Christophe Leroy <christophe.le...@c-s.fr> writes: > Only the get_user() in store_updates_sp() has to be done outside > the mm semaphore. All the comparison can be done within the semaphore, > so only when really needed. > > As we got a DSI exception, the address pointed by regs->nip is > obviously valid, otherwise we would have had a instruction exception. > So __get_user() can be used instead of get_user()
I don't think that part is true. You took a DSI so there *was* an instruction at NIP, but since then it may have been unmapped by another thread. So I don't think you can assume the get_user() will succeed. cheers
