Re: [RFC][PATCH] PM: Warn if interrupts are enabled during suspend-resume of sysdevs

[Ingo Molnar <mingo@elte.hu>]

* Rafael J. Wysocki <rjw@sisk.pl> wrote:

> From: Rafael J. Wysocki <rjw@sisk.pl>
> 
> Sysdev have to be suspended and resumed with interrupts disabled 
> and things usually break in a way that's difficult to debug if one 
> of sysdev drivers enables interrupts by mistake during suspend or 
> resume.  Add extra checks that will generate warnings in such 
> cases.

no objections - but obviously the real solution would be to finish 
PeterZ's "detect assymetric kernel functions" patch:

That patch (Peter posted an initial version of it already on lkml) 
works the following way:

the ftrace function-graph-tracer plugin is utilized to instrument 
every function call in the kernel. That is extended with the 
following check: every function except __lockfunc and __sched 
functions must be 'balanced' - i.e. they must enter and exit with 
the same IRQ flags, preempt count and lock depth counter.

	Ingo