Paolo Bonzini <pbonz...@redhat.com> writes:
> On 30/09/2016 23:31, Alex Bennée wrote:
>> tb = atomic_rcu_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(pc)]);
>> - if (unlikely(!tb || tb->pc != pc || tb->cs_base != cs_base ||
>> - tb->flags != flags)) {
>> + if (unlikely(!tb || atomic_read(&tb->pc) != pc ||
>> atomic_read(&tb->cs_base) != cs_base ||
>> + atomic_read(&tb->flags) != flags)) {
>
> This should not be necessary (and is responsible for the 64-on-32
> compilation failure). The load of tb from the cache is an acquire
> operation, and synchronizes with the corresponding store in
> cpu->tb_jmp_cache.
Is the C11 spec happy with "plain" accesses after the acquire operation?
Unfortunately the sanitizer isn't able to see the indirect acquires
effect on the other accesses.
>
> Paolo
--
Alex Bennée
