Post #723195

2026-03-17 14:36 UTC

New article! A user *cough* @aras *cough* is reporting full system freezes while using Superluminal on Linux. What do you do? Cry? Well, we did a little bit. But we also dove into the kernel...again, this time finding &amp; fixing several issues in eBPF&#39;s spinlock implementation. Read all about it: https://rovarma.com/articles/a-tale-about-fixing-ebpf-spinlock-issues-in-the-linux-kernel/

Replies (9)

@agersant@mastodon.gamedev.place 2026-03-17 15:32

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place excellent read, thank you for explaining all this in an approachable and easy to read format! 👏👏

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@morten_skaaning@mastodon.gamedev.place 2026-03-17 16:18

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place what a journey 😊 best wishes for pushing Superluminal to be excellent for Linux🥇

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@ca1ne@mastodon.gamedev.place 2026-03-17 17:40

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place Great article!....and now my anticipation for Superluminal on Linux is even higher. Take my money! :D

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@aras@mastodon.gamedev.place 2026-03-17 17:45

@rovarma@mastodon.gamedev.place great post! (kinda proud of myself that my very eyeball-y guess “200ms stalls” turned out to be almost exactly correct :)) Would be good to clarify why only certain kernel versions were affected, since now not clear why only I could see the problem initially

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@davidgmbb@mastodon.social 2026-03-17 18:17

@rovarma@mastodon.gamedev.place Great post. I can't wait to use Superluminal on Linux :)

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@aachrisg@mastodon.gamedev.place 2026-03-18 06:38

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place Will a cheap rs232 to ethernet adapter + rs232 card work for kernel debuggjng? The advantage would be that you only need this on the target machine to gain access to it from any computer that can see its ip addr.

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@mk@bsd.network 2026-03-18 20:28

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place great story and writeup! Also, it's good to hear Superluminal is coming to Linux. It might be useful should I one day decide to add bugs to my code. (:

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@Logical_Error@fosstodon.org 2026-03-19 06:38

@rovarma@mastodon.gamedev.place @aras@mastodon.gamedev.place what a great and approachable read! looking to see how i can use this same digestible prose for my blog

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@michaelc@mastodon.gamedev.place 2026-03-22 05:24

@rovarma@mastodon.gamedev.place Engaging read! One lingering question: after the fixes, ringbuf_reserve in the NMI sampling event fails because the lock detects and rejects reentrancy, right? (Just quickly, instead of after 250ms.) That seems… scary? I guess you just don’t get a sample, and that’s not the end of the world for a profiler? Are there other NMI you instrument where a failure like this might drop important information?

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