> > +++ b/kernel/livepatch/core.c > > @@ -143,11 +143,13 @@ static int klp_find_callback(void *data, const char *name, > > args->count++; > > > > /* > > - * Finish the search when the symbol is found for the desired position > > - * or the position is not defined for a non-unique symbol. > > + * Finish the search when unique symbol names are enabled > > + * or the symbol is found for the desired position or the > > + * position is not defined for a non-unique symbol. > > */ > > - if ((args->pos && (args->count == args->pos)) || > > - (!args->pos && (args->count > 1))) > > + if (IS_ENABLED(CONFIG_LD_HAS_Z_UNIQUE_SYMBOL) || > > + (args->pos && args->count == args->pos) || > > + (!args->pos && args->count > 1)) > > return 1; > > There's no real need to do this. The code already works as-is, even if > there are no unique symbols. > > Even if there are no duplicates, there's little harm in going through > all the symbols anyway, to check for errors just in case something > unexpected happened with the linking (unexpected duplicate) or the patch > creation (unexpected sympos). It's not a hot path, so performance isn't > really a concern. Correct. > When the old linker versions eventually age out, we can then go strip > out all the sympos stuff. Yes. > > @@ -169,6 +171,13 @@ static int klp_find_object_symbol(const char *objname, const char *name, > > else > > kallsyms_on_each_symbol(klp_find_callback, &args); > > > > + /* > > + * If the LD's `-z unique-symbol` flag is available and enabled, > > + * sympos checks are not relevant. > > + */ > > + if (IS_ENABLED(CONFIG_LD_HAS_Z_UNIQUE_SYMBOL)) > > + sympos = 0; > > + > > Similarly, I don't see a need for this. If the patch is legit then > sympos should already be zero. If not, an error gets reported and the > patch fails to load. My concern was that if the patch is not legit (that is, sympos is > 0 for some reason), the error would be really cryptic and would not help the user at all. So zeroing sympos seems to be a good idea to me. There is no harm and the change is very small and compact. On the other hand, I do not insist on this. Regards, Miroslav
