd/
CasperMD5CheckR
DistroRelease: Ubuntu 22.04
InstallationDate: Installed on 2022-01-13 (459 days ago)
InstallationMedia: Ubuntu 22.04 LTS "Jammy Jellyfish" - Alpha arm64 (20220112)
IwConfig:
lo no wireless extensions.
ens160 no wireless extensions.
MachineType: VMware, Inc. VMware20,1
Package: linux (not installed)
ProcEnviron:
TERM=xterm-
PATH=(custom, no user)
XDG_RUNTIME_
LANG=en_US.UTF-8
SHELL=/bin/bash
ProcFB:
ProcKernelCmdLine: BOOT_IMAGE=
ProcVersionSign
RelatedPackageV
linux-
linux-
linux-firmware 20220329.
RfKill:
Tags: jammy
Uname: Linux 5.19.0-38-generic aarch64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin lxd plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 03/31/2023
dmi.bios.vendor: VMware, Inc.
dmi.bios.version: VMW201.
dmi.board.name: VBSA
dmi.board.vendor: VMware, Inc.
dmi.board.version: 1
dmi.chassis.type: 1
dmi.chassis.vendor: VMware, Inc.
dmi.chassis.
dmi.modalias: dmi:bvnVMware,
dmi.product.family: VMware
dmi.product.name: VMware20,1
dmi.product.sku: 0000000000000001
dmi.product.
dmi.sys.vendor: VMware, Inc.
This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 2016706
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.