On Mon, Jan 23, 2023, Kim Phillips wrote: > The AMD Zen4 core supports a new feature called Automatic IBRS > (Indirect Branch Restricted Speculation). > > Enable Automatic IBRS by default if the CPU feature is present. > It typically provides greater performance over the incumbent > generic retpolines mitigation. > > Patch 1 [unchanged from v7] Adds support for the leaf that > contains the AutoIBRS feature bit. > > Patch 2 moves the leaf's open-coded code from __do_cpuid_func() > to kvm_set_cpu_caps() in preparation for adding the features in > their native leaf. > > Patches 3-6 introduce the new leaf's supported bits one by one. > > Patch 7 [unchanged from v7] Adds support for AutoIBRS by turning > its EFER enablement bit on at startup if the feature is available. > > Patch 8 [unchanged from v7] Adds support for propagating AutoIBRS > to the guest. A few nits, but otherwise looks good. Thanks!
