Re: [RFC PATCH v1 00/13] exec: add spawn templates for repeated executable startup

On Thu, May 28, 2026 at 01:02:53PM +0200, Christian Brauner wrote:
> On Thu, May 28, 2026 at 05:52:21PM +0800, Li Chen wrote:
> > Hi,
> > 
> > This is an early RFC for an idea that is probably still rough in both the
> > UAPI and implementation details. Sorry for the rough edges; I am sending
> > it now to check whether this direction is worth pursuing and to get
> > feedback on the kernel/userspace boundary.
> 
> The idea of having a builder api for exec isn't all that crazy. But it
> should simply be built on top of pidfds and thus pidfs itself instead.
> It has all the basic infrastructure in place already. Any implementation
> should also allow userspace to implement posix_spawn() on top of it.
> 
> fd = pidfd_open(0, PIDFD_EMPTY /* or better name */)
> 
> pidfd_config(fd, ...) // modeled similar to fsconfig()

FWIW, I agree this should be modelled after fsconfig and built on pidfs.
Doing so will avoid a bunch of design issues, etc.

-Kees

-- 
Kees Cook