[PATCH v4 06/22] aarch64: Add GCS support to vfork

[Wilco Dijkstra]

Hi Richard,

>> OK. Always use br in child.
>
> Has this been tested on targets that use BTI?  RET will bypass BTI
> checking, but BR will not, so if the caller has not put a BTI
> instruction after the call this will crash.

GCC will insert BTI after calls that may return differently. Setjmp and vfork
are some examples (they are internally marked as returns_twice).

Cheers,
Wilco