KVM: x86/mmu: Use kvm_x86_call() instead of manual static_call()

JIRA: https://issues.redhat.com/browse/RHEL-47242

commit 6a3d704
Author: Sean Christopherson <seanjc@google.com>
Date:   Mon Mar 31 11:27:03 2025 -0700

    KVM: x86/mmu: Use kvm_x86_call() instead of manual static_call()

    Use KVM's preferred kvm_x86_call() wrapper to invoke static calls related
    to mirror page tables.

    No functional change intended.

    Fixes: 77ac707 ("KVM: x86/tdp_mmu: Propagate building mirror page tables")
    Fixes: 94faba8 ("KVM: x86/tdp_mmu: Propagate tearing down mirror page tables")
    Reviewed-by: Kai Huang <kai.huang@intel.com>
    Link: https://lore.kernel.org/r/20250331182703.725214-1-seanjc@google.com
    Signed-off-by: Sean Christopherson <seanjc@google.com>

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>

Author: Maxim Levitsky

arch/x86/kvm/mmu/tdp_mmu.c

@@ -378,7 +378,7 @@ static void remove_external_spte(struct kvm *kvm, gfn_t gfn, u64 old_spte,
 	/* Zapping leaf spte is allowed only when write lock is held. */
 	lockdep_assert_held_write(&kvm->mmu_lock);
 	/* Because write lock is held, operation should success. */
-	ret = static_call(kvm_x86_remove_external_spte)(kvm, gfn, level, old_pfn);
+	ret = kvm_x86_call(remove_external_spte)(kvm, gfn, level, old_pfn);
 	KVM_BUG_ON(ret, kvm);
 }
 
@@ -485,8 +485,8 @@ static void handle_removed_pt(struct kvm *kvm, tdp_ptep_t pt, bool shared)
 	}
 
 	if (is_mirror_sp(sp) &&
-	    WARN_ON(static_call(kvm_x86_free_external_spt)(kvm, base_gfn, sp->role.level,
-							  sp->external_spt))) {
+	    WARN_ON(kvm_x86_call(free_external_spt)(kvm, base_gfn, sp->role.level,
+						    sp->external_spt))) {
 		/*
 		 * Failed to free page table page in mirror page table and
 		 * there is nothing to do further.
@@ -538,12 +538,12 @@ static int __must_check set_external_spte_present(struct kvm *kvm, tdp_ptep_t sp
 	 * external page table, or leaf.
 	 */
 	if (is_leaf) {
-		ret = static_call(kvm_x86_set_external_spte)(kvm, gfn, level, new_pfn);
+		ret = kvm_x86_call(set_external_spte)(kvm, gfn, level, new_pfn);
 	} else {
 		void *external_spt = get_external_spt(gfn, new_spte, level);
 
 		KVM_BUG_ON(!external_spt, kvm);
-		ret = static_call(kvm_x86_link_external_spt)(kvm, gfn, level, external_spt);
+		ret = kvm_x86_call(link_external_spt)(kvm, gfn, level, external_spt);
 	}
 	if (ret)
 		__kvm_tdp_mmu_write_spte(sptep, old_spte);