diff --git a/Makefile b/Makefile
index 7874b44e..5e3be67b 100644
--- a/Makefile
+++ b/Makefile
@@ -10,12 +10,13 @@ test:
 	pytest tests/ -W ignore::DeprecationWarning -v --tb=short -m "not verifier"
 
 test-cov:
-	pytest tests/ -v --tb=short -m "not verifier" \
+	pytest tests/ -W ignore::DeprecationWarning -v --tb=short -m "not verifier" \
 		--cov=pythonbpf --cov-report=term-missing --cov-report=html
 
 test-verifier:
-	@echo "NOTE: verifier tests require sudo and bpftool. Uses sudo .venv/bin/python3."
-	pytest tests/test_verifier.py -v --tb=short -m verifier
+	@echo "NOTE: verifier tests shell out to 'sudo bpftool'; run 'sudo -v' first so"
+	@echo "      the timestamp does not lapse mid-run. bpftool must be installed."
+	pytest tests/test_verifier.py -W ignore::DeprecationWarning -v --tb=short -m verifier
 
 all: clean install
 
diff --git a/pythonbpf/maps/maps_pass.py b/pythonbpf/maps/maps_pass.py
index 083b24a6..ca078454 100644
--- a/pythonbpf/maps/maps_pass.py
+++ b/pythonbpf/maps/maps_pass.py
@@ -175,10 +175,15 @@ def process_bpf_map(func_node, compilation_context):
 
