Unable to switch back to nvidia after suspend on intel

[Jean-Francois Labonte]

I am not sure that it is something that an issue caused by nvidia-prime
or if it is something that is cause in the drivers or if it is a bug with
the kernel itself, cause it seems to be a problem with Linux PM, so this bug
could be moved if needed

*** What's Wrong? ***

As the title states, I am unable to use the Nvidia GPU when I have changed profile for intel then computer on suspend for more than 30 minutes ( This has to be determined precisely how long until I get the issue ) and then set back the profile to nvidia.

So basically, it seems that the nvidia modules are unable to be loaded, I have tried to fix
the issue using bbswitch. It doesn't work neither, if the /sys/bus/pci/devices/0000\:01\:00.0/power/control is set to auto, I am unable to load the kernel modules anymore.

*** What do I expect ***

Well, I was hoping that I would be able to keep my laptop on and simply switch from one GPU to other
seamlessly. It is, until I put my laptop on suspend for an extended time while I am on powersaving mode

************************

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: nvidia-prime 0.8.10
Uname: 5.0.0-14-generic #15-Ubuntu x86_64
NonfreeKernelModules: nvidia_uvm nvidia_modeset nvidia
Architecture: amd64
CurrentDesktop: MATE
CurrentDM: GDM3
Date Thursday May 2nd 2019 7:49 PM
InstallationDate: Installed on (0 days ago)
SourcePackage: nvidia-prime
UpgradeStatus: No upgrade log present (fresh install)

Description: Ubuntu 19.04
Release: 19.04
nvidia-prime:
  Installed: 0.8.10
  Candidate: 0.8.10
  Version table:
 *** 0.8.10 500
        500 http://ca.archive.ubuntu.com/ubuntu disco/main amd64 Packages
        500 http://ca.archive.ubuntu.com/ubuntu disco/main i386 Packages
        100 /var/lib/dpkg/status

/var/lib/dpkg/status -> https://paste.ubuntu.com/p/McmJHRgjTH/

https://paste.ubuntu.com/p/Pxnw7mDmzQ/ -> dmesg before issue

**** MORE dmesg will come, need to get fresh data! *****

[Jean-Francois Labonte (grimsleepless12)]

The issue happens also when I am using lightdm

This is the result of my nvidia-smi

https://paste.ubuntu.com/p/sj2bF3vxPd/

The dmesg when I have the issue:

https://paste.ubuntu.com/p/sj2bF3vxPd/

[Jean-Francois Labonte (grimsleepless12)]

Laptop Model XPS 15 9560

lspci -> https://paste.ubuntu.com/p/6FYhKSXQZN/

[Jean-Francois Labonte (grimsleepless12)]

I am planning to test this command :

`echo "1" > /sys/bus/pci/devices/0000\:01\:00.0/reset`

[Jean-Francois Labonte (grimsleepless12)]

I have been able to reset my PCI with the following command:

```
echo "1" > /sys/bus/pci/devices/0000\:01\:00.0/remove
sleep 1
echo "1" > /sys/bus/pci/rescan
```