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    SubjectRe: [PATCH v2 07/39] x86/entry: Sprinkle ENDBR dust
    On Thu, Feb 24, 2022 at 03:51:45PM +0100, Peter Zijlstra wrote:
    > Kernel entry points should be having ENDBR on for IBT configs.
    >
    > The SYSCALL entry points are found through taking their respective
    > address in order to program them in the MSRs, while the exception
    > entry points are found through UNWIND_HINT_IRET_REGS.
    >
    > The rule is that any UNWIND_HINT_IRET_REGS at sym+0 should have an
    > ENDBR, see the later objtool ibt validation patch.

    Could the "rule" be changed to only check global syms? It seems
    unlikely a local symbol would need ENDBR.

    Then you wouldn't need this annotation:

    > SYM_CODE_START_LOCAL(early_idt_handler_common)
    > + UNWIND_HINT_IRET_REGS offset=16
    > + ANNOTATE_NOENDBR
    > /*
    > * The stack is the hardware frame, an error code or zero, and the
    > * vector number.

    --
    Josh

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