x86/kprobes: Fix crash when probing CS CALL instructionsgrafted

When using eBPF to probe CS CALL instructions within a function,
a crash can be triggered.

The eBPF tool probes offset 257 of the __hrtimer_run_queues()
function:

<__hrtimer_run_queues+249>:  nopl   0x0(%rax,%rax,1)
<__hrtimer_run_queues+254>:  mov    %r14,%rdi
<__hrtimer_run_queues+257>:  cs call <__x86_indirect_thunk_r12>
<__hrtimer_run_queues+263>:  mov    %eax,%r12d
<__hrtimer_run_queues+266>:  xchg   %ax,%ax
<__hrtimer_run_queues+268>:  mov    %r13,%rdi

Which triggers this crash:

  BUG: unable to handle page fault for address: 00000000000f41c9
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 0 P4D 0
  Oops: 0002 [#1] SMP NOPTI
  CPU: 1 PID: 0 Comm: swapper/1 Kdump: loaded Tainted: P
  RIP: 0010:__hrtimer_run_queues+0x106/0x230

Note that __hrtimer_run_queues+0x106 is __hrtimer_run_queues+262, which is
at the 6th byte of the above CS CALL instruction. Since the CS CALL
instruction occupies 6 bytes, the exception occurred in the middle of that
call instruction.

The root cause is that when using eBPF tools to probe in the middle of a
function, a kprobe with INT3 is used as the underlying implementation.

During single-step emulation of the original CALL instruction,
int3_emulate_call() assumes that the probed CALL instruction is 5 bytes
long. However, the actual CS-prefixed CALL instruction occupies 6 bytes,
so it constructs an incorrect exception return address. When the CPU
returns from the kprobe handler, the next instruction to be executed is at
the address of the last byte of that CS CALL instruction. Coincidentally,
starting from that address, the CPU fetches and decodes a completely
different instruction, which ultimately triggers a kernel crash.

Fix the issue by using the actual instruction length obtained from
the instruction decoder when constructing the exception return
address, rather than relying on the hardcoded CALL_INSN_SIZE macro.

[ mingo: Refined the changelog ]

Fixes: 6256e668b7af ("x86/kprobes: Use int3 instead of debug trap for single-step")
Suggested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Jinke Han <jinkehan@didiglobal.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Borislav Petkov <bp@alien8.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20260908073742.GA10517@didi-ThinkCentre-M920t-N000

