[PATCH blktests] nvme/070: add multipath command effects log lifetime test

Add a regression test for namespace head command effects log lifetime.

Create a two-path loop subsystem, remove the first controller, and issue
an I/O passthrough command through the namespace-head character device.
Kernels that keep the command effects log pointer in the shared namespace
head report the stale access through KASAN.

Signed-off-by: Yao Sang <[email protected]>
---
 tests/nvme/070     | 57 ++++++++++++++++++++++++++++++++++++++++++++++
 tests/nvme/070.out |  2 ++
 2 files changed, 59 insertions(+)
 create mode 100755 tests/nvme/070
 create mode 100644 tests/nvme/070.out

diff --git a/tests/nvme/070 b/tests/nvme/070
new file mode 100755
index 0000000..39195be
--- /dev/null
+++ b/tests/nvme/070
@@ -0,0 +1,57 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2026 Yao Sang <[email protected]>
+#
+# Test NVMe multipath command effects log lifetime.
+
+. tests/nvme/rc
+
+nvme_trtype=loop
+
+DESCRIPTION="test NVMe multipath command effects log lifetime"
+QUICK=1
+CHECK_DMESG=1
+
+requires() {
+	_nvme_requires
+	_have_loop
+	_have_module_param_value nvme_core multipath Y
+	_require_nvme_trtype_is_loop
+	_have_kernel_options KASAN
+}
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	local first_ctrl
+	local ngdev
+	local ns
+	local nsid
+	local -a ports
+
+	_setup_nvmet
+	_nvmet_target_setup --ports 2
+
+	_get_nvmet_ports "${def_subsysnqn}" ports
+
+	_nvme_connect_subsys --port "${ports[0]}"
+	first_ctrl=$(_find_nvme_dev "${def_subsysnqn}")
+
+	_nvme_connect_subsys --port "${ports[1]}"
+
+	ns=$(_find_nvme_ns "${def_subsys_uuid}")
+	nsid=$(cat "/sys/block/${ns}/nsid")
+	ngdev="${ns/nvme/ng}"
+
+	_nvme_disconnect_ctrl "${first_ctrl}"
+
+	if ! nvme io-passthru "/dev/${ngdev}" --opcode 0 \
+		--namespace-id "${nsid}" >> "${FULL}" 2>&1; then
+		echo "io-passthru failed"
+	fi
+
+	_nvme_disconnect_subsys >> "${FULL}" 2>&1
+	_nvmet_target_cleanup
+
+	echo "Test complete"
+}
diff --git a/tests/nvme/070.out b/tests/nvme/070.out
new file mode 100644
index 0000000..b765a28
--- /dev/null
+++ b/tests/nvme/070.out
@@ -0,0 +1,2 @@
+Running nvme/070
+Test complete
-- 
2.25.1