So bought RX 9070 XT and noticed that it is recommended to have split_lock_detect=off in the kernel config. Is that in Manjaro kernels?
I don’t know - you could check the config - the link is for linux616
Another option is
zcat /proc/config | less
Where did you see this? The syntax is not valid for a kernel config.
It’s a kernel parameter, not part of the kernel config.
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Oh. So it can just be added to GRUB config? I just checked with lscpu | grep split_lock_detect and it seems that my cpu doesn’t even support it.
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
The kernel’s command-line parameters — The Linux Kernel documentation
split_lock_detect= [X86] Enable split lock detection or bus lock detection When enabled (and if hardware support is present), atomic instructions that access data across cache line boundaries will result in an alignment check exception for split lock detection or a debug exception for bus lock detection. off - not enabled
x86-specific Documentation - Bus lock detection and handling — The Linux Kernel documentation