Today's Patch Tuesday helps harden AMD CPUs against Spectre
Today is April's Patch Tuesday for Microsoft operating systems, and AMD CPU owners will want to fire up Windows Update as soon as possible. This round of patching includes operating-system-level mitigations for Spectre Variant 2, also known as CVE-2017-5715, on at least some AMD processors running Windows 10. The update exposes control over the Indirect Branch Prediction Barrier, or IBPB, within AMD CPUs that support the feature. According to AMD's latest security white paper, using the IBPB is the company's recommended mitigation for Spectre Variant 2.
While its CPUs do support other methods of controlling the behavior of the branch predictor in response to past predictions (a special bit indicating Indirect Branch Restricted Spectulation, or IBRS) and ...