KVM: s390: pv: avoid stalls for kvm_s390_pv_init_vm

When the system is heavily overcommitted, kvm_s390_pv_init_vm might
generate stall notifications.

Fix this by using uv_call_sched instead of just uv_call. This is ok because
we are not holding spinlocks.

Signed-off-by: Claudio Imbrenda <[email protected]>
Fixes: 214d9bb ("s390/mm: provide memory management functions for protected KVM guests")
Reviewed-by: Christian Borntraeger <[email protected]>
Reviewed-by: Janosch Frank <[email protected]>
Message-Id: <[email protected]>
Signed-off-by: Janosch Frank <[email protected]>
Signed-off-by: Christian Borntraeger <[email protected]>

Author: Claudio Imbrenda

arch/s390/kvm/pv.c

@@ -195,7 +195,7 @@ int kvm_s390_pv_init_vm(struct kvm *kvm, u16 *rc, u16 *rrc)
 	uvcb.conf_base_stor_origin = (u64)kvm->arch.pv.stor_base;
 	uvcb.conf_virt_stor_origin = (u64)kvm->arch.pv.stor_var;
 
-	cc = uv_call(0, (u64)&uvcb);
+	cc = uv_call_sched(0, (u64)&uvcb);
 	*rc = uvcb.header.rc;
 	*rrc = uvcb.header.rrc;
 	KVM_UV_EVENT(kvm, 3, "PROTVIRT CREATE VM: handle %llx len %llx rc %x rrc %x",