1 files changed, 917 insertions, 0 deletions

diff --git a/drivers/firewire/packet-serdes-test.c b/drivers/firewire/packet-serdes-test.c
new file mode 100644
index 000000000..62ba43375
--- /dev/null
+++ b/drivers/firewire/packet-serdes-test.c
@@ -0,0 +1,917 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+//
+// packet-serdes-test.c - An application of Kunit to check serialization/deserialization of packets
+//			  defined by IEEE 1394.
+//
+// Copyright (c) 2024 Takashi Sakamoto
+
+#include <kunit/test.h>
+
+#include <linux/firewire-constants.h>
+
+#include "packet-header-definitions.h"
+#include "phy-packet-definitions.h"
+
+static void serialize_async_header_common(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					  unsigned int dst_id, unsigned int tlabel,
+					  unsigned int retry, unsigned int tcode,
+					  unsigned int priority, unsigned int src_id)
+{
+	async_header_set_destination(header, dst_id);
+	async_header_set_tlabel(header, tlabel);
+	async_header_set_retry(header, retry);
+	async_header_set_tcode(header, tcode);
+	async_header_set_priority(header, priority);
+	async_header_set_source(header, src_id);
+}
+
+static void serialize_async_header_request(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					   unsigned int dst_id, unsigned int tlabel,
+					   unsigned int retry, unsigned int tcode,
+					   unsigned int priority, unsigned int src_id, u64 offset)
+{
+	serialize_async_header_common(header, dst_id, tlabel, retry, tcode, priority, src_id);
+	async_header_set_offset(header, offset);
+}
+
+static void serialize_async_header_quadlet_request(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						   unsigned int dst_id, unsigned int tlabel,
+						   unsigned int retry, unsigned int tcode,
+						   unsigned int priority, unsigned int src_id,
+						   u64 offset)
+{
+	serialize_async_header_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+				       offset);
+}
+
+static void serialize_async_header_block_request(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						 unsigned int dst_id, unsigned int tlabel,
+						 unsigned int retry, unsigned int tcode,
+						 unsigned int priority, unsigned int src_id,
+						 u64 offset, unsigned int data_length,
+						 unsigned int extended_tcode)
+{
+	serialize_async_header_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+				       offset);
+	async_header_set_data_length(header, data_length);
+	async_header_set_extended_tcode(header, extended_tcode);
+}
+
+static void serialize_async_header_response(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					    unsigned int dst_id, unsigned int tlabel,
+					    unsigned int retry, unsigned int tcode,
+					    unsigned int priority, unsigned int src_id,
+					    unsigned int rcode)
+{
+	serialize_async_header_common(header, dst_id, tlabel, retry, tcode, priority, src_id);
+	async_header_set_rcode(header, rcode);
+}
+
+static void serialize_async_header_quadlet_response(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						    unsigned int dst_id, unsigned int tlabel,
+						    unsigned int retry, unsigned int tcode,
+						    unsigned int priority, unsigned int src_id,
+						    unsigned int rcode)
+{
+	serialize_async_header_response(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					rcode);
+}
+
+static void serialize_async_header_block_response(u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						  unsigned int dst_id, unsigned int tlabel,
+						  unsigned int retry, unsigned int tcode,
+						  unsigned int priority, unsigned int src_id,
+						  unsigned int rcode, unsigned int data_length,
+						  unsigned int extended_tcode)
+{
+	serialize_async_header_response(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					rcode);
+	async_header_set_data_length(header, data_length);
+	async_header_set_extended_tcode(header, extended_tcode);
+}
+
+static void deserialize_async_header_common(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					    unsigned int *dst_id, unsigned int *tlabel,
+					    unsigned int *retry, unsigned int *tcode,
+					    unsigned int *priority, unsigned int *src_id)
+{
+	*dst_id = async_header_get_destination(header);
+	*tlabel = async_header_get_tlabel(header);
+	*retry = async_header_get_retry(header);
+	*tcode = async_header_get_tcode(header);
+	*priority = async_header_get_priority(header);
+	*src_id = async_header_get_source(header);
+}
+
+static void deserialize_async_header_request(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					     unsigned int *dst_id, unsigned int *tlabel,
+					     unsigned int *retry, unsigned int *tcode,
+					     unsigned int *priority, unsigned int *src_id,
+					     u64 *offset)
+{
+	deserialize_async_header_common(header, dst_id, tlabel, retry, tcode, priority, src_id);
+	*offset = async_header_get_offset(header);
+}
+
+static void deserialize_async_header_quadlet_request(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						     unsigned int *dst_id, unsigned int *tlabel,
+						     unsigned int *retry, unsigned int *tcode,
