[PATCH 1/2] KVM: x86/mmu: Wrap kvm_mmu_zap_all_fast TDP MMU code in ifdefs

[Ben Gardon]

The TDP MMU code in kvm_mmu_zap_all_fast is only needed with
CONFIG_X86_64 and creates a build error without that setting. Since the
TDP MMU can only be enabled with CONFIG_X86_64, wrap those code blocks
in ifdefs.

Fixes: 1336c692abad ("KVM: x86/mmu: Fast invalidation for TDP MMU")

Reported-by: kernel test robot <l...@intel.com>
Signed-off-by: Ben Gardon <bgar...@google.com>
---
 arch/x86/kvm/mmu/mmu.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 0f311c9bf9c6..3ae59c8e129b 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -5407,7 +5407,9 @@ static void kvm_zap_obsolete_pages(struct kvm *kvm)
  */
 static void kvm_mmu_zap_all_fast(struct kvm *kvm)
 {
+#ifdef CONFIG_X86_64
        struct kvm_mmu_page *root;
+#endif /* CONFIG_X86_64 */
 
        lockdep_assert_held(&kvm->slots_lock);
 
@@ -5424,6 +5426,7 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
        kvm->arch.mmu_valid_gen = kvm->arch.mmu_valid_gen ? 0 : 1;
 
 
+#ifdef CONFIG_X86_64
        if (is_tdp_mmu_enabled(kvm)) {
                /*
                 * Mark each TDP MMU root as invalid so that other threads
@@ -5456,6 +5459,7 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
                        if (refcount_inc_not_zero(&root->tdp_mmu_root_count))
                                root->role.invalid = true;
        }
+#endif /* CONFIG_X86_64 */
 
        /*
         * Notify all vcpus to reload its shadow page table and flush TLB.
@@ -5471,11 +5475,13 @@ static void kvm_mmu_zap_all_fast(struct kvm *kvm)
 
        write_unlock(&kvm->mmu_lock);
 
+#ifdef CONFIG_X86_64
        if (is_tdp_mmu_enabled(kvm)) {
                read_lock(&kvm->mmu_lock);
                kvm_tdp_mmu_zap_invalidated_roots(kvm);
                read_unlock(&kvm->mmu_lock);
        }
+#endif /* CONFIG_X86_64 */
 }
 
 static bool kvm_has_zapped_obsolete_pages(struct kvm *kvm)
-- 
2.31.1.368.gbe11c130af-goog