X server crashes with SIGBUS when resuming from suspend

[Paulo Marcel Coelho Aragão]

Every night I suspend my laptop and resume it in the morning. At least once a week, the X server crashes with SIGBUS when resuming from suspend.

I scoured systemd journals and all logs under /var/log, and this was the only suspicious message I found:

[ 59358.134] (EE) /dev/dri/card0: failed to set DRM interface version 1.4: Permission denied

As my graphics card uses driver i915, I installed xserver-xorg-video-intel-dbg but couldn't find any package with debugging symbols for xserver-xorg-core, so running 'sudo gdb --core=/core' only yielded this:

Core was generated by `/usr/lib/xorg/Xorg -core :0 -seat seat0 -auth /var/run/lightdm/root/:0 -noliste'.
Program terminated with signal SIGBUS, Bus error.
#0 0x00005631c45681f1 in ?? ()
[Current thread is 1 (LWP 1016)]
(gdb) bt
#0 0x00005631c45681f1 in ?? ()
#1 0x0000000000000001 in ?? ()
#2 0x00005631c5a03350 in ?? ()
#3 0x0000000000000001 in ?? ()
#4 0x00005631c4596ec5 in ?? ()
#5 0x00007f5f0974e2a0 in ?? ()
#6 0x00007f5f093e5977 in ?? ()
#7 0x0000000000000000 in ?? ()

I'm attaching apport's crash report.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xserver-xorg 1:7.7+19ubuntu7
ProcVersionSignature: Ubuntu 4.15.0-22.24-generic 4.15.17
Uname: Linux 4.15.0-22-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.1
Architecture: amd64
BootLog: Error: [Errno 13] Permission denied: '/var/log/boot.log'
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: XFCE
Date: Thu Jun 7 08:56:01 2018
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0116] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Dell 2nd Generation Core Processor Family Integrated Graphics Controller [1028:04b0]
InstallationDate: Installed on 2018-04-28 (39 days ago)
InstallationMedia: Xubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
MachineType: Dell Inc. Inspiron N5110
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.15.0-22-generic root=UUID=c4c2d11a-634c-4105-9991-e2fb5c18e1dc ro net.ifnames=0 quiet splash systemd.legacy_systemd_cgroup_controller=1
SourcePackage: xorg
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 05/26/2011
dmi.bios.vendor: Dell Inc.
dmi.bios.version: A06
dmi.board.name: 08FDW5
dmi.board.vendor: Dell Inc.
dmi.board.version: A06
dmi.chassis.type: 8
dmi.chassis.vendor: Dell Inc.
dmi.chassis.version: Not Specified
dmi.modalias: dmi:bvnDellInc.:bvrA06:bd05/26/2011:svnDellInc.:pnInspironN5110:pvrNotSpecified:rvnDellInc.:rn08FDW5:rvrA06:cvnDellInc.:ct8:cvrNotSpecified:
dmi.product.name: Inspiron N5110
dmi.product.version: Not Specified
dmi.sys.vendor: Dell Inc.
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.91-2
version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.0~rc5-1ubuntu1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.0~rc5-1ubuntu1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2

[Daniel van Vugt (vanvugt)]

Thanks for the bug report. The crash file shows:

Stacktrace:
 #0 0x00005631c45681f1 in ()
 #1 0x00005631c45694f1 in LogVMessageVerbSigSafe ()
 #2 0x00005631c45681a9 in ErrorFSigSafe ()
 #3 0x00005631c455b892 in xorg_backtrace ()
 #4 0x00005631c455f649 in ()
 #5 0x00007f5f09769890 in <signal handler called> () at /lib/x86_64-linux-gnu/libpthread.so.0
 #6 0x00007f5f068397d0 in () at /usr/lib/xorg/modules/drivers/modesetting_drv.so
 #7 0x00005631c446e572 in xf86CrtcSetModeTransform ()
 #8 0x00005631c4475c62 in ()
 #9 0x00005631c44b9a32 in RRCrtcSet ()
 #10 0x00005631c44bb2b3 in ProcRRSetCrtcConfig ()
 ...

but that may be inaccurate without proper retracing.

Please follow the instructions 1,6,7 from here:
https://wiki.ubuntu.com/Bugs/Responses#Missing_a_crash_report_or_having_a_.crash_attachment

[Daniel van Vugt (vanvugt)]

This looks like bug 1775751 more than any other I can find. But still please follow the above instructions.

[Paulo Marcel Coelho Aragão (marcelpaulo)]

Thanks for the swift feedback. I had tried to run:

ubuntu-bug /var/crash/FILE.crash

but it complained of lack of permission. I wasn't aware of the workaround of bug #994921. As soon as I get another crash, I'll follow your instructions.

[Paulo Marcel Coelho Aragão (marcelpaulo)]

Dummy me, forgive me: I still had the crash file around, it was just a question of giving read permission to everyone (since it was only readable by root and group whoopsie), and running ubuntu-bug over it.

So, after changing problem_types in /etc/apport/crashdb.conf to:

    'problem_types': ['Bug', 'Package', 'Crash'],

and running:

    ubuntu-bug /var/crash/_usr_lib_xorg_Xorg.0.crash

The new bug is bug #1775790.

[Daniel van Vugt (vanvugt)]

Thanks. Make it bug 1753012 then.

But it seems you are probably also suffering from bug 1775751.

[Paulo Marcel Coelho Aragão (marcelpaulo)]

I've just got an automated email saying that my bug #1775790 is a duplicate of bug #1753012, but if I try to open it, I get a not found page, I suppose because these reports are private to the subscribers.

[Paulo Marcel Coelho Aragão (marcelpaulo)]

As I started to suspect of the kernel i915 modesetting driver, yesterday I put a workaround in place, not sure if it will have any effect. I created /etc/X11/xorg.conf.d/10-intel.conf:

Section "Device"
    Identifier "Intel Graphics"
    Driver "intel"
    Option "AccelMethod" "uxa"
EndSection

[Daniel van Vugt (vanvugt)]

Bug 1753012 is now public.

[Alan Jenkins (aj504)]

Actually for frequent suspend -> SIGBUS in Xorg on Ubuntu 18.04, you also need to look at this bug:

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1776887

[Paulo Marcel Coelho Aragão (marcelpaulo)]

@Alan, oh, you're description of the bug is far more accurate than mine: it's precisely what I experienced.

I'm running vanilla kernel 4.15.0-23-generic, without your fix, so I wonder why forcing the intel driver with uxa has worked around the bug for me.