From: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> commit 3ae11dbcfac906a8c3a480e98660a823130dc16a upstream. The switch to a keyed guest does not require a classic sske as the other guest CPUs are not accessing the key before the switch is complete. By using the NQ SSKE things are faster especially with multiple guests. Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> Suggested-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220530092706.11637-3-borntraeger@xxxxxxxxxxxxx Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/mm/pgtable.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -734,7 +734,7 @@ void ptep_zap_key(struct mm_struct *mm, pgste_val(pgste) |= PGSTE_GR_BIT | PGSTE_GC_BIT; ptev = pte_val(*ptep); if (!(ptev & _PAGE_INVALID) && (ptev & _PAGE_WRITE)) - page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 1); + page_set_storage_key(ptev & PAGE_MASK, PAGE_DEFAULT_KEY, 0); pgste_set_unlock(ptep, pgste); preempt_enable(); }
