Now that sub-leaf 1 is handled separately, verify the next sub-leaf is
needed before rejecting KVM_GET_SUPPORTED_CPUID due to an insufficiently
sized userspace array.
Note, although this is technically a bug, it's not visible to userspace
as KVM_GET_SUPPORTED_CPUID is guaranteed to fail on KVM_CPUID_SIGNATURE,
which is hardcoded to be added after leaf 0xD. The real motivation for
the change is to tightly couple the nent/maxnent and do_host_cpuid()
sequences in preparation for future cleanup.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
entry[1].edx = 0;
for (idx = 2, i = 2; idx < 64; ++idx) {
- u64 mask = ((u64)1 << idx);
+ if (!(supported & BIT_ULL(idx)))
+ continue;
if (*nent >= maxnent)
goto out;
do_host_cpuid(&entry[i], function, idx);
- if (entry[i].eax == 0 || !(supported & mask))
+ if (entry[i].eax == 0)
continue;
if (WARN_ON_ONCE(entry[i].ecx & 1))
continue;