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    x86/msr-index: Clean up bit defines for IA32_FEATURE_CONTROL MSR · 32ad73db
    Sean Christopherson authored
    
    
    As pointed out by Boris, the defines for bits in IA32_FEATURE_CONTROL
    are quite a mouthful, especially the VMX bits which must differentiate
    between enabling VMX inside and outside SMX (TXT) operation.  Rename the
    MSR and its bit defines to abbreviate FEATURE_CONTROL as FEAT_CTL to
    make them a little friendlier on the eyes.
    
    Arguably, the MSR itself should keep the full IA32_FEATURE_CONTROL name
    to match Intel's SDM, but a future patch will add a dedicated Kconfig,
    file and functions for the MSR. Using the full name for those assets is
    rather unwieldy, so bite the bullet and use IA32_FEAT_CTL so that its
    nomenclature is consistent throughout the kernel.
    
    Opportunistically, fix a few other annoyances with the defines:
    
      - Relocate the bit defines so that they immediately follow the MSR
        define, e.g. aren't mistaken as belonging to MISC_FEATURE_CONTROL.
      - Add whitespace around the block of feature control defines to make
        it clear they're all related.
      - Use BIT() instead of manually encoding the bit shift.
      - Use "VMX" instead of "VMXON" to match the SDM.
      - Append "_ENABLED" to the LMCE (Local Machine Check Exception) bit to
        be consistent with the kernel's verbiage used for all other feature
        control bits.  Note, the SDM refers to the LMCE bit as LMCE_ON,
        likely to differentiate it from IA32_MCG_EXT_CTL.LMCE_EN.  Ignore
        the (literal) one-off usage of _ON, the SDM is simply "wrong".
    
    Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
    Signed-off-by: default avatarBorislav Petkov <bp@suse.de>
    Link: https://lkml.kernel.org/r/20191221044513.21680-2-sean.j.christopherson@intel.com
    32ad73db