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aarch64-laptops / build

Build an Linux OS based image
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KVM-enabled kernel and a couple of other questions #35

Open falkor2k15 opened 4 years ago

falkor2k15 commented 4 years ago

1) Is it possible to build a c630 image with a KVM-enabled kernel to see if virtualization works? 2) Is it possible to build Ubuntu 19.10 for c630? Will the server version work without a desktop environment? 3) Has anyone built any new preinstalls or ISO installers since Ubuntu 18.04?

rhenwood-arm commented 4 years ago

It is quite likely that you already have a kernel with KVM enabled. What you probably see the kernel declaring on boot is:

CPU: All CPU(s) started at EL1 kvm [1]: HYP mode not available

The kernel needs EL2 to enable KVM with hardware virtulization but something is occupying EL2 before the kernel starts. This is probably firmware from Qualcomm.

I'm unsure about the Ubuntu specific question. I have had success using Celliwig's installer helper: https://github.com/Celliwig/Lenovo-Yoga-c630/tree/master/install-helper I used it to run the Fedora Server 31 installer and subsequently installed Fedora Server. The kernel from that distro doesn't boot to a login prompt, and the keyboard doesn't work,,, but it's a start :)

falkor2k15 commented 4 years ago

Oh really? I heard about that problem in a mobile context - but didn't know it was a problem in the laptop world. Virtualization is out of the question then.

rhenwood-arm commented 4 years ago

Not strictly accurate: You can still run VMs in QEMU user mode - but performance will be very slow.

I believe the 8CX platform has EL2 available to the kernel -- but I haven't had this confirmed yet.

woachk commented 4 years ago

Hello,

On 850 onwards, EL2 is accessible to software. However, it's done over an undocumented TrustZone dance instead of the UEFI running in EL2.