From: Mark McLoughlin Subject: [PATCH] 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 Signed-off-by: Avi Kivity --- kvm/libkvm/libkvm-x86.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/kvm/libkvm/libkvm-x86.c b/kvm/libkvm/libkvm-x86.c index a2f6320..4f9539a 100644 --- a/kvm/libkvm/libkvm-x86.c +++ b/kvm/libkvm/libkvm-x86.c @@ -575,6 +575,8 @@ static struct kvm_cpuid2 *try_get_cpuid(kvm_context_t kvm, int max) r = ioctl(kvm->fd, KVM_GET_SUPPORTED_CPUID, cpuid); if (r == -1) r = -errno; + else if (r == 0 && cpuid->nent >= max) + r = -E2BIG; if (r < 0) { if (r == -E2BIG) { free(cpuid); -- 1.6.0.6