     if isinstance(rval, ast.Call) and isinstance(rval.func, ast.Name):
         handler = MapProcessorRegistry.get_processor(rval.func.id)
-        if handler:
-            return handler(map_name, rval, compilation_context)
-        else:
-            logger.warning(f"Unknown map type {rval.func.id}, defaulting to HashMap")
-            return process_hash_map(map_name, rval, compilation_context)
+        if handler is None:
+            # Raise an exception and fail the build because the
+            # map carried the wrong type. A misspelled map type
+            # is a program error.
+            known = ", ".join(sorted(MapProcessorRegistry.known_types()))
+            raise ValueError(
+                f"Unknown map type '{rval.func.id}' returned by '{map_name}'. "
+                f"Known map types: {known}"
+            )
+        return handler(map_name, rval, compilation_context)
     else:
         raise ValueError("Function under @map must return a map")
diff --git a/pythonbpf/maps/maps_utils.py b/pythonbpf/maps/maps_utils.py
index 194b408e..a271697c 100644
--- a/pythonbpf/maps/maps_utils.py
+++ b/pythonbpf/maps/maps_utils.py
@@ -33,3 +33,8 @@ def decorator(func):
     def get_processor(cls, map_type_name):
         """Get the processor function for a map type"""
         return cls._processors.get(map_type_name)
+
+    @classmethod
+    def known_types(cls):
+        """Names of every registered map type, for error messages"""
+        return list(cls._processors.keys())
diff --git a/tests/README.md b/tests/README.md
index 2861f4f3..6b63fd45 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -69,8 +69,16 @@ Known-broken tests are declared in `tests/test_config.toml`:
 "failing_tests/my_test.py" = {reason = "...", level = "ir"}
 ```
 
-- `level = "ir"` — fails during IR generation; both IR and LLC tests are marked xfail.
-- `level = "llc"` — IR generates fine but `llc` rejects it; only the LLC test is marked xfail.
+- `level = "ir"` — fails during IR generation.
+- `level = "llc"` — IR generates fine but `llc` rejects it.
+- `level = "verifier"` — IR and `llc` both succeed, but the kernel verifier rejects the object.
+
+A failure at one level implies failure at every later one, so the declared level marks
+that level **and all later ones** xfail. An `"ir"` entry is xfail at all three levels; a
+`"verifier"` entry is xfail at level 3 only and must still pass levels 1 and 2.
+
+Every test file runs at every level, including the ones declared here — level 3 does not
+skip declared failures, it reports them as expected ones.
 
 All xfails use `strict = True`: if a test starts **passing** it shows up as **XPASS** and is treated as a test failure. This is intentional — it means the bug was fixed and the test should be promoted to `passing_tests/`.
 
diff --git a/tests/conftest.py b/tests/conftest.py
index ce92d1dd..42ab30ed 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -19,6 +19,7 @@
 
 import pytest
 
+from tests.framework.bpf_test_case import level_index
 from tests.framework.collector import collect_all_test_files
 
 # ── vmlinux availability ────────────────────────────────────────────────────
@@ -70,14 +71,19 @@ def pytest_collection_modifyitems(items):
 
         # xfail (strict: XPASS counts as a test failure, alerting us to fixed bugs)
         if case.is_expected_fail:
-            # Level "ir" → fails at IR generation: xfail both IR and LLC tests
-            # Level "llc" → IR succeeds but LLC fails: only xfail the LLC test
-            is_llc_test = item.nodeid.startswith("tests/test_llc_compilation.py")
-
-            apply_xfail = (case.xfail_level == "ir") or (
-                case.xfail_level == "llc" and is_llc_test
-            )
-            if apply_xfail:
+            # A failure at one level implies failure at every later one, so mark
+            # this item xfail whenever the declared level is at or before it:
+            #   "ir"       → IR, LLC and verifier
+            #   "llc"      → LLC and verifier (IR is expected to succeed)
+            #   "verifier" → verifier only
+            if item.nodeid.startswith("tests/test_verifier.py"):
+                item_level = "verifier"
+            elif item.nodeid.startswith("tests/test_llc_compilation.py"):
+                item_level = "llc"
+            else:
+                item_level = "ir"
+
+            if level_index(case.xfail_level) <= level_index(item_level):
                 item.add_marker(
                     pytest.mark.xfail(
                         reason=case.xfail_reason,
diff --git a/tests/framework/bpf_test_case.py b/tests/framework/bpf_test_case.py
index d80a7134..a993166e 100644
--- a/tests/framework/bpf_test_case.py
+++ b/tests/framework/bpf_test_case.py
@@ -1,6 +1,20 @@
 from dataclasses import dataclass
 from pathlib import Path
 
+# The three test levels, in pipeline order. A test declared as failing at one
+# level is also expected to fail at every later level: a program that cannot
+# generate IR cannot reach llc, and one that llc rejects never reaches the
+# kernel. Used by conftest to decide which items to mark xfail.
+LEVELS = ("ir", "llc", "verifier")
+
+
+def level_index(level: str) -> int:
+    """Position of a level in the pipeline. Unknown levels sort first ("ir")."""
+    try:
+        return LEVELS.index(level)
+    except ValueError:
+        return 0
+
 
 @dataclass
 class BpfTestCase:
