Re: [PATCH] Pentium Pro - sysenter - doublefault

[Jamie Lokier <jamie@shareable.org>]

Richard Curnow wrote:
> OK, since I get something different to the other reports I saw:
> 
>  1:20PM-malvern-0-534-% ./sysenter
>  1:20PM-malvern-STKFLT-535-% echo $?
> 144

Hi Richard,

That's because you ran it on a 2.5/2.6 kernel, right?  The test code
is meant for 2.4 kernels and earlier :)

Here is a more universal test:

	int main () {
		asm ("movl %%esp,%%ebp;sysenter" : : "a" (1), "b" (0));
		return 0;
	}

I expect it to do the first of these which is applicable:

	- raise SIGILL on Pentium and earlier Intel CPUs
	- raise SIGILL on non-Intel CPUs which don't have the SEP capability
	- raise SIGSEGV on Pentium Pro CPUs
	- raise SIGSEGV on Pentium II CPUs with model == 3 and stepping < 3
	- raise SIGSEGV on 2.4 kernels
	- exit with status 0 on 2.6 kernels

Enjoy,
-- Jamie