+						     unsigned int *priority, unsigned int *src_id,
+						     u64 *offset)
+{
+	deserialize_async_header_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					 offset);
+}
+
+static void deserialize_async_header_block_request(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						   unsigned int *dst_id, unsigned int *tlabel,
+						   unsigned int *retry, unsigned int *tcode,
+						   unsigned int *priority, unsigned int *src_id,
+						   u64 *offset,
+						   unsigned int *data_length,
+						   unsigned int *extended_tcode)
+{
+	deserialize_async_header_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					 offset);
+	*data_length = async_header_get_data_length(header);
+	*extended_tcode = async_header_get_extended_tcode(header);
+}
+
+static void deserialize_async_header_response(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+					      unsigned int *dst_id, unsigned int *tlabel,
+					      unsigned int *retry, unsigned int *tcode,
+					      unsigned int *priority, unsigned int *src_id,
+					      unsigned int *rcode)
+{
+	deserialize_async_header_common(header, dst_id, tlabel, retry, tcode, priority, src_id);
+	*rcode = async_header_get_rcode(header);
+}
+
+static void deserialize_async_header_quadlet_response(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						      unsigned int *dst_id, unsigned int *tlabel,
+						      unsigned int *retry, unsigned int *tcode,
+						      unsigned int *priority, unsigned int *src_id,
+						      unsigned int *rcode)
+{
+	deserialize_async_header_response(header, dst_id, tlabel, retry, tcode, priority, src_id, rcode);
+}
+
+static void deserialize_async_header_block_response(const u32 header[ASYNC_HEADER_QUADLET_COUNT],
+						    unsigned int *dst_id, unsigned int *tlabel,
+						    unsigned int *retry, unsigned int *tcode,
+						    unsigned int *priority, unsigned int *src_id,
+						    unsigned int *rcode, unsigned int *data_length,
+						    unsigned int *extended_tcode)
+{
+	deserialize_async_header_response(header, dst_id, tlabel, retry, tcode, priority, src_id, rcode);
+	*data_length = async_header_get_data_length(header);
+	*extended_tcode = async_header_get_extended_tcode(header);
+}
+
+static void serialize_isoc_header(u32 *header, unsigned int data_length, unsigned int tag,
+				  unsigned int channel, unsigned int tcode, unsigned int sy)
+{
+	isoc_header_set_data_length(header, data_length);
+	isoc_header_set_tag(header, tag);
+	isoc_header_set_channel(header, channel);
+	isoc_header_set_tcode(header, tcode);
+	isoc_header_set_sy(header, sy);
+}
+
+static void deserialize_isoc_header(u32 header, unsigned int *data_length, unsigned int *tag,
+				    unsigned int *channel, unsigned int *tcode, unsigned int *sy)
+{
+	*data_length = isoc_header_get_data_length(header);
+	*tag = isoc_header_get_tag(header);
+	*channel = isoc_header_get_channel(header);
+	*tcode = isoc_header_get_tcode(header);
+	*sy = isoc_header_get_sy(header);
+}
+
+static void serialize_phy_packet_self_id_zero(u32 *quadlet, unsigned int packet_identifier,
+					      unsigned int phy_id, bool extended,
+					      bool link_is_active, unsigned int gap_count,
+					      unsigned int scode, bool is_contender,
+					      unsigned int power_class, bool is_initiated_reset,
+					      bool has_more_packets)
+{
+	phy_packet_set_packet_identifier(quadlet, packet_identifier);
+	phy_packet_self_id_set_phy_id(quadlet, phy_id);
+	phy_packet_self_id_set_extended(quadlet, extended);
+	phy_packet_self_id_zero_set_link_active(quadlet, link_is_active);
+	phy_packet_self_id_zero_set_gap_count(quadlet, gap_count);
+	phy_packet_self_id_zero_set_scode(quadlet, scode);
+	phy_packet_self_id_zero_set_contender(quadlet, is_contender);
+	phy_packet_self_id_zero_set_power_class(quadlet, power_class);
+	phy_packet_self_id_zero_set_initiated_reset(quadlet, is_initiated_reset);
+	phy_packet_self_id_set_more_packets(quadlet, has_more_packets);
+}
+
+static void deserialize_phy_packet_self_id_zero(u32 quadlet, unsigned int *packet_identifier,
+						unsigned int *phy_id, bool *extended,
+						bool *link_is_active, unsigned int *gap_count,
+						unsigned int *scode, bool *is_contender,
+						unsigned int *power_class,
+						bool *is_initiated_reset, bool *has_more_packets)
+{
+	*packet_identifier = phy_packet_get_packet_identifier(quadlet);
+	*phy_id = phy_packet_self_id_get_phy_id(quadlet);
+	*extended = phy_packet_self_id_get_extended(quadlet);
+	*link_is_active = phy_packet_self_id_zero_get_link_active(quadlet);
+	*gap_count = phy_packet_self_id_zero_get_gap_count(quadlet);
+	*scode = phy_packet_self_id_zero_get_scode(quadlet);
+	*is_contender = phy_packet_self_id_zero_get_contender(quadlet);
+	*power_class = phy_packet_self_id_zero_get_power_class(quadlet);
+	*is_initiated_reset = phy_packet_self_id_zero_get_initiated_reset(quadlet);
+	*has_more_packets = phy_packet_self_id_get_more_packets(quadlet);
+}
+
+static void serialize_phy_packet_self_id_extended(u32 *quadlet, unsigned int packet_identifier,
+						  unsigned int phy_id, bool extended,
