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126 points bundie | 1 comments | 01 Jul 25 08:32 UTC | HN request time: 0.226s | source

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csense ◴[03 Jul 25 22:42 UTC] No.44459751[source]▶

>>44431828 (OP) #

Can you write a kernel patch / driver to trap the unsupported instructions and provide software implementations?

replies(2): >>44459767 #>>44461893 #

karlgkk ◴[03 Jul 25 22:46 UTC] No.44459767[source]▶

>>44459751 #

Rva20 lacks vector support and hypervisor instructions, among other things.

You’re welcome to put a ton of effort in for dogshit performance on a bunch or $35 SBCs but the rest of us will just upgrade

And don’t worry, some vendor won’t come in and magically save you - fedora is eyeing rv22 as their baseline.

replies(4): >>44460056 #>>44460232 #>>44460237 #>>44460407 #

1. slyall ◴[04 Jul 25 00:29 UTC] No.44460232[source]▶

>>44459767 #

The Linux Kernel has math coprocessor emulation (mainly floating point stuff) that can be enabled if your CPU doesn't include it. This was common with consumer CPUs in the 1990s and some embedded CPUs today.

Link here, although I'm sure it existed well before 2.6.12

https://www.kernelconfig.io/config_math_emulation

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