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    Subject[PATCH 5.10 079/148] x86/cpufeatures: Move RETPOLINE flags to word 11
    Date
    From: Peter Zijlstra <peterz@infradead.org>

    commit a883d624aed463c84c22596006e5a96f5b44db31 upstream.

    In order to extend the RETPOLINE features to 4, move them to word 11
    where there is still room. This mostly keeps DISABLE_RETPOLINE
    simple.

    Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    Signed-off-by: Borislav Petkov <bp@suse.de>
    Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
    Signed-off-by: Borislav Petkov <bp@suse.de>
    Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
    [bwh: Backported to 5.10: bits 8 and 9 of word 11 are also free here,
    so comment them accordingly]
    Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
    ---
    arch/x86/include/asm/cpufeatures.h | 10 ++++++++--
    1 file changed, 8 insertions(+), 2 deletions(-)

    --- a/arch/x86/include/asm/cpufeatures.h
    +++ b/arch/x86/include/asm/cpufeatures.h
    @@ -203,8 +203,8 @@
    #define X86_FEATURE_PROC_FEEDBACK ( 7*32+ 9) /* AMD ProcFeedbackInterface */
    #define X86_FEATURE_SME ( 7*32+10) /* AMD Secure Memory Encryption */
    #define X86_FEATURE_PTI ( 7*32+11) /* Kernel Page Table Isolation enabled */
    -#define X86_FEATURE_RETPOLINE ( 7*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
    -#define X86_FEATURE_RETPOLINE_LFENCE ( 7*32+13) /* "" Use LFENCE for Spectre variant 2 */
    +/* FREE! ( 7*32+12) */
    +/* FREE! ( 7*32+13) */
    #define X86_FEATURE_INTEL_PPIN ( 7*32+14) /* Intel Processor Inventory Number */
    #define X86_FEATURE_CDP_L2 ( 7*32+15) /* Code and Data Prioritization L2 */
    #define X86_FEATURE_MSR_SPEC_CTRL ( 7*32+16) /* "" MSR SPEC_CTRL is implemented */
    @@ -290,6 +290,12 @@
    #define X86_FEATURE_FENCE_SWAPGS_KERNEL (11*32+ 5) /* "" LFENCE in kernel entry SWAPGS path */
    #define X86_FEATURE_SPLIT_LOCK_DETECT (11*32+ 6) /* #AC for split lock */
    #define X86_FEATURE_PER_THREAD_MBA (11*32+ 7) /* "" Per-thread Memory Bandwidth Allocation */
    +/* FREE! (11*32+ 8) */
    +/* FREE! (11*32+ 9) */
    +/* FREE! (11*32+10) */
    +/* FREE! (11*32+11) */
    +#define X86_FEATURE_RETPOLINE (11*32+12) /* "" Generic Retpoline mitigation for Spectre variant 2 */
    +#define X86_FEATURE_RETPOLINE_LFENCE (11*32+13) /* "" Use LFENCE for Spectre variant 2 */

    /* Intel-defined CPU features, CPUID level 0x00000007:1 (EAX), word 12 */
    #define X86_FEATURE_AVX512_BF16 (12*32+ 5) /* AVX512 BFLOAT16 instructions */

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