[PATCH v3 06/13] um: nommu: syscalls handler from userspace by seccomp filter

[Johannes Berg]

On Thu, 2024-12-05 at 22:51 +0900, Hajime Tazaki wrote:
> > 
> > I don't understand why this behaves differently with and without
> > zpoline, it seems it shouldn't need to. Anyway, still think zpoline is
> > future work.
> 
> I will remove the zpoline part.
> When zpoline is used, SIGSYS signal is a sign of unexpected syscall
> invocation, and raise this signal to userspace (with printing
> message).
> 

But why? We already established that zpoline cannot translate
everything, e.g. JIT code and similar. So even if you have zpoline you
can just have seccomp handle the syscall as a fallback, to catch cases
like that rather than failing, no?

johannes