From: Mark McLoughlin <markmc@redhat.com>
Date: Wed, 20 May 2009 18:36:18 +0000 (-0300)
Subject: kvm: work around supported cpuid ioctl() brokenness
X-Git-Tag: v0.10.5~1
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=0926c7a4e5abd3cfebec3a6e35617730577ce932;p=thirdparty%2Fqemu.git

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 5b52de34dd6..eb615989ea0 100644
--- a/target-i386/kvm.c
+++ b/target-i386/kvm.c
@@ -44,6 +44,9 @@ static struct kvm_cpuid2 *try_get_cpuid(KVMState *s, int max)
     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);