kvm: work around supported cpuid ioctl() brokenness
KVM_GET_SUPPORTED_CPUID has been known to fail to return -E2BIG
when it runs out of entries. Detect this by always trying again
with a bigger table if the ioctl() fills the table.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/target-i386/kvm.c b/target-i386/kvm.c
index 5b52de3..eb61598 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -44,6 +44,9 @@
cpuid = (struct kvm_cpuid2 *)qemu_mallocz(size);
cpuid->nent = max;
r = kvm_ioctl(s, KVM_GET_SUPPORTED_CPUID, cpuid);
+ if (r == 0 && cpuid->nent >= max) {
+ r = -E2BIG;
+ }
if (r < 0) {
if (r == -E2BIG) {
qemu_free(cpuid);