Re: Bug report for kernel v4.15-rc8+

From: Thomas Gleixner
Date: Tue Aug 10 2021 - 13:09:36 EST

On Tue, Aug 10 2021 at 16:05, blinkin@xxxxxxxx wrote:
> The general symptom is a slow and unresponsive system (e.g. on gnome
> there's a delay before displaying typed characters, up to 3-5
> seconds. Animations are jittering, mouse clicks sometimes are missed).
> 3D games are now impossible to play due to poor performance.
> System feels as if the CPU is always busy (htop shows one core at ~
> 90% most of the time both with and without the workaround, not sure
> it's correlated)

That's definitely wrong. What is consuming CPU time?

> It's running OpenSuse Leap 15.2 (the bug came out when upgrading from
> 15.1, thus going from kernel 4.12 to 5.3) I suspect the same bug is
> responsible for making me switch to suse after failing to upgrade
> debian from 9 (kernel 4.9) to 10 (kernel 4.19)
> The workaround is to pass irqaffinity=0 on boot.
> Attached: dmesg output with and without the irqaffinity parameter,
> lspci output, /proc/cpuinfo contents.
> Let me know what else is needed.

1) You're booting with an out of tree module:

> [ 17.080069] vboxdrv: loading out-of-tree module taints kernel.

Please reproduce without this.

2) Please provide information what is consuming 90% of a CPU

3) Please provide the output of /proc/interrupts for both boot scenarios

Take a snapshot right after boot and another one a minute later.