KVM: x86: Make "external SPTE" ops that can fail RET0 static calls

Define kvm_x86_ops .link_external_spt(), .set_external_spte(), and
.free_external_spt() as RET0 static calls so that an unexpected call to a
a default operation doesn't consume garbage.

Fixes: 77ac7079e66d ("KVM: x86/tdp_mmu: Propagate building mirror page tables")
Fixes: 94faba8999b9 ("KVM: x86/tdp_mmu: Propagate tearing down mirror page tables")
Reviewed-by: Kai Huang <kai.huang@intel.com>
Reviewed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Link: https://patch.msgid.link/20260129011517.3545883-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index e4fca997ec797b7eada9e3e79df502c063acaa9a..b0269325646cbc194f89409a03fa28ef8220d23b 100644 (file)
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -96,9 +96,9 @@ KVM_X86_OP_OPTIONAL_RET0(set_identity_map_addr)
 KVM_X86_OP_OPTIONAL_RET0(get_mt_mask)
 KVM_X86_OP_OPTIONAL_RET0(tdp_has_smep)
 KVM_X86_OP(load_mmu_pgd)
-KVM_X86_OP_OPTIONAL(link_external_spt)
-KVM_X86_OP_OPTIONAL(set_external_spte)
-KVM_X86_OP_OPTIONAL(free_external_spt)
+KVM_X86_OP_OPTIONAL_RET0(link_external_spt)
+KVM_X86_OP_OPTIONAL_RET0(set_external_spte)
+KVM_X86_OP_OPTIONAL_RET0(free_external_spt)
 KVM_X86_OP_OPTIONAL(remove_external_spte)
 KVM_X86_OP(has_wbinvd_exit)
 KVM_X86_OP(get_l2_tsc_offset)