On Tue, Feb 20, 2018 at 5:05 PM, Luck, Tony <tony.luck@xxxxxxxxx> wrote: >>> EFI[1] stinks. Reading any file in /sys/firmware/efi/efivars/ generates >>> 4 (yes FOUR!) SMIs. > >> Is that actualkly the normal implementation? > > I don't know if there are other implementations. This is what I see on my > lab system. Ok. I'm not a huge fan of EFI. Over-designed to the hilt. Happily at least the loadable drivers are a thing of the past. Do we have a list of things normal users care about? Because one thing that would solve it is caching of the values. We don't want to do that in general, but maybe we could just do it for the subset that we think are "user accessible". Although maybe just that "rate limit" thing would be simplest. I don't want to break existing users, although it's not entirely clear to me if there are any real use cases that matter to users. If tpmtotp is the main case, maybe that can be changed to work around it and just cache a value or something? So I could imagine just applying Joe's / Andy's patch to see if anybody even notices. But if somebody does, we'd have to go to the alternatives anyway. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html