+						  unsigned int sequence, bool has_more_packets)
+{
+	phy_packet_set_packet_identifier(quadlet, packet_identifier);
+	phy_packet_self_id_set_phy_id(quadlet, phy_id);
+	phy_packet_self_id_set_extended(quadlet, extended);
+	phy_packet_self_id_extended_set_sequence(quadlet, sequence);
+	phy_packet_self_id_set_more_packets(quadlet, has_more_packets);
+}
+
+static void deserialize_phy_packet_self_id_extended(u32 quadlet, unsigned int *packet_identifier,
+						    unsigned int *phy_id, bool *extended,
+						    unsigned int *sequence, bool *has_more_packets)
+{
+	*packet_identifier = phy_packet_get_packet_identifier(quadlet);
+	*phy_id = phy_packet_self_id_get_phy_id(quadlet);
+	*extended = phy_packet_self_id_get_extended(quadlet);
+	*sequence = phy_packet_self_id_extended_get_sequence(quadlet);
+	*has_more_packets = phy_packet_self_id_get_more_packets(quadlet);
+}
+
+static void serialize_phy_packet_phy_config(u32 *quadlet, unsigned int packet_identifier,
+					    unsigned int root_id, bool has_force_root_node,
+					    bool has_gap_count_optimization, unsigned int gap_count)
+{
+	phy_packet_set_packet_identifier(quadlet, packet_identifier);
+	phy_packet_phy_config_set_root_id(quadlet, root_id);
+	phy_packet_phy_config_set_force_root_node(quadlet, has_force_root_node);
+	phy_packet_phy_config_set_gap_count_optimization(quadlet, has_gap_count_optimization);
+	phy_packet_phy_config_set_gap_count(quadlet, gap_count);
+}
+
+static void deserialize_phy_packet_phy_config(u32 quadlet, unsigned int *packet_identifier,
+					      unsigned int *root_id, bool *has_force_root_node,
+					      bool *has_gap_count_optimization,
+					      unsigned int *gap_count)
+{
+	*packet_identifier = phy_packet_get_packet_identifier(quadlet);
+	*root_id = phy_packet_phy_config_get_root_id(quadlet);
+	*has_force_root_node = phy_packet_phy_config_get_force_root_node(quadlet);
+	*has_gap_count_optimization = phy_packet_phy_config_get_gap_count_optimization(quadlet);
+	*gap_count = phy_packet_phy_config_get_gap_count(quadlet);
+}
+
+static void test_async_header_write_quadlet_request(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc05100,
+		0xffc1ffff,
+		0xf0000234,
+		0x1f0000c0,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	u64 offset;
+	u32 quadlet_data;
+
+	deserialize_async_header_quadlet_request(expected, &dst_id, &tlabel, &retry, &tcode,
+						 &priority, &src_id, &offset);
+	quadlet_data = async_header_get_quadlet_data(expected);
+
+	KUNIT_EXPECT_EQ(test, 0xffc0, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x14, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_WRITE_QUADLET_REQUEST, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc1, src_id);
+	KUNIT_EXPECT_EQ(test, 0xfffff0000234, offset);
+	KUNIT_EXPECT_EQ(test, 0x1f0000c0, quadlet_data);
+
+	serialize_async_header_quadlet_request(header, dst_id, tlabel, retry, tcode, priority,
+					       src_id, offset);
+	async_header_set_quadlet_data(header, quadlet_data);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_write_block_request(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc06510,
+		0xffc1ecc0,
+		0x00000000,
+		0x00180000,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	u64 offset;
+	unsigned int data_length;
+	unsigned int extended_tcode;
+
+	deserialize_async_header_block_request(expected, &dst_id, &tlabel, &retry, &tcode,
+					       &priority, &src_id, &offset, &data_length,
+					       &extended_tcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc0, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x19, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_WRITE_BLOCK_REQUEST, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc1, src_id);
+	KUNIT_EXPECT_EQ(test, 0xecc000000000, offset);
+	KUNIT_EXPECT_EQ(test, 0x0018, data_length);
+	KUNIT_EXPECT_EQ(test, 0x0000, extended_tcode);
+
+	serialize_async_header_block_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					     offset, data_length, extended_tcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_write_response(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc15120,
+		0xffc00000,
+		0x00000000,
+		0x00000000,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	unsigned int rcode;
+
+	deserialize_async_header_quadlet_response(expected, &dst_id, &tlabel, &retry, &tcode,
+						  &priority, &src_id, &rcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc1, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x14, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_WRITE_RESPONSE, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc0, src_id);
+	KUNIT_EXPECT_EQ(test, RCODE_COMPLETE, rcode);
+
+	serialize_async_header_quadlet_response(header, dst_id, tlabel, retry, tcode, priority,
+						src_id, rcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected) - sizeof(expected[0]));
+}
+
+static void test_async_header_read_quadlet_request(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc0f140,
+		0xffc1ffff,
+		0xf0000984,
+		0x00000000,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	u64 offset;
+
