Le 24/05/2022 à 12:15, Naveen N. Rao a écrit : > Christophe Leroy wrote: >> >> >> Le 23/05/2022 à 19:55, Sathvika Vasireddy a écrit : >>> Architectures can select HAVE_NOP_MCOUNT if they choose >>> to nop out mcount call sites. If that config option is >>> selected, then --mnop is passed as an option to objtool, >>> along with --mcount. >>> >> >> Is there a reason not to nop out mcount call sites on powerpc as well ? > > Yes, if there are functions that are out of range of _mcount(), then the > linker would have inserted long branch trampolines. We detect such cases > during boot. But, if we nop out the _mcount call sites during build > time, we will need some other way to identify these. >
But does it really matter whether _mcount is reachable or not ? _mcount is never used, and the function we want to call in lieu of _mcount might be reachable while _mcount is not or might be unreachable while _mcount is. Christophe
