KVM: x86: Refactor CPUID 0xD.N sub-leaf entry creation

Increment the number of CPUID entries immediately after do_host_cpuid()
in preparation for moving the logic into do_host_cpuid().  Handle the
rare/impossible case of encountering a bogus sub-leaf by decrementing
the number entries on failure.

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>
This commit is contained in:
Sean Christopherson 2020-03-02 15:56:12 -08:00 committed by Paolo Bonzini
parent 91001d403a
commit 8b2fc445a7

View File

@ -677,6 +677,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function,
goto out;
do_host_cpuid(&entry[i], function, idx);
++*nent;
/*
* The @supported check above should have filtered out
@ -685,12 +686,13 @@ static inline int __do_cpuid_func(struct kvm_cpuid_entry2 *entry, u32 function,
* reach this point, and they should have a non-zero
* save state size.
*/
if (WARN_ON_ONCE(!entry[i].eax || (entry[i].ecx & 1)))
if (WARN_ON_ONCE(!entry[i].eax || (entry[i].ecx & 1))) {
--*nent;
continue;
}
entry[i].ecx = 0;
entry[i].edx = 0;
++*nent;
++i;
}
break;