spapr: fix the value of SDR1 in kvmppc_put_books_sregs()

When running with KVM PR, if a new HPT is allocated we need to inform
KVM about the HPT address and size. This is currently done by hacking
the value of SDR1 and pushing it to KVM in several places.

Also, migration breaks the guest since it is very unlikely the HPT has
the same address in source and destination, but we push the incoming
value of SDR1 to KVM anyway.

This patch introduces a new virtual hypervisor hook so that the spapr
code can provide the correct value of SDR1 to be pushed to KVM each
time kvmppc_put_books_sregs() is called.

It allows to get rid of all the hacking in the spapr/kvmppc code and
it fixes migration of nested KVM PR.

Suggested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Greg Kurz <groug@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 14 insertions, 0 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 0ce3ec87ac..ff87f155d5 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1240,6 +1240,19 @@ static hwaddr spapr_hpt_mask(PPCVirtualHypervisor *vhyp)
     return HTAB_SIZE(spapr) / HASH_PTEG_SIZE_64 - 1;
 }
 
+static target_ulong spapr_encode_hpt_for_kvm_pr(PPCVirtualHypervisor *vhyp)
+{
+    sPAPRMachineState *spapr = SPAPR_MACHINE(vhyp);
+
+    assert(kvm_enabled());
+
+    if (!spapr->htab) {
+        return 0;
+    }
+
+    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
+}
+
 static const ppc_hash_pte64_t *spapr_map_hptes(PPCVirtualHypervisor *vhyp,
                                                 hwaddr ptex, int n)
 {
@@ -3604,6 +3617,7 @@ static void spapr_machine_class_init(ObjectClass *oc, void *data)
     vhc->unmap_hptes = spapr_unmap_hptes;
     vhc->store_hpte = spapr_store_hpte;
     vhc->get_patbe = spapr_get_patbe;
+    vhc->encode_hpt_for_kvm_pr = spapr_encode_hpt_for_kvm_pr;
     xic->ics_get = spapr_ics_get;
     xic->ics_resend = spapr_ics_resend;
     xic->icp_get = spapr_icp_get;