diff --git a/mypy.ini b/mypy.ini
--- a/mypy.ini
+++ b/mypy.ini
@@ -24,6 +24,9 @@
 [mypy-django.*]
 ignore_missing_imports = True
 
+[mypy-multiprocessing.util]
+ignore_missing_imports = True
+
 [mypy-pkg_resources.*]
 ignore_missing_imports = True
 
@@ -33,6 +36,9 @@
 [mypy-pytest.*]
 ignore_missing_imports = True
 
+[mypy-pytest_cov.*]
+ignore_missing_imports = True
+
 [mypy-pytest_kafka.*]
 ignore_missing_imports = True
 
diff --git a/swh/storage/tests/conftest.py b/swh/storage/tests/conftest.py
--- a/swh/storage/tests/conftest.py
+++ b/swh/storage/tests/conftest.py
@@ -5,16 +5,21 @@
 
 import glob
 import pytest
-
+import multiprocessing.util
 from typing import Union
 
-from pytest_postgresql import factories
-from pytest_postgresql.janitor import DatabaseJanitor, psycopg2, Version
-
 from os import path, environ
 from hypothesis import settings
 from typing import Dict
 
+try:
+    import pytest_cov.embed
+except ImportError:
+    pytest_cov = None
+
+from pytest_postgresql import factories
+from pytest_postgresql.janitor import DatabaseJanitor, psycopg2, Version
+
 import swh.storage
 
 from swh.core.utils import numfile_sortkey as sortkey
@@ -54,6 +59,21 @@
 settings.register_profile("slow", max_examples=20, deadline=5000)
 
 
+if pytest_cov is not None:
+    # pytest_cov + multiprocessing can cause a segmentation fault when starting
+    # the child process <https://forge.softwareheritage.org/P706>; so we're
+    # removing pytest-coverage's hook that runs when a child process starts.
+    # This means code run in child processes won't be counted in the coverage
+    # report, but this is not an issue because the only code that runs only in
+    # child processes is the RPC server.
+    for (key, value) in multiprocessing.util._afterfork_registry.items():
+        if value is pytest_cov.embed.multiprocessing_start:
+            del multiprocessing.util._afterfork_registry[key]
+            break
+    else:
+        assert False, "missing pytest_cov.embed.multiprocessing_start?"
+
+
 @pytest.fixture
 def swh_storage_backend_config(postgresql_proc, swh_storage_postgresql):
     yield {