On Tue, 29 Apr 2014 15:05:55 +0200 (CEST) Jiri Kosina <[email protected]> wrote:
> According to 38.4 of [1], when SMM mode is entered while the CPU is > handling NMI, the end result might be that upon exit from SMM, NMIs will > be re-enabled and latched NMI delivered as nested [2]. Note, if this were true, then the x86_64 hardware would be extremely buggy. That's because NMIs are not made to be nested. If SMM's come in during an NMI and re-enables the NMI, then *all* software would break. That would basically make NMIs useless. The only time I've ever witness problems (and I stress NMIs all the time), is when the NMI itself does a fault. Which my patch set handles properly. I've also stressed this on boxes that do have SMIs and SMMs. Now, you can have a bad BIOS that does re-enable NMIs from SMMs or SMIs, but then you need to take that up with your vendor. -- Steve -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