@@ -8,7 +22,7 @@ class BpfTestCase:
     rel_path: str
     is_expected_fail: bool = False
     xfail_reason: str = ""
-    xfail_level: str = "ir"  # "ir" or "llc"
+    xfail_level: str = "ir"  # one of LEVELS
     needs_vmlinux: bool = False
     skip_reason: str = ""
 
diff --git a/tests/failing_tests/if.py b/tests/passing_tests/if.py
similarity index 84%
rename from tests/failing_tests/if.py
rename to tests/passing_tests/if.py
index 638c2ce3..8949d253 100644
--- a/tests/failing_tests/if.py
+++ b/tests/passing_tests/if.py
@@ -3,7 +3,7 @@
 
 
 @bpf
-@section("sometag1")
+@section("tracepoint/syscalls/sys_enter_execve")
 def sometag(ctx: c_void_p) -> c_int64:
     if 3 + 2 == 5:
         return c_int64(5)
diff --git a/tests/passing_tests/return.py b/tests/passing_tests/return.py
index 9bd048b6..67a0bb05 100644
--- a/tests/passing_tests/return.py
+++ b/tests/passing_tests/return.py
@@ -3,7 +3,7 @@
 
 
 @bpf
-@section("sometag1")
+@section("tracepoint/syscalls/sys_enter_execve")
 def sometag(ctx: c_void_p) -> c_int64:
     return c_int64(1 - 1)
 
diff --git a/tests/passing_tests/ringbuf.py b/tests/passing_tests/ringbuf.py
index 0566d855..05652cf1 100644
--- a/tests/passing_tests/ringbuf.py
+++ b/tests/passing_tests/ringbuf.py
@@ -1,13 +1,13 @@
 from pythonbpf import bpf, BPF, map, bpfglobal, section, compile, compile_to_ir
-from pythonbpf.maps import RingBuf, HashMap
+from pythonbpf.maps import RingBuffer, HashMap
 from ctypes import c_int32, c_void_p
 
 
 # Define a map
 @bpf
 @map
-def mymap() -> RingBuf:
-    return RingBuf(max_entries=(1024))
+def mymap() -> RingBuffer:
+    return RingBuffer(max_entries=4096)
 
 
 @bpf
diff --git a/tests/passing_tests/var_rval.py b/tests/passing_tests/var_rval.py
index ee1735e7..0742c040 100644
--- a/tests/passing_tests/var_rval.py
+++ b/tests/passing_tests/var_rval.py
@@ -5,7 +5,7 @@
 
 
 @bpf
-@section("sometag1")
+@section("tracepoint/syscalls/sys_enter_execve")
 def sometag(ctx: c_void_p) -> c_int64:
     a = 1 - 1
     return c_int64(a)
diff --git a/tests/test_config.toml b/tests/test_config.toml
index edcd90ce..8a6255a3 100644
--- a/tests/test_config.toml
+++ b/tests/test_config.toml
@@ -2,15 +2,27 @@
 #
 # [xfail]  — tests expected to fail.
 #   key   = path relative to tests/
-#   value = {reason = "...", level = "ir" | "llc"}
-#     level "ir"  = fails during pythonbpf IR generation (exception or ERROR log)
-#     level "llc" = IR generates but llc rejects it
+#   value = {reason = "...", level = "ir" | "llc" | "verifier"}
+#     level "ir"       = fails during pythonbpf IR generation (exception or ERROR log)
+#     level "llc"      = IR generates but llc rejects it
+#     level "verifier" = IR and llc both succeed, but the kernel verifier rejects it
+#
+# A failure at one level implies failure at every later one, so the declared
+# level marks that level and all later ones xfail.
 #
 
 [xfail]
 
 "failing_tests/conditionals/struct_ptr.py" = {reason = "Struct pointer used directly as boolean condition not supported", level = "ir"}
 
+# Compiles cleanly; rejected by the kernel. The `data + 34 < data_end` guard is
+# emitted as a signed compare over values round-tripped through the stack, so the
+# verifier never narrows the packet range (it stays r=0) and the later
+# `iph.saddr` read fails with "invalid access to packet, off=26 size=4" /
+# "R1 offset is outside of the packet". Direct packet access needs bounds checks
+# in a form the verifier can follow.
+"failing_tests/xdp/xdp_test_1.py" = {reason = "XDP direct packet access: the data/data_end guard does not establish a packet range the verifier can use", level = "verifier"}
+
 "failing_tests/license.py" = {reason = "Missing LICENSE global produces IR that llc rejects — should be caught earlier with a clear error message", level = "llc"}
 
 "failing_tests/undeclared_values.py" = {reason = "Undeclared variable used in f-string — should raise SyntaxError (correct behaviour, test documents it)", level = "ir"}
diff --git a/tests/test_verifier.py b/tests/test_verifier.py
index 413ef453..3966e3f6 100644
--- a/tests/test_verifier.py
+++ b/tests/test_verifier.py
@@ -24,12 +24,12 @@
 from tests.framework.verifier import verify_object
 
 
-def _passing_test_files():
-    return [c.path for c in collect_all_test_files() if not c.is_expected_fail]
+def _verifier_test_files():
+    return [c.path for c in collect_all_test_files()]
 
 
-def _passing_test_ids():
-    return [c.rel_path for c in collect_all_test_files() if not c.is_expected_fail]
+def _verifier_test_ids():
+    return [c.rel_path for c in collect_all_test_files()]
 
 
 def _get_rejection_reason(verifier_test_file: Path, output) -> str:
@@ -43,11 +43,16 @@ def _get_rejection_reason(verifier_test_file: Path, output) -> str:
     return errstr
 
 
+# Every test file runs at this level, including the ones declared in
+# test_config.toml. conftest marks those xfail, so an "ir"- or "llc"-level
+# failure is still reported as an expected failure rather than being silently
+# dropped from the level-3 run — and a "verifier"-level entry becomes possible
+# at all.
 @pytest.mark.verifier
 @pytest.mark.parametrize(
     "verifier_test_file",
-    _passing_test_files(),
-    ids=_passing_test_ids(),
+    _verifier_test_files(),
+    ids=_verifier_test_ids(),
 )
 def test_kernel_verifier(verifier_test_file: Path, tmp_path, caplog):
     """Compile the BPF test and verify it passes the kernel verifier."""