Re: [PATCH v2 0/3] KVM: s390: Toggle operation exception for userspace

[Eric Farman <farman@linux.ibm.com>]

On Fri, 2026-05-08 at 12:07 +0200, Christian Borntraeger wrote:
> Am 07.05.26 um 22:08 schrieb Eric Farman:
> > Claudio, et al,
> > 
> > Here's an update to the USER_OPEREXEC patch I'd sent the other day.
> > Besides the addition of Claudio's r-b (thank you!), Patch 1 is identical.
> > 
> > Patch 2 contains a couple of new selftests. As it stands, they all run
> > with patch 1 applied, but I put the failing test at the end for if
> > Patch 1 is missing.
> > 
> > Patch 3 is unrelated, but is a minor typo I stumbled on yesterday while
> > looking at this. It seems small enough that a second `git send-email`
> > command seems unnecessary. :)
> > 
> > Eric Farman (3):
> >    KVM: s390: Toggle operation exception for userspace
> >    KVM: s390: selftests: Extended user_operexec tests
> >    KVM: s390: Fix typo in UCONTROL documentation
> > 
> >   Documentation/virt/kvm/api.rst                |   2 +-
> >   arch/s390/kvm/kvm-s390.c                      |   3 +-
> >   .../selftests/kvm/include/s390/facility.h     |   6 +
> >   .../selftests/kvm/s390/user_operexec.c        | 110 ++++++++++++++++++
> >   4 files changed, 119 insertions(+), 2 deletions(-)
> > 
> 
> Independent from this series (which makes sense on its own)
> shouldnt we add another fixup so that we send these kernel injects also to userspace?
> 

Hrm, that's a reasonable idea for the ones in priv.c (intercept.c are already covered, see below).
I'll see if I can find a way to unify (and test) them.

> 
> git grep PGM_OPERATION linux/master arch/s390/kvm/
> linux/master:arch/s390/kvm/intercept.c:         return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);

This is handle_sthyi(), called by handle_operexc(), if stfle.74 is not present.

> linux/master:arch/s390/kvm/intercept.c: return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);

This is handle_operexc(), if neither user_instr0 nor user_operexec are present.

> linux/master:arch/s390/kvm/priv.c:              return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
> linux/master:arch/s390/kvm/priv.c:              return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
> linux/master:arch/s390/kvm/priv.c:              return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
> linux/master:arch/s390/kvm/priv.c:              return kvm_s390_inject_program_int(vcpu, PGM_OPERATION);
> linux/master:arch/s390/kvm/priv.c:              return kvm_s390_inject_program_int(vcpu, PGM_OPERATION)