[PATCH 0/9] x86,objtool: Optimize !RETPOLINE

From: Peter Zijlstra
Date: Fri Mar 12 2021 - 12:18:40 EST


Hi,

Now that Juergen's paravirt rework, which included the negative alternative
stuff, landed in tip, here's a respin of my retpoline patches.

The main feature is replacing the compiler generated (tail) calls to
__x86_indirect_thunk_\reg with an ALTERNATIVE that replaces them with regular
indirect call instructions, eliding the double jump.

Patches rely on tip/objtool/core and tip/x86/alternatives