llvmpipe i386 crashes when running on qemu64 cpu
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
QEMU |
Expired
|
Undecided
|
Unassigned | ||
llvm-toolchain-3.6 (Ubuntu) |
Won't Fix
|
Undecided
|
Unassigned | ||
qemu (Ubuntu) |
Won't Fix
|
Medium
|
Unassigned |
Bug Description
STEPS TO REPRODUCE:
1. Install Ubuntu 14.04.2 LTS or Ubuntu 14.10 or Ubuntu 15.04 with all updates (it is a host system).
2. Download one (or all) isos:
* Ubuntu 14.0.4.2 i386 iso (ubuntu-
* Ubuntu 14.10 i386 iso (ubuntu-
* Ubuntu 15.04 i386 iso (ubuntu-
3. Boot one (or all) isos with as QEMU-KVM guest with the following commands:
* sudo kvm -m 1536 -cdrom ubuntu-
* sudo kvm -m 1536 -cdrom ubuntu-
* sudo kvm -m 1536 -cdrom ubuntu-
* or from usb-creator-gtk via "Test disk" button
4. Click on "Try Ubuntu"
EXPECTED RESULTS:
ISO is booted to Unity desktop, user can test and use it.
ACTUAL RESULTS:
In 14.04 and 14.10 guests can see empty purple desktop or purple desktop with two shortcuts ("Examples" and "Install Ubuntu ...").
15.10 guest does not boot or boot to safe graphic mode (it is bug 1437740).
The reason for this is that unity requires gfx acceleration which is done via llvmpipe on non accelerated gfx chipsets (as VMs use by default). The error message is hidden away but is:
LLVM ERROR: Do not know how to split the result of this operator!
The cause is that KVM VMs by default use the qemu64 cpu model which seems to be inconsistent in some way between claimed features and actual results when using those features. A work-around for running i386 isos is to use a cpu model like core2duo or kvm64.
This bug should be confirmed and fixed.
Users may want to run Ubuntu in QEMU/KVM, not just VirtualBox.
summary: |
- Ubuntu 14.04 guest does not boot to Unity from QEMU-KVM Ubuntu 14.04 - host + Ubuntu 14.04 LTS, 14.10, 15.04 guests do not boot to Unity from QEMU-KVM + Ubuntu 14.04 LTS host |
description: | updated |
tags: |
added: utopic vivid removed: amd64 |
summary: |
Ubuntu 14.04 LTS, 14.10, 15.04 guests do not boot to Unity from QEMU-KVM - Ubuntu 14.04 LTS host + Ubuntu 14.04 LTS, 14.10 hosts |
description: | updated |
Changed in qemu (Ubuntu): | |
importance: | Undecided → High |
summary: |
- Ubuntu 14.04 LTS, 14.10, 15.04, 15.10 guests do not boot to Unity from - QEMU-KVM Ubuntu 14.04 LTS, 14.10, 15.04 hosts + llvmpipe i386 crashes when running on qemu64 cpu |
description: | updated |
apport information