diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -4177,7 +4177,7 @@
 	pmap->pm_cr3 = kernel_pmap->pm_cr3;
 	/* hack to keep pmap_pti_pcid_invalidate() alive */
 	pmap->pm_ucr3 = PMAP_NO_CR3;
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	CPU_ZERO(&pmap->pm_active);
 	TAILQ_INIT(&pmap->pm_pvchunk);
 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
@@ -4398,7 +4398,7 @@
 		break;
 	}
 
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	CPU_ZERO(&pmap->pm_active);
 	TAILQ_INIT(&pmap->pm_pvchunk);
 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
diff --git a/sys/arm64/arm64/pmap.c b/sys/arm64/arm64/pmap.c
--- a/sys/arm64/arm64/pmap.c
+++ b/sys/arm64/arm64/pmap.c
@@ -1748,7 +1748,7 @@
 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
 	pmap->pm_l0_paddr = READ_SPECIALREG(ttbr0_el1);
 	pmap->pm_l0 = (pd_entry_t *)PHYS_TO_DMAP(pmap->pm_l0_paddr);
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	pmap->pm_cookie = COOKIE_FROM(ASID_RESERVED_FOR_PID_0, INT_MIN);
 	pmap->pm_stage = PM_STAGE1;
 	pmap->pm_levels = 4;
@@ -1771,7 +1771,7 @@
 	pmap->pm_l0_paddr = VM_PAGE_TO_PHYS(m);
 	pmap->pm_l0 = (pd_entry_t *)PHYS_TO_DMAP(pmap->pm_l0_paddr);
 
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
 	pmap->pm_cookie = COOKIE_FROM(-1, INT_MAX);
 
diff --git a/sys/arm64/iommu/iommu_pmap.c b/sys/arm64/iommu/iommu_pmap.c
--- a/sys/arm64/iommu/iommu_pmap.c
+++ b/sys/arm64/iommu/iommu_pmap.c
@@ -392,7 +392,7 @@
 	pmap->pm_l0_paddr = VM_PAGE_TO_PHYS(m);
 	pmap->pm_l0 = (pd_entry_t *)PHYS_TO_DMAP(pmap->pm_l0_paddr);
 
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	bzero(&pmap->pm_stats, sizeof(pmap->pm_stats));
 
 	MPASS(levels == 3 || levels == 4);
diff --git a/sys/i386/i386/pmap.c b/sys/i386/i386/pmap.c
--- a/sys/i386/i386/pmap.c
+++ b/sys/i386/i386/pmap.c
@@ -2043,7 +2043,7 @@
 #ifdef PMAP_PAE_COMP
 	pmap->pm_pdpt = IdlePDPT;
 #endif
-	pmap->pm_root.rt_root = 0;
+	vm_radix_init(&pmap->pm_root);
 	CPU_ZERO(&pmap->pm_active);
 	TAILQ_INIT(&pmap->pm_pvchunk);
 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
@@ -2075,7 +2075,7 @@
 		KASSERT(pmap_kextract((vm_offset_t)pmap->pm_pdpt) < (4ULL<<30),
 		    ("pmap_pinit: pdpt above 4g"));
 #endif
-		pmap->pm_root.rt_root = 0;
+		vm_radix_init(&pmap->pm_root);
 	}
 	KASSERT(vm_radix_is_empty(&pmap->pm_root),
 	    ("pmap_pinit: pmap has reserved page table page(s)"));
diff --git a/sys/powerpc/aim/mmu_radix.c b/sys/powerpc/aim/mmu_radix.c
--- a/sys/powerpc/aim/mmu_radix.c
+++ b/sys/powerpc/aim/mmu_radix.c
@@ -4202,7 +4202,7 @@
 
 	for (int j = 0; j <  RADIX_PGD_SIZE_SHIFT; j++)
 		pagezero((vm_offset_t)pmap->pm_pml1 + j * PAGE_SIZE);
-	pmap->pm_radix.rt_root = 0;
+	vm_radix_init(&pmap->pm_radix);
 	TAILQ_INIT(&pmap->pm_pvchunk);
 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
 	pmap->pm_flags = PMAP_PDE_SUPERPAGE;
@@ -4433,7 +4433,7 @@
 	pmap->pm_pml1 = kernel_pmap->pm_pml1;
 	pmap->pm_pid = kernel_pmap->pm_pid;
 
-	pmap->pm_radix.rt_root = 0;
+	vm_radix_init(&pmap->pm_radix);
 	TAILQ_INIT(&pmap->pm_pvchunk);
 	bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
 	kernel_pmap->pm_flags =