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Ubuntu 25.10 Raises RISC-V Profile Requirements

(www.omgubuntu.co.uk)
126 points bundie | 1 comments | 01 Jul 25 08:32 UTC | HN request time: 0.207s | source
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londons_explore ◴[05 Jul 25 07:17 UTC] No.44470723[source]▶
Why can't these older processors be supported via a software shim for unrecognised instructions?

It is far better for software to run with a couple of percent slowdown on old cpus only than not run at all.

replies(2): >>44471147 #>>44471356 #
1. snvzz ◴[05 Jul 25 08:43 UTC] No.44471147[source]▶
>Why can't these older processors be supported via a software shim for unrecognised instructions?

It can.

It's just this shim is out of scope for Ubuntu.

Refer to opensbi instruction emulation.

>It is far better for software to run with a couple of percent slowdown on old cpus only than not run at all.

With features like vector instructions or pointer masking, we're talking a non-trivial slowdown.