On 29.11.18 13:38, Cornelia Huck wrote:
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_strategyThis wants some documentation, I think. How is the admin supposed to know which strategy to choose?
The patch will be dropped. The strategy will not be changeable by an admin. The IAM will never be cleared by the host program during normal operation except for the GISA clear and GISA drop cases.
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(+)
-- Mit freundlichen Grüßen / Kind regards Michael Müller IBM Deutschland Research & Development GmbH Vorsitzender des Aufsichtsrats: Martina Köderitz Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen Registergericht: Amtsgericht Stuttgart, HRB 243294
