On 20/09/21 17:06, Christian Borntraeger wrote:

here is a backport for 4.19 of
commit a3e03bc1368 ("KVM: s390: index kvm->arch.idle_mask by vcpu_idx")
This basically removes the kick_mask parts that were introduced with
kernel 5.0 and fixes up the location of the idle_mask to the older
place.

FWIW, it might be a good idea to also backport
8750e72a79dd ("KVM: remember position in kvm->vcpus array") to avoid
a performance regression for large guests (many vCPUs) when this patch
is applied.
@Paolo Bonzini, would you be ok with 8750e72a79dd in older stable releases?

Sure, I suppose you're going to send a separate backport that I can ack.

Paolo