[RFC 5/5] x86,seccomp: Add a seccomp fastpath

[H. Peter Anvin]

On 06/11/2014 03:22 PM, Andy Lutomirski wrote:
> On Wed, Jun 11, 2014 at 3:18 PM, H. Peter Anvin <hpa at zytor.com> wrote:
>> On 06/11/2014 02:56 PM, Andy Lutomirski wrote:
>>>
>>> 13ns is with the simplest nonempty filter.  I hope that empty filters
>>> don't work.
>>>
>>
>> Why wouldn't they?
> 
> Is it permissible to fall off the end of a BPF program?  I'm getting
> EINVAL trying to install an actual empty filter.  The filter I tested
> with was:
> 

What I meant was that there has to be a well-defined behavior for the
program falling off the end anyway, and that that should be preserved.

I guess it is possible to require that all code paths must provably
reach a termination point.

	-hpa