>> No #MC on stores. Just on loads. Note that you can't clear poison >> state with a series of small writes to the cache line. But a single >> 64-byte store might do it (architects didn't want to guarantee that >> it would work when I asked about avx512 stores to clear poison >> many years ago). > > Dave Jiang thinks MOVDIR64B clears poison. > > http://archive.lwn.net:8080/linux-kernel/157617505636.42350.1170110675242558018.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxx/ MOVDIR64B has some explicit guarantees (does a write-back invalidate if the target is already in the cache) that a 64-byte avx512 write doesn't. Of course it would stop working if some future CPU were to have a longer than 64 bytes cache line. -Tony
