Issue with Kernel Panic on Dell Latitude 7490 and i915

English Hardware
#1

I have a few Dell Latitude 7490 i7 laptops.
On most Leap 15.4 install, updates, reboots and works.

On some Leap 15.4 installs, updates, reboots, get the gui and panics with the caps lock blinking (kernel panic).

After a lot of searching the internet and lots of bad and incorrect info, I added 2 of the “fixes” to the bootup kernel parameters and no kernel panic - up for 12 hours now.

I had to add i915.modeset=0 nomodeset to the startup line to get it stable.

I am not sure why that fixed the problem. Have I disabled the i915 driver doing that?

Why does windows 10 and 11 have no problems on the same laptops that Leap panics on?

#2

When that is your question, you should concentrate on the question why many manufacturers work together with Microsoft to let their hardware function, but never cooperate with Linux.

#3

It is the same i7-8650U cpu with integrated graphics. Since that is supposed to be i915 driver and intel does support Linux (ok, not to the extent of Windows). Intel’s support is better than AMD’s and a lot better than Nvidia’s.

I wonder if the shared memory for the video is the problem. Maybe the i915 driver see more memory than allocated by the booting causing the panic.

#4

It seems that you did not understand my inquiry.

Do you want to discuss the support of Windows for your system (as your question implies), or do you want help with your problem on openSUSE (which you did not ask for at all)?

#5

I have opened a bugzilla on it and am attempting to link another computer to it to get the kernel crash.

It is weird that the leap 15.4 iso boots with no issue but the tumbleweed current iso also has to have the i915.modeset=0 to boot to install.

So far nothing in lspci is different between those that work and those that panic. I swapped memory - no difference, I swapped the nvme - It stayed with the laptop that panics.

I posted this mainly to help anyone else that has an intel laptop and gets kernel panics.

#6

After lots of searching and looking at i915 code. Someone on the Arch boards discovered that many early low power intel cpu’s have a power management bug that causes the kernel to core in the i915 driver.

The cure it to add i915.enable_dc=0 and make sure that you do not have the nomodeset on the GRUB_CMDLINE_LINUX_DEFAULT line on /etc/default/grub.

This fixed the 3 laptops that had the problem with kernel panics.

It does cause the battery life to be about 10% shorter due to gpu being at a higher power than needed.