Re: Dealing with the NMI mess

[Peter Zijlstra]

On Fri, Jul 24, 2015 at 03:30:13PM +0200, Peter Zijlstra wrote:
> > > But do we care if we do hit one? The return from the #DB handler can
> > > use a RET. Right?
> 
> Look at do_debug(), it has lovely bits like:
> 
> 	preempt_conditional_sti();
> 
> in it, we do _NOT_ want to be re-enabling interrupts if we're called
> from an !IF context, that'd be _bad_.

Ah, I forgot the conditional thing was the STI depending on regs->flags
& IF..

In any case, better safe than sorry and simply not do #DB ever if !IF.
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