enabling CONFIG_KVM instead of enabling KVM via the dtb overlay will hard-disable all video acceleration of the upstream proprietary driver of the pi and make it completely unusable for any kind of setup that uses any upstram acceleration features from the raspberry pi foundation (i.e. via /opt/vc4 libs).
the proper way to enable KVM support on any pi is to set: dtoverlay=vc4-kms-v3d in the config.txt file of the bootloader, the kernel is specifically set up for this via the included raspberry pi foundation patches. this might be pointless on arm64 which is not supported at all upstream by the raspberry pi foundation (beyond offering completely unsupported 64bit binaries for for developer tinkering) and thus does not offer any video acceleration via the proprietary driver anyway on this architecture. but enabling CONFIG_KVM hardcoded in the kernel config for armhf will be fatal, please make sure this does not happen so users can still use vc4 accelerated video playback by manipulating the upstream-documented dtoverlay values on armhf builds. -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-raspi2 in Ubuntu. https://bugs.launchpad.net/bugs/1783961 Title: CONFIG_KVM is disabled for linux-raspi2 (aarch64) Status in linux-raspi2 package in Ubuntu: Confirmed Bug description: In contrast to the Linux kernel for x86_64, the CONFIG_KVM option is disabled for the "linux-raspi2" kernel (version 4.15.0-1016-raspi2 aarch64) on Ubuntu 18.04. This prevents running QEMU with the -enable-kvm option to use hardware virtualization capabilities of the CPU. I have recompiled the kernel with CONFIG_KVM set and could successfully run QEMU with -enable-kvm on my Raspberry Pi 3 B+ afterwards. In my opinion, there is no reason for not activating CONFIG_KVM in the official raspi2 kernel. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-raspi2/+bug/1783961/+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
