this post was submitted on 25 Jul 2023
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Encryption-breaking, password-leaking bug in many AMD CPUs could take months to fix (arstechnica.com)
submitted 1 year ago by Lanky_Pomegranate530@lemmy.world to c/technology@lemmy.world
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[โ€“] evatronic@lemm.ee 38 points 1 year ago (1 children)

It's worth noting these are the firmware / microcode fixes.

There's already a software solution available,

There is a software workaround, you can set the chicken bit DE_CFG[9]. This may have some performance cost, and the microcode update is preferred.

source: https://www.openwall.com/lists/oss-security/2023/07/24/3

AMD has also already released a fix for the big boy - the EPYC processor.

[โ€“] drdabbles@lemmy.world 1 points 1 year ago

The MSR bit is potentially a large performance loss and AMD recommends their partners not use it. In my tests is was 5-15% on EPYC depending on workload. "Some performance cost" is really hiding the reality of that bit.