I'm trying to understand the effective use of this ability, as my magus is about to hit level 7. And there are a few spells on the spell lists that are un-available except to certain races.
1) Racial spell(s) --
Such as "Blend", which is typically an "elf" racial spell. It doesn't say only elves can cast it, just the following:
"This spell was originally created for Elves. Characters or creatures of other races can learn to cast it with GM permission."
But doesn't say anything about casting it being restricted to race, only acquiring the spell initially.
2) Using "Knowledge Pool (Su)" ...
As written, I see no reason why the magus could NOT temporarily "memorize" a racial spell that is on the magus list ... As it is; from the magus spell list
"At 7th level, when a magus prepares his magus spells, he can decide to expend 1 or more points from his arcane pool, up to his Intelligence bonus. For each point he expends, he can treat any one spell from the magus spell list as if it were in his spellbook and can prepare that spell as normal that day. If he does not cast spells prepared in this way before the next time he prepares spells, he loses those spells. He can also cast spells added in this way using his spell recall ability, but only until he prepares spells again."
For clarity; I'm not concerned about Pathfinder Society rules ... just standard pathfinder. And if you disagree, please cite specific rules and not just opinions.
edit refined the question to only relate to knowledge pool and racial spells ... as writing spells "memorized" with Knowledge Pool has been previously addressed.