netfs: zero the tail of a short DIO/unbuffered readgrafted

The buffered read collector zero-fills the tail of a short read that
stops below the inode's i_size (netfs_clear_unread()), so a read that
races an extending write still returns the expected number of bytes.
The non-buffered collector path does no such thing: it just records
how much was transferred.

Add the same zero-fill for the non-buffered case, gated on
NETFS_SREQ_CLEAR_TAIL: a subreq's source sets that flag when a short
result from it is known to be safe to treat as a hole, as opposed to
NETFS_SREQ_HIT_EOF, which means the read genuinely ran off the end of
the file and should be reported short as-is. Only CLEAR_TAIL should
zero-fill here; a real EOF must stay a real short read.

No source currently sets CLEAR_TAIL on an unbuffered/DIO subrequest,
so this is inert on its own -- a following change teaches cifs to set
it in the one case that needs it.

Fixes: e2d46f2ec332 ("netfs: Change the read result collector to only use one work item")
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Paulo Alcantara <pc@manguebit.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Ronnie Sahlberg <ronniesahlberg@gmail.com>
Cc: Shyam Prasad N <sprasad@microsoft.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: Bharath SM <bharathsm@microsoft.com>
Cc: stable@vger.kernel.org

1 files changed, 607 insertions, 0 deletions

diff --git a/drivers/firewire/node-tree-test.c b/drivers/firewire/node-tree-test.c
new file mode 100644
index 000000000..5e6bb5853
--- /dev/null
+++ b/drivers/firewire/node-tree-test.c
@@ -0,0 +1,607 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// node-tree-test.c - An application of Kunit to test node tree.
+//
+// Copyright (c) 2026 Takashi Sakamoto
+//
+// This file can not be built independently since it is intentionally included in core-topology.c.
+
+#include <kunit/test.h>
+#include <kunit/test-bug.h>
+#include <kunit/device.h>
+
+struct private_data {
+	struct fw_card *card;
+	unsigned int release_count;
+};
+
+static int node_tree_test_init(struct kunit *test)
+{
+	struct private_data *data;
+
+	data = kunit_kzalloc(test, sizeof(*data), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, data);
+
+	data->card = kunit_kzalloc(test, sizeof(struct fw_card), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, data->card);
+
+	data->card->device = kunit_device_register(test, "dummy-device");
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, data->card->device);
+
+	test->priv = data;
+
+	return 0;
+}
+
+static void node_tree_test_exit(struct kunit *test)
+{
+	struct private_data *data = test->priv;
+
+	kunit_device_unregister(test, data->card->device);
+	kunit_kfree(test, data->card);
+	kunit_kfree(test, data);
+}
+
+static void release_fw_node(struct fw_card *card, struct fw_node *node, struct fw_node *parent)
+{
+	struct private_data *data = kunit_get_current_test()->priv;
+
+	fw_node_put(node);
+	++data->release_count;
+}
+
+static void node_tree_test_two_nodes(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 1   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==|==++
+	//            |
+	//      +-----+
+	//      |
+	// ++===|==x==x==++
+	// ||  P0 P1 P2  ||
+	// ||    phy 0   ||
+	// ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000080,
+		0x8100005e,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x01;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 1);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 2);
+}
+
+static void node_tree_test_two_nodes_1394a(struct kunit *test)
+{
+	//         root
+	// ++===============++
+	// ||      phy 0    ||
+	// ||  P0 P1 P2 P3  ||
+	// ++===|==|==|==|==++
+	//            |
+	//         +--+
+	//         |
+	// ++===|==|==|==|==|==++
+	// ||  P0 P1 P2 P3 P4  ||
+	// ||       phy 1      ||
+	// ++==================++
+	//
+	// NOTE: Just for Self-ID Packets Zero and One.
+	static const u32 self_id_sequence[] = {
+		0x80000065, 0x80814000,
+		0x8100005d, 0x81810000,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x01;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 4);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+	KUNIT_EXPECT_NULL(test, node->ports[3]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 5);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[1], parent);
+	KUNIT_EXPECT_NULL(test, node->ports[2]);
+	KUNIT_EXPECT_NULL(test, node->ports[3]);
+	KUNIT_EXPECT_NULL(test, node->ports[4]);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 2);
+}
+
+static void node_tree_test_three_nodes_case0(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 2   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==|==++
+	//      |     |
+	//      +--+  +-----------------+
+	//         |                    |
+	// ++===|==|==x==++  ++===|==|==|==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 0   ||  ||    phy 1   ||
+	// ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000060,
+		0x81000058,
+		0x820000dc,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x02;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[0];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[1], parent);
+
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[2], parent);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 3);
+}
+
+static void node_tree_test_three_nodes_case1(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 2   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==x==++
+	//         |
+	//         |  +-----------+
+	//         |  |           |
+	// ++===|==|==|==++  ++===|==x==x==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 1   ||  ||    phy 0   ||
+	// ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000080,
+		0x8100006c,
+		0x82000070,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x02;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[1], parent);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 1);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 3);
+}
+
+static void node_tree_test_four_nodes_case0(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 3   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==|==++
+	//         |
+	//         |  +-----------+  +--------------+
+	//         |  |           |  |              |
