Comment 9 for bug 966868

Forwarding this bug from Ubuntu reporter Florin:
http://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/966868

[Problem]
On Ubuntu there appears to be a race condition in libdrm during boot. It appears the i915 drm device exists but isn't fully initialized at the time plymouth wants to use it.

Note I'm filing this against -intel just because it's the intel portion of libdrm where the code is passing through; I think this is really a libdrm bug.

[Original Description]
After a force restart of Ubuntu, I've got a System Crash error after logging in.

lsb_release -rd
Description: Ubuntu precise (development branch)
Release: 12.04

This looks more like a libdrm bug. There's a race condition with the i915 device not being ready by the time plymouth is starting. Possibly it's because it doesn't have drm master.

<Sarvatt> apparently chromeos works around it with http://git.chromium.org/gitweb/?p=chromiumos/third_party/kernel.git;a=commit;h=32a8c5b67163a6ae211ff2683c999b6ad2c76d1f but thats just working around the problem..

googling intel/intel_bufmgr_gem.c:2783 turns up a lot of hits.

The code in question with the assert is:

 if (IS_GEN2(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 2;
        else if (IS_GEN3(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 3;
 else if (IS_GEN4(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 4;
        else if (IS_GEN5(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 5;
        else if (IS_GEN6(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 6;
        else if (IS_GEN7(bufmgr_gem->pci_device))
                bufmgr_gem->gen = 7;
        else
                assert(0);

$ xpci 8086:0126
snb-m-gt2+ (8086:0126) sandybridge

So it should be going into the IS_GEN6 branch.

Thanks!

ProblemType: Crash
DistroRelease: Ubuntu 12.04
Package: plymouth 0.8.2-2ubuntu28
ProcVersionSignature: Ubuntu 3.2.0-20.33-generic 3.2.12
Uname: Linux 3.2.0-20-generic x86_64
ApportVersion: 1.95-0ubuntu1
Architecture: amd64
Date: Wed Mar 28 09:33:16 2012
DefaultPlymouth: /lib/plymouth/themes/ubuntu-logo/ubuntu-logo.plymouth
ExecutablePath: /sbin/plymouthd
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Alpha amd64 (20120322)
MachineType: LENOVO 4284BZ4
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-20-generic root=UUID=f1bb4518-a890-49c0-9339-ecc3d8bd2658 ro quiet splash vt.handoff=7
ProcCmdline: /sbin/plymouthd --mode=boot --attach-to-session
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
ProcFB: 0 inteldrmfb
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-20-generic root=UUID=f1bb4518-a890-49c0-9339-ecc3d8bd2658 ro quiet splash vt.handoff=7
Signal: 6
SourcePackage: plymouth
TextPlymouth: /lib/plymouth/themes/ubuntu-text/ubuntu-text.plymouth
Title: plymouthd crashed with SIGABRT in raise()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

dmi.bios.date: 01/19/2012
dmi.bios.vendor: LENOVO
dmi.bios.version: 8BET56WW (1.36 )
dmi.board.asset.tag: Not Available
dmi.board.name: 4284BZ4
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr8BET56WW(1.36):bd01/19/2012:svnLENOVO:pn4284BZ4:pvrThinkPadW520:rvnLENOVO:rn4284BZ4:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 4284BZ4
dmi.product.version: ThinkPad W520
dmi.sys.vendor: LENOVO