How to check if Zenbleed mitigation(chicken bit) is properly set? - eviltoast
  • trachemys@iusearchlinux.fyi
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    1 year ago
    echo $(($(rdmsr -c 0xc0011029) & (1<<9) )) 
    

    Should return 512. You might need a ‘sudo’ before the rdmsr (any permission errors in any of this means it didn’t work). Unfortunately, this needs to be done every time you reboot. The next security update for linux will do this automatically.

    • notme@lemmy.worldOP
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      1 year ago

      Thanks, it works. That’s a bit worrying.

      Do you think Ubuntu 22.04 will get the security update soon? I got a microcode update today but i think that’s only a fix for server cpus and not desktop cpus.

      For anyone having permission problems turn off secure boot in order for this to work.

        • notme@lemmy.worldOP
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          1 year ago

          I thought that was only for Eypc processors with desktop processor fixes coming later this year. The articles are not very clear with what is fixed when.

          • YonatanAvhar@programming.dev
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            1 year ago

            I also read that fixes are being released now for the high-end chips, but the desktop fixes will be released significantly later