user gets logged out from gnome-shell session after closing lid

[Fergus Incoronato]

1) What you expected to happen:

When I open the lid I expect the system to resume without logging me out.

2) What happened instead:

When I close the lid of my laptop the system suspends (as intended), and when I open the lid the system resumes (as intended).

However, if I don't suspend manually before closing the lid, on system resume it seems like I get logged out of my X session.

· I have been running different versions of Ubuntu on 2 different systems myself:

__ Machine _______| Version | DE ___| GPUs _______| Display | prop. driver
1) ThinkPad E530 _- 16.04 __- Unity - Intel _________- Xorg - no
2) ThinkPad E530 _- 16.04 __- Gnome - Intel _________- Xorg - no
3) ThinkPad T470p - 17.10 __- Gnome - Intel + Nvidia - Xorg - no
4) ThinkPad T470p - 18.04 __- Gnome - Intel + Nvidia - Xorg - yes

and this is the first time (configuration #4) that the problem presents itself.

ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: pulseaudio 1:11.1-1ubuntu7.1
ProcVersionSignature: Ubuntu 4.15.0-30.32-generic 4.15.18
Uname: Linux 4.15.0-30-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
AssertionMessage: pulseaudio: mixer.c:929: snd_mixer_elem_get_callback_private: Assertion `mixer' failed.
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/pcmC0D0p: ncrfgs 3603 F...m pulseaudio
 /dev/snd/controlC0: ncrfgs 3603 F.... pulseaudio
CurrentDesktop: ubuntu:GNOME
Date: Sat Aug 11 17:10:20 2018
ExecutablePath: /usr/bin/pulseaudio
ExecutableTimestamp: 1526913701
ProcCmdline: /usr/bin/pulseaudio --start --log-target=syslog
ProcCwd: /
Signal: 6
SourcePackage: pulseaudio
StacktraceTop:
 __assert_fail_base (fmt=0x7fc7b1c847d8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x7fc7a3bb7148 "mixer", file=file@entry=0x7fc7a3bb73d9 "mixer.c", line=line@entry=929, function=function@entry=0x7fc7a3bb7660 "snd_mixer_elem_get_callback_private") at assert.c:92
 __GI___assert_fail (assertion=0x7fc7a3bb7148 "mixer", file=0x7fc7a3bb73d9 "mixer.c", line=929, function=0x7fc7a3bb7660 "snd_mixer_elem_get_callback_private") at assert.c:101
 snd_mixer_elem_get_callback_private () from /usr/lib/x86_64-linux-gnu/libasound.so.2
 ?? () from /usr/lib/pulse-11.1/modules/module-alsa-card.so
 ?? () from /usr/lib/pulse-11.1/modules/module-alsa-card.so
Title: pulseaudio assert failure: pulseaudio: mixer.c:929: snd_mixer_elem_get_callback_private: Assertion `mixer' failed.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
dmi.bios.date: 09/28/2017
dmi.bios.vendor: LENOVO
dmi.bios.version: R0FET37W (1.17 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20J6CTO1WW
dmi.board.vendor: LENOVO
dmi.board.version: SDK0J40709 WIN
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: None
dmi.modalias: dmi:bvnLENOVO:bvrR0FET37W(1.17):bd09/28/2017:svnLENOVO:pn20J6CTO1WW:pvrThinkPadT470p:rvnLENOVO:rn20J6CTO1WW:rvrSDK0J40709WIN:cvnLENOVO:ct10:cvrNone:
dmi.product.family: ThinkPad T470p
dmi.product.name: 20J6CTO1WW
dmi.product.version: ThinkPad T470p
dmi.sys.vendor: LENOVO

[Apport retracing service (apport)]

Thank you for taking the time to report this crash and helping to make this software better. This particular crash has already been reported and is a duplicate of bug #1663528, so is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.