Re: [PATCH] kbuild: Remove CONFIG_DEBUG_SECTION_MISMATCH

From: Peter Zijlstra
Date: Fri Apr 08 2022 - 15:14:56 EST


On Sat, Apr 09, 2022 at 03:29:21AM +0900, Masahiro Yamada wrote:
> Is [2] caused by dead code that was not optimized out
> due to the unusual inlining decisions by the compiler ?

The complaint is due to SMAP validation; objtool will scream if there's
a CALL in between STAC/CLAC. The thinking is that since they open a
security window, we want tight code between them. We also very much
don't want tracing and other funnies to happen there. As such, any CALL
is dis-allowed.

This weird option is having us upgrade quite a few 'inline' to
'__always_inline'.