Re: [ARCH question] Do syscall_get_nr and syscall_get_arguments always work?
On Fri, Feb 7, 2014 at 4:58 AM, Jonas Bonn <jonas.bonn(a)gmail.com> wrote:
Hi Andy,
On 5 February 2014 00:50, Andy Lutomirski <luto(a)amacapital.net> wrote:
>
> I can't even find the system call entry point on mips.
>
>
> Is there a semi-official answer here?
I don't have an official answer for you, but when I wanted to do
something with these entry points a couple of years back I discovered
that they aren't very thoroughly implemented across the various
architectures. I started cleaning this up and can probably dig up
some of this for you if you need it.
The syscall_get_xyz functions are certainly implemented and functional
in all relevant architectures -- the audit code is already using them.
The thing I'm uncertain about is whether they are usable with no
syscall slow path bits set.
I guess that, if the syscall restart logic needs to read the argument
registers, then they're probably reliably saved...
--Andy