On Fri, 29 Apr 2016, Andy Lutomirski wrote:

quoted

NMI, MCE and interrupts aren't a problem because they have dedicated
stacks, which are easy to detect.  If the tasks' stack is on an
exception stack or an irq stack, we consider it unreliable.

Only on x86_64.

Well, MCEs are more or less x86-specific as well. But otherwise good 
point, thanks Andy.

So, how does stack layout generally look like in case when NMI is actually 
running on proper kernel stack? I thought it's guaranteed to contain 
pt_regs anyway in all cases. Is that not guaranteed to be the case?

Thanks,

-- 
Jiri Kosina
SUSE Labs