On Fri, 7 Feb 2020 06:39:47 -0500 Christian Borntraeger <borntraeger@xxxxxxxxxx> wrote: > From: Janosch Frank <frankja@xxxxxxxxxxxxx> > > A lot of the registers are controlled by the Ultravisor and never > visible to KVM. Some fields in the sie control block are overlayed, > like gbea. As no userspace uses the ONE_REG interface on s390 it is safe > to disable this for protected guests. Last round, I suggested "As no known userspace uses the ONE_REG interface on s390 if sync regs are available, no functionality is lost if it is disabled for protected guests." Any opinion on that? > > Signed-off-by: Janosch Frank <frankja@xxxxxxxxxxxxx> > Reviewed-by: Thomas Huth <thuth@xxxxxxxxxx> > Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> > [borntraeger@xxxxxxxxxx: patch merging, splitting, fixing] > Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxx> > --- > Documentation/virt/kvm/api.txt | 6 ++++-- > arch/s390/kvm/kvm-s390.c | 3 +++ > 2 files changed, 7 insertions(+), 2 deletions(-)