Re: [RFC] x86_64: A real proposal for iret-less return to kernel

From: H. Peter Anvin
Date: Wed May 21 2014 - 17:46:42 EST


Adding Tony.

On 05/21/2014 02:43 PM, Borislav Petkov wrote:
> On Thu, May 22, 2014 at 06:37:26AM +0900, Linus Torvalds wrote:
>> Seriously. If an NMI is interrupted by an MCE, you might as well
>> consider the machine dead. Don't worry about it. We may or may not
>> recover, but it is *not* our problem.
>
> I certainly like this way of handling it. We can even issue a nice
> banner saying something like "You're f*cked - go change hw."
>

Actually, it would be a lot better to panic than deadlock (HA systems
tend to have something in place to catch the panic and/or reboot). Any
way we can see if the CPU is already holding that lock and panic in that
case?

-hpa


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/