Cherry-pick request (LaunchPad bug #1871688)

[Matt Coleman]

Hi Kelsey,

Thanks for getting this into the queue!

> For now, Xenial was left out as two of the patches do not apply cleanly.


16.04 is the one that's most important for us, currently, although I am working on switching the affected systems to 20.04. We only actually have 18.04 on a handful of systems.

I applied the patches to these kernel sources:
* https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/linux-hwe/4.15.0-74.83~16.04.1/linux-hwe_4.15.0.orig.tar.gz
* https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/linux-hwe/4.15.0-74.83~16.04.1/linux-hwe_4.15.0-74.83~16.04.1.diff.gz
* https://launchpad.net/ubuntu/+archive/primary/+sourcefiles/linux-hwe/4.15.0-74.83~16.04.1/linux-hwe_4.15.0-74.83~16.04.1.dsc

The patches should apply just fine, although with an offset.

I've had this running stably for weeks on my internal 16.04 system that reproduces the issue very quickly on an unpatched kernel, so I'm eager to get this out to the rest of our fleet.

Which kernel source tree are you applying the patch to? I'll try to reproduce your exact steps and see if I have any issues with it.

Thanks again!
Matt