On 26.11.2021 22:22, Andrew Cooper wrote:
> @@ -279,6 +280,27 @@ static void init_or_livepatch _apply_alternatives(struct
> alt_instr *start,
>
> if ( dest )
> {
> + /*
> + * When building for CET-IBT, all function pointer
> targets
> + * should have an endbr64 instruction.
> + *
> + * If this is not the case, leave a warning because
> + * something is wrong with the build.
> + *
> + * Otherwise, skip the endbr64 instruction. This is a
> + * marginal perf improvement which saves on instruction
> + * decode bandwidth.
> + */
> + if ( IS_ENABLED(CONFIG_HAS_CC_CET_IBT) )
> + {
> + if ( is_endbr64(dest) )
I would have given my R-b, but I don't see where is_endbr64() is coming
from, and you don't list any prereqs here or in the cover letter. I'm
afraid I don't fancy going hunt for it in the many other pending patches.
Hence only on the assumption that the helper has got introduced before:
Reviewed-by: Jan Beulich <[email protected]>
Jan
