• Linus Torvalds's avatar
    Merge tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip · 0a23fb26
    Linus Torvalds authored
    Pull x86 microcode loading updates from Borislac Petkov:
     "Major microcode loader restructuring, cleanup and improvements by
      Thomas Gleixner:
    
       - Restructure the code needed for it and add a temporary initrd
         mapping on 32-bit so that the loader can access the microcode
         blobs. This in itself is a preparation for the next major
         improvement:
    
       - Do not load microcode on 32-bit before paging has been enabled.
    
         Handling this has caused an endless stream of headaches, issues,
         ugly code and unnecessary hacks in the past. And there really
         wasn't any sensible reason to do that in the first place. So switch
         the 32-bit loading to happen after paging has been enabled and turn
         the loader code "real purrty" again
    
       - Drop mixed microcode steppings loading on Intel - there, a single
         patch loaded on the whole system is sufficient
    
       - Rework late loading to track which CPUs have updated microcode
         successfully and which haven't, act accordingly
    
       - Move late microcode loading on Intel in NMI context in order to
         guarantee concurrent loading on all threads
    
       - Make the late loading CPU-hotplug-safe and have the offlined
         threads be woken up for the purpose of the update
    
       - Add support for a minimum revision which determines whether late
         microcode loading is safe on a machine and the microcode does not
         change software visible features which the machine cannot use
         anyway since feature detection has happened already. Roughly, the
         minimum revision is the smallest revision number which must be
         loaded currently on the system so that late updates can be allowed
    
       - Other nice leanups, fixess, etc all over the place"
    
    * tag 'x86_microcode_for_v6.7_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
      x86/microcode/intel: Add a minimum required revision for late loading
      x86/microcode: Prepare for minimal revision check
      x86/microcode: Handle "offline" CPUs correctly
      x86/apic: Provide apic_force_nmi_on_cpu()
      x86/microcode: Protect against instrumentation
      x86/microcode: Rendezvous and load in NMI
      x86/microcode: Replace the all-in-one rendevous handler
      x86/microcode: Provide new control functions
      x86/microcode: Add per CPU control field
      x86/microcode: Add per CPU result state
      x86/microcode: Sanitize __wait_for_cpus()
      x86/microcode: Clarify the late load logic
      x86/microcode: Handle "nosmt" correctly
      x86/microcode: Clean up mc_cpu_down_prep()
      x86/microcode: Get rid of the schedule work indirection
      x86/microcode: Mop up early loading leftovers
      x86/microcode/amd: Use cached microcode for AP load
      x86/microcode/amd: Cache builtin/initrd microcode early
      x86/microcode/amd: Cache builtin microcode too
      x86/microcode/amd: Use correct per CPU ucode_cpu_info
      ...
    0a23fb26
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