On Thu, Mar 30 2023 at 19:05, Borislav Petkov wrote: > On March 30, 2023 6:46:24 PM GMT+02:00, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote: >>So that violates the rules of microcode loading that the sibling must be >>in a state where it does not execute anything which might be affected by >>the microcode update. The fragile startup code does not really qualify >>as such a state :) > > Yeah I don't think we ever enforced this for early loading. We don't have to so far. CPU bringup is fully serialized so when the first sibling comes up the other one is still in wait for SIPI lala land. When the second comes up it will see that the microcode is already up to date. Thanks, tglx