Re: [PATCH v8 3/3] x86, mce: Add __mcsafe_copy()

[Dan Williams]

On Sat, Jan 9, 2016 at 11:39 AM, Tony Luck <tony.luck@xxxxxxxxx> wrote:
> On Sat, Jan 9, 2016 at 9:57 AM, Andy Lutomirski <luto@xxxxxxxxxxxxxx> wrote:
>> On Sat, Jan 9, 2016 at 9:48 AM, Tony Luck <tony.luck@xxxxxxxxx> wrote:
>>> ERMS?
>>
>> It's the fast string extension, aka Enhanced REP MOV STOS.  On CPUs
>> with that feature (and not disabled via MSR), plain ol' rep movs is
>> the fastest way to copy bytes.  I think this includes all Intel CPUs
>> from SNB onwards.
>
> Ah ... very fast at copying .. but currently not machine check recoverable.

Hmm, I assume for the pmem driver I'll want to check at runtime if the
cpu has machine check recovery and fall back to the faster copy if
it's not available?