Re: [PATCH 47/48] objtool: Improve and simplify prefix symbol detection
From: Peter Zijlstra
Date: Thu Apr 23 2026 - 11:29:27 EST
On Thu, Apr 23, 2026 at 08:19:57AM -0700, Josh Poimboeuf wrote:
> On Thu, Apr 23, 2026 at 10:55:20AM +0200, Peter Zijlstra wrote:
> > On Wed, Apr 22, 2026 at 09:04:15PM -0700, Josh Poimboeuf wrote:
> > > Only create prefix symbols for functions that have
> > > __patchable_function_entries entries, since those are the only functions
> > > where prefix NOPs are intentional.
> >
> > __CFI_TYPE() as used in SYM_TYPED_ENTRY() will also generate the NOPs
> > but will not have __patchable_function_entries, because ASM not
> > compiler.
>
> Hm, but those already have __cfi_ symbols, no?
Yes, but you said those were 'short' -- but fair, I did not check if the
asm stub generated symbols of the correct length.