[PATCH 1/1] arm64: Add initial set of stack unwinder self tests

[Ivan T. Ivanov]

Hi,

On 06-29 16:59, Mark Brown wrote:
> 
> On Fri, Jun 24, 2022 at 05:10:00PM +0300, Ivan T. Ivanov wrote:
> > Add kunit tests for obvious cases where stack unwind could be needed.
> > Like these:
> > 
> >  * Unwind a separate task
> >  * Unwind starting from caller
> >  * Unwind from irq context
> >  * Unwind from kprobe handler called via ftrace
> >  * Unwind from ftrace handler
> >  * Unwind through kretprobed function
> >  * Unwind from kretprobe handler
> > 
> > Tests are completely based on code used in s390 unwinder tests.
> > Cases which where not relevant to aarch64 where removed and
> > some places where adjusted to address aarch64 specifics.
> 
> I think this would be a bit easier to digest if it were a series which
> builds things up with the test cases in individual patches, or at least
> things like ftrace and kprobes split out a bit more, rather than every
> single test all at once.  I've got a few *very* superficial comments
> below, I think the code is fine but there's several moving pieces to
> check.

Ok. I will split and resend.

> 
> > +/*
> > + * Calls test_arch_stack_walk() which is handy wrapper of aarch64 unwind
> > + * functionality, and verifies that the result contains unwindme_func2
> > + *followed by unwindme_func1.
> 
> Missing space.

Sure.

> 
> > +	ret = register_ftrace_function(fops);
> > +	if (!ret) {
> > +		ret = test_unwind_ftraced_func(u);
> > +		unregister_ftrace_function(fops);
> > +	} else {
> > +		kunit_err(current_test,
> > +			  "failed to register ftrace handler (%d)\n", ret);
> > +	}
> 
> Shouldn't we return an error here?

Error will be returned once we remove test_unwind_ftraced_func
address from ftrace filters.

Regards,
Ivan