x86/CPUID: suppress IOMMU related hypervisor leaf data

Now that the IOMMU for guests can't be enabled "on demand" anymore,
there's also no reason to expose the related CPUID bit "just in case".

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index bc5b8f8ea3975a28e86b27f0aa7f68a5a17e6fbe..c27dd4cd4390b345875e1d558f9ec64d63ea1383 100644 (file)
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -1050,7 +1050,8 @@ void cpuid_hypervisor_leaves(const struct vcpu *v, uint32_t leaf,
          * Indicate that memory mapped from other domains (either grants or
          * foreign pages) has valid IOMMU entries.
          */
-        res->a |= XEN_HVM_CPUID_IOMMU_MAPPINGS;
+        if ( is_iommu_enabled(d) )
+            res->a |= XEN_HVM_CPUID_IOMMU_MAPPINGS;
 
         /* Indicate presence of vcpu id and set it in ebx */
         res->a |= XEN_HVM_CPUID_VCPU_ID_PRESENT;