On Wed, 28 Nov 2018 11:19:43 +0100 Michael Mueller <mimu@xxxxxxxxxxxxx> wrote: > The sysctl file /proc/sys/s390/iam_clear_strategy defines under which > condition the GISA IAM is cleared before entering the SIE in routine > vcpu_pre_run(). > > The following IAM clear strategies are available: > > 0 : the mask is never cleared > 1 : the mask is cleared if I/O interruptions are not > disabled by the PSW of the vcpu entering the SIE > 2 : the mask is unconditionally cleared > > The default IAM clear strategy after system boot is 0. > > Set the new strategy by means of the sysctl command or write to the file. > > sysctl s390.iam_clear_strategy=1 > echo 2 >/proc/sys/s390/iam_clear_strategy This wants some documentation, I think. How is the admin supposed to know which strategy to choose? > > Signed-off-by: Michael Mueller <mimu@xxxxxxxxxxxxx> > --- > arch/s390/kvm/interrupt.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++ > arch/s390/kvm/kvm-s390.c | 1 + > arch/s390/kvm/kvm-s390.h | 1 + > 3 files changed, 71 insertions(+)