Unexpected shutdown after fans full blast

[linux-aarhus]

@rodders

Too hasty,! It came back so it wasn’t the fans after all.

From what I recall the crash is intentional - so what are you doing when this happens?

Is the log containing same message as last time?

@rodders

Not sure where to go next but a BIOS update is the last straw I can think to clutch.

Did you try creating the following configuration?

@linux-aarhus

If affected - create a file /etc/sysctl.d/split-lock-mitigate.conf

kernel.split_lock_mitigate=0

sudo sysctl --system

@rodders

Jan 05 11:12:41 isildur kernel: x86/split lock detection: #AC: crashing the kernel on kernel split_locks and warning on user-space split_locks

Are you playing a game which utilise split lock?

Did you read the background on split lock and why the kernel will crash itself?

@linux-aarhus

Read this article to understand what this is and why … it may not be needed at all.

The search for the correct amount of split-lock misery [LWN.net]

As I understand - it should not be applied as general measure - only if strictly necessary for a specific application.

The definitive answer, though, came from Thomas Gleixner, who pointed out that slowing down split lockers by default is the only choice that distributors could make; anything else creates an easily exploitable denial-of-service vulnerability. So the slowdown needs to remain: “Attack vector prevention has precedence over broken applications”. He did suggest, though, that a sysctl knob could be added to control split-lock detection; that would allow users of broken applications to get their performance back without the need to figure out how to change command-line parameters or reboot their systems.

That is the approach that Piccoli has taken for his second attempt at addressing the problem. The new kernel.split_lock_mitigate knob, if set to zero, will disable the penalization of processes using split locking (while retaining the warning sent to the system log). The default is to retain the slowdown. This patch seems to have pleased everybody involved and looks likely to find its way into the 6.2 kernel. Affected gamers will have to set the new knob appropriately, but knowing which sysctls to tweak could be said to be part of being a true God of War.

If affected - create a file /etc/sysctl.d/split-lock-mitigate.conf

kernel.split_lock_mitigate=0

sudo sysctl --system

Search for sysctl kernel.split_lock_mitigate