Re: Tests requiring MD hooks

["Valeriy E. Ushakov" <uwe%stderr.spb.ru@localhost>]

> That seems to be a bit tricky to write in a portable way: testing --x
> right in memory pages requires to put/copy some payload in a page and
> call it.

dlopen something, find a function with dlsym, disable exec on that
page and call the function.  Catch SIGSEGV, check siginfo.  mprotect
it back and call the function again.

-uwe