Create a new blktrace test group and add a regression test for a
blktrace false positive WARNING that occurs when zone management
commands are traced with blktrace on V1 version.

Bug: https://syzkaller.appspot.com/bug?extid=153e64c0aa875d7e4c37
Location: kernel/trace/blktrace.c:367-368

The test:
1. Creates a zoned null_blk device (8 zones, 1GB, no conventional zones)
2. Starts blktrace on the device
3. Issues zone open command for all zones
4. Checks dmesg for the false positive WARNING

Device configuration:
- Total size: 1GB
- Zone size: 128MB
- Number of zones: 8
- Conventional zones: 0

If the WARNING is found, the bug is present and logged to the full
output. If no WARNING appears, the bug is fixed.

Note: The bug uses WARN_ON_ONCE, so it triggers only once per boot.
Subsequent runs after the first trigger will not show the WARNING:
commit 4a0940bdcac260be1e3460e99464fa63d317c6a2
Author: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Date:   Mon Oct 27 19:46:19 2025 -0700

    blktrace: use debug print to report dropped events

https://lore.kernel.org/linux-block/20251028024619.2906-1-ckulkarnilinux@gmail.com/

Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
---
V2->V3:
- Remove _init_null_blk call (not needed with configfs)
- Change nullb0 to nullb1 (works with built-in null_blk)
- Update blktrace to use long options and store in TMPDIR
- Remove debug || true from wait command
- Keep || true from grep -c needed to prevent false failure
- Remove && operators in group_requires()
---
 tests/blktrace/001     | 90 ++++++++++++++++++++++++++++++++++++++++++
 tests/blktrace/001.out |  2 +
 tests/blktrace/rc      | 13 ++++++
 3 files changed, 105 insertions(+)
 create mode 100755 tests/blktrace/001
 create mode 100644 tests/blktrace/001.out
 create mode 100644 tests/blktrace/rc

diff --git a/tests/blktrace/001 b/tests/blktrace/001
new file mode 100755
index 0000000..2cdad02
--- /dev/null
+++ b/tests/blktrace/001
@@ -0,0 +1,90 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2025 Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
+#
+# Regression test for blktrace false positive WARNING on zone management
+# commands.
+#
+# Bug: https://syzkaller.appspot.com/bug?extid=153e64c0aa875d7e4c37
+# Location: kernel/trace/blktrace.c:367-368
+#
+# The bug triggers a WARNING when zone management commands (zone open/close/
+# finish/reset) are traced with blktrace on V1 version. This is a false
+# positive that should be fixed.
+
+. tests/blktrace/rc
+. common/null_blk
+
+DESCRIPTION="blktrace zone management command tracing"
+QUICK=1
+
+requires() {
+	_have_program blkzone
+	_have_null_blk
+	_have_module_param null_blk zoned
+}
+
+test() {
+	echo "Running ${TEST_NAME}"
+
+	local blktrace_pid
+	local warning_count
+	local device
+
+	# Create zoned null_blk device via configfs
+	# 8 zones, 1GB total, 128MB per zone, no conventional zones
+	if ! _configure_null_blk nullb1 \
+		memory_backed=1 \
+		zone_size=128 \
+		zone_nr_conv=0 \
+		size=1024 \
+		zoned=1 \
+		power=1; then
+		return 1
+	fi
+
+	device=/dev/nullb1
+
+	# Verify it's a zoned device
+	local zoned_mode
+	zoned_mode=$(cat /sys/block/nullb1/queue/zoned)
+	if [[ "$zoned_mode" != "host-managed" ]]; then
+		echo "Device is not zoned (mode: $zoned_mode)"
+		_exit_null_blk
+		return 1
+	fi
+
+	# Start blktrace
+	blktrace --dev="${device}" --output=trace --output-dir="$TMPDIR" \
+		>> "$FULL" 2>&1 &
+	blktrace_pid=$!
+	sleep 2
+
+	# Verify blktrace started
+	if ! ps -p $blktrace_pid > /dev/null 2>&1; then
+		echo "blktrace failed to start"
+		_exit_null_blk
+		return 1
+	fi
+
+	# Issue zone open command for all zones (triggers bug if present)
+	blkzone open "${device}" >> "$FULL" 2>&1
+
+	sleep 1
+
+	# Stop blktrace
+	kill $blktrace_pid 2>/dev/null
+	wait $blktrace_pid 2>/dev/null
+
+	# Check for WARNING (bug present if WARNING found)
+	warning_count=$(_dmesg_since_test_start | grep -c "WARNING.*blktrace.c:367" || true)
+
+	if [[ $warning_count -gt 0 ]]; then
+		echo "WARNING: blktrace bug detected at blktrace.c:367"
+		_dmesg_since_test_start | grep -A 10 "WARNING.*blktrace.c:367" >> "$FULL"
+	fi
+
+	_exit_null_blk
+
+	echo "Test complete"
+}
diff --git a/tests/blktrace/001.out b/tests/blktrace/001.out
new file mode 100644
index 0000000..a122a65
--- /dev/null
+++ b/tests/blktrace/001.out
@@ -0,0 +1,2 @@
+Running blktrace/001
+Test complete
diff --git a/tests/blktrace/rc b/tests/blktrace/rc
new file mode 100644
index 0000000..04c599f
--- /dev/null
+++ b/tests/blktrace/rc
@@ -0,0 +1,13 @@
+#!/bin/bash
+# SPDX-License-Identifier: GPL-3.0+
+# Copyright (C) 2025 Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
+#
+# Tests for blktrace infrastructure
+
+. common/rc
+
+group_requires() {
+	_have_root
+	_have_blktrace
+	_have_program blkparse
+}
-- 
2.40.0