Re: [Qemu-devel] [PATCH v1 for-2.12 6/9] s390x/tcg: Implement SIGA instruction

[Cornelia Huck <cohuck@redhat.com>]

On Mon,  4 Dec 2017 15:01:47 +0100
David Hildenbrand <david@redhat.com> wrote:

> I have no idea what that instruction does, but KVM seems to suppress it,
> setting cc=3 (and as it seems to be an io instruction, it should be
> protected). Let's do the same for TCG, so we're at least equal.
> 
> (it is used in the kernel for qdio, I wasn't even able to find the real
>  name of that instruction)

<arcane knowledge from previous life>
It's called SIGNAL ADAPTER, and we don't indicate qdio in the chsc
stuff.
</arcane knowledge from previous life>

Following the KVM lead for undocumented stuff is the way to go,
unsatisfying though it is.

[Don't binutils etc. know the name?]

> 
> Signed-off-by: David Hildenbrand <david@redhat.com>
> ---
>  target/s390x/insn-data.def | 1 +
>  target/s390x/translate.c   | 8 ++++++++
>  2 files changed, 9 insertions(+)