+	// ++===|==|==|==++  ++===|==|==x==++  ++===|==x==x==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 2   ||  ||    phy 1   ||  ||    phy 0   ||
+	// ++============++  ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000080,
+		0x810000b0,
+		0x8200006c,
+		0x83000074,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x03);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NULL(test, node->ports[2]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[1], parent);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+
+	parent = node;
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 1);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 4);
+}
+
+static void node_tree_test_four_nodes_case1(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 3   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==x==++
+	//      |
+	//      |  +--------------------------------+
+	//      |  |  +-----------+                 |
+	// ++===|==|==|==++  ++===|==x==x==++  ++===|==|==|==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 2   ||  ||    phy 1   ||  ||    phy 0   ||
+	// ++============++  ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000d0,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x03);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[0];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 1);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NULL(test, node->ports[2]);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 4);
+}
+
+static void node_tree_test_four_nodes_case2(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 3   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==|==++
+	//      |     |
+	//      |     +-----------------------------+
+	//      |  +--------------+                 |
+	// ++===|==|==x==++  ++===|==|==|==++  ++===|==x==x==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 1   ||  ||    phy 0   ||  ||    phy 2   ||
+	// ++============++  ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x810000b0,
+		0x82000080,
+		0x830000dc,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x03);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 1);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+
+	node = parent->ports[0];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+
+	parent = node;
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NULL(test, node->ports[2]);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 4);
+}
+
+static void node_tree_test_four_nodes_case3(struct kunit *test)
+{
+	//       root
+	// ++============++
+	// ||    phy 3   ||
+	// ||  P0 P1 P2  ||
+	// ++===|==|==|==++
+	//      |  |  +--------------------------------+
+	//      |  +--------------------+              |
+	//      |                       |              |
+	// ++===|==|==x==++  ++===|==|==|==++  ++===|==|==x==++
+	// ||  P0 P1 P2  ||  ||  P0 P1 P2  ||  ||  P0 P1 P2  ||
+	// ||    phy 0   ||  ||    phy 1   ||  ||    phy 2   ||
+	// ++============++  ++============++  ++============++
+	//
+	static const u32 self_id_sequence[] = {
+		0x80000090,
+		0x81000058,
+		0x82000060,
+		0x830000fc,
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NOT_NULL(test, card->local_node);
+	KUNIT_EXPECT_PTR_EQ(test, card->local_node, card->root_node);
+
+	struct fw_node *node = card->root_node;
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x03);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_NOT_NULL(test, node->ports[2]);
+
+	struct fw_node *parent = node;
+	node = parent->ports[2];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x02);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[1], parent);
+
+	node = parent->ports[1];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x01);
+	KUNIT_EXPECT_EQ(test, node->port_count, 3);
+	KUNIT_EXPECT_NULL(test, node->ports[0]);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[2], parent);
+
+	node = parent->ports[0];
+	KUNIT_EXPECT_EQ(test, node->node_id, LOCAL_BUS | 0x00);
+	KUNIT_EXPECT_EQ(test, node->port_count, 2);
+	KUNIT_EXPECT_PTR_EQ(test, node->ports[0], parent);
+	KUNIT_EXPECT_NULL(test, node->ports[1]);
+
+	++card->color;
+	for_each_fw_node(card, card->root_node, release_fw_node);
+	KUNIT_EXPECT_EQ(test, data->release_count, 4);
+}
+
+static void node_tree_test_invalid_extended_self_id_sequence(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// content of self ID packet for the phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000d1, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_phy_id(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// phy ID for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x8f0000d0, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_child_port_count(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// count of child ports for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000fc, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static void node_tree_test_invalid_parent_port_count(struct kunit *test)
+{
+	// Use the same node tree as node_tree_test_four_nodes_case1, except for the invalid
+	// count of parent ports for phy 3.
+	static const u32 self_id_sequence[] = {
+		0x80000094,
+		0x81000080,
+		0x820000bc,
+		0x830000e8, // Invalid.
+	};
+	struct private_data *data = test->priv;
+	struct fw_card *card = data->card;
+
+	card->node_id = LOCAL_BUS | 0x03;
+
+	card->local_node = build_tree(card, self_id_sequence, ARRAY_SIZE(self_id_sequence), 123);
+	KUNIT_EXPECT_NULL(test, card->local_node);
+}
+
+static struct kunit_case node_tree_test_cases[] = {
+	KUNIT_CASE(node_tree_test_two_nodes),
+	KUNIT_CASE(node_tree_test_two_nodes_1394a),
+	KUNIT_CASE(node_tree_test_three_nodes_case0),
+	KUNIT_CASE(node_tree_test_three_nodes_case1),
+	KUNIT_CASE(node_tree_test_four_nodes_case0),
+	KUNIT_CASE(node_tree_test_four_nodes_case1),
+	KUNIT_CASE(node_tree_test_four_nodes_case2),
+	KUNIT_CASE(node_tree_test_four_nodes_case3),
+	KUNIT_CASE(node_tree_test_invalid_extended_self_id_sequence),
+	KUNIT_CASE(node_tree_test_invalid_phy_id),
+	KUNIT_CASE(node_tree_test_invalid_child_port_count),
+	KUNIT_CASE(node_tree_test_invalid_parent_port_count),
+	{}
+};
+
+static struct kunit_suite node_tree_test_suite = {
+	.name = "firewire-node-tree",
+	.init = node_tree_test_init,
+	.exit = node_tree_test_exit,
+	.test_cases = node_tree_test_cases,
+};
+kunit_test_suite(node_tree_test_suite);