+	deserialize_async_header_quadlet_request(expected, &dst_id, &tlabel, &retry, &tcode,
+						 &priority, &src_id, &offset);
+
+	KUNIT_EXPECT_EQ(test, 0xffc0, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x3c, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_READ_QUADLET_REQUEST, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc1, src_id);
+	KUNIT_EXPECT_EQ(test, 0xfffff0000984, offset);
+
+	serialize_async_header_quadlet_request(header, dst_id, tlabel, retry, tcode, priority,
+					       src_id, offset);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_read_quadlet_response(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc1f160,
+		0xffc00000,
+		0x00000000,
+		0x00000180,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	unsigned int rcode;
+	u32 quadlet_data;
+
+	deserialize_async_header_quadlet_response(expected, &dst_id, &tlabel, &retry, &tcode,
+						  &priority, &src_id, &rcode);
+	quadlet_data = async_header_get_quadlet_data(expected);
+
+	KUNIT_EXPECT_EQ(test, 0xffc1, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x3c, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_READ_QUADLET_RESPONSE, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc0, src_id);
+	KUNIT_EXPECT_EQ(test, RCODE_COMPLETE, rcode);
+	KUNIT_EXPECT_EQ(test, 0x00000180, quadlet_data);
+
+	serialize_async_header_quadlet_response(header, dst_id, tlabel, retry, tcode, priority,
+						src_id, rcode);
+	async_header_set_quadlet_data(header, quadlet_data);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_read_block_request(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc0e150,
+		0xffc1ffff,
+		0xf0000400,
+		0x00200000,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	u64 offset;
+	unsigned int data_length;
+	unsigned int extended_tcode;
+
+	deserialize_async_header_block_request(expected, &dst_id, &tlabel, &retry, &tcode,
+					       &priority, &src_id, &offset, &data_length,
+					       &extended_tcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc0, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x38, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_READ_BLOCK_REQUEST, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc1, src_id);
+	KUNIT_EXPECT_EQ(test, 0xfffff0000400, offset);
+	KUNIT_EXPECT_EQ(test, 0x0020, data_length);
+	KUNIT_EXPECT_EQ(test, 0x0000, extended_tcode);
+
+	serialize_async_header_block_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					     offset, data_length, extended_tcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_read_block_response(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc1e170,
+		0xffc00000,
+		0x00000000,
+		0x00200000,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	unsigned int rcode;
+	unsigned int data_length;
+	unsigned int extended_tcode;
+
+	deserialize_async_header_block_response(expected, &dst_id, &tlabel, &retry, &tcode,
+						&priority, &src_id, &rcode, &data_length,
+						&extended_tcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc1, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x38, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_READ_BLOCK_RESPONSE, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc0, src_id);
+	KUNIT_EXPECT_EQ(test, RCODE_COMPLETE, rcode);
+	KUNIT_EXPECT_EQ(test, 0x0020, data_length);
+	KUNIT_EXPECT_EQ(test, 0x0000, extended_tcode);
+
+	serialize_async_header_block_response(header, dst_id, tlabel, retry, tcode, priority,
+					      src_id, rcode, data_length, extended_tcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_lock_request(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc02d90,
+		0xffc1ffff,
+		0xf0000984,
+		0x00080002,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	u64 offset;
+	unsigned int data_length;
+	unsigned int extended_tcode;
+
+	deserialize_async_header_block_request(expected, &dst_id, &tlabel, &retry, &tcode,
+					       &priority, &src_id, &offset, &data_length,
+					       &extended_tcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc0, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x0b, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_LOCK_REQUEST, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc1, src_id);
+	KUNIT_EXPECT_EQ(test, 0xfffff0000984, offset);
+	KUNIT_EXPECT_EQ(test, 0x0008, data_length);
+	KUNIT_EXPECT_EQ(test, EXTCODE_COMPARE_SWAP, extended_tcode);
+
+	serialize_async_header_block_request(header, dst_id, tlabel, retry, tcode, priority, src_id,
+					     offset, data_length, extended_tcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_async_header_lock_response(struct kunit *test)
+{
+	static const u32 expected[ASYNC_HEADER_QUADLET_COUNT] = {
+		0xffc12db0,
+		0xffc00000,
+		0x00000000,
+		0x00040002,
+	};
+	u32 header[ASYNC_HEADER_QUADLET_COUNT] = {0, 0, 0, 0};
+
+	unsigned int dst_id;
+	unsigned int tlabel;
+	unsigned int retry;
+	unsigned int tcode;
+	unsigned int priority;
+	unsigned int src_id;
+	unsigned int rcode;
+	unsigned int data_length;
+	unsigned int extended_tcode;
+
+	deserialize_async_header_block_response(expected, &dst_id, &tlabel, &retry, &tcode,
+						&priority, &src_id