Re: [PATCH 1/3] Revert "x86/retpoline: Remove .text..__x86.return_thunk section"

From: Ingo Molnar
Date: Wed Oct 11 2023 - 18:42:51 EST



* Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> I don't care too deeply, I can't make up my mind either way. But perhaps
> keeping the section is easier on all the backports, it's easy to forget a
> tiny objtool patch like this.

If the objtool fix has a Fixes tag that points to one of the major
mitigation commits, then it won't be forgotten.

Arguably the new objtool is more robust against what could happen, so that
patch is not going away - and with that patch mainline doesn't have to keep
the (now ...) pointless section.

Maybe change the commit order around: first add the objtool fix, then
remove the section, pointing back to the objtool SHA1 in the very next
commit, explaining that the objtool fix enables this change. That makes it
all backporting-proof as well.

Thanks,

Ingo