Do I need to take action regarding my Microarchitectural Data Sampling (MDS) status?

Question

My dmesg output contains the following line:

[    0.265021] MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.

Having gone to the above-mentioned site and having read up on MDS a little, I ran/received the following:

$ cat /sys/devices/system/cpu/vulnerabilities/mds Mitigation: Clear CPU buffers; SMT vulnerable

According to the site, this translates to:

'Mitigation: Clear CPU buffers' ... The processor is vulnerable and the CPU buffer clearing mitigation is enabled.
'SMT vulnerable' ... SMT is enabled

I don't have a lot of experience in computing, but from what I can tell (and please correct me if I'm wrong), my system is doing what it can to protect against MDS.

My question is:

Can I do anything further to protect my system, and if so, what should my next steps be?

Answer 1

Can I do anything further to protect my system, and if so, what should my next steps be?

You can do something further to protect your system: you can disable SMT (hyperthreading). This is usually possible in your system’s firmware setup.

Do I need to take action regarding my Microarchitectural Data Sampling (MDS) status?

That depends on what you use your system for. As a general rule, if you only run trusted applications with trusted content, you don’t need to take further action. (The jury is still out regarding web browsers’ vulnerability to MDS with SMT.) If you run VMs or containers with unvetted contents, you might be at risk.