From: Greg Kurz <gr...@kaod.org>
If the host has both KVM PR and KVM HV loaded and we pass:
-machine pseries,accel=kvm,kvm-type=PR
the kvmppc_is_pr() returns false instead of true. Since the helper
is mostly used as fallback, it doesn't have any real impact with
recent kernels. A notable exception is the workaround to allow
migration between compatible hosts with different PVRs (eg, POWER8
and POWER8E), since KVM still doesn't provide a way to check if a
specific PVR is supported (see commit c363a37a450f for details).
According to the official KVM API documentation [1], KVM_PPC_GET_PVINFO
is "vm ioctl", but we check it as a global ioctl. The following function
in KVM is hence called with kvm == NULL and considers we're in HV mode.
int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
{
int r;
/* Assume we're using HV mode when the HV module is loaded */
int hv_enabled = kvmppc_hv_ops ? 1 : 0;
if (kvm) {
/*
* Hooray - we know which VM type we're running on. Depend on
* that rather than the guess above.
*/
hv_enabled = is_kvmppc_hv_enabled(kvm);
}
Let's use kvm_vm_check_extension() to fix the issue.
[1] https://www.kernel.org/doc/Documentation/virtual/kvm/api.txt
Signed-off-by: Greg Kurz <gr...@kaod.org>
Reviewed-by: Thomas Huth <th...@redhat.com>
Signed-off-by: David Gibson <da...@gibson.dropbear.id.au>
---
target/ppc/kvm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 6442dfcb95..1deaf106d2 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -120,7 +120,7 @@ static void kvm_kick_cpu(void *opaque)
static bool kvmppc_is_pr(KVMState *ks)
{
/* Assume KVM-PR if the GET_PVINFO capability is available */
- return kvm_check_extension(ks, KVM_CAP_PPC_GET_PVINFO) != 0;
+ return kvm_vm_check_extension(ks, KVM_CAP_PPC_GET_PVINFO) != 0;
}
static int kvm_ppc_register_host_cpu_type(void);
--
2.13.5
