Most likely you have the mitigation already in place, that is disabeling the XTheadVector extension. The regular distributions don't enable it, since it's a non standard incompatible vendor extension based on a draft spec.

When I wanted to benchmark their implementation last year I patched a kernel to enable it, and needed to consult the open source part of the core [0] to figure out that they placed the enable CSR bit in a different location than the final ratified spec. [1]

[0] https://github.com/T-head-Semi/openc906 (doesn't include XTheadVector extension)

[1] https://github.com/camel-cdr/rvv-d1

From the article:

> No, software updates or patches cannot fix this vulnerability because it is a hardware bug. The only mitigation is to disable the vector extension in the CPU, which unfortunately impacts the CPU’s performance.

Do you let people run arbitrary code on your linux box? If not, you don't have anything to worry about, as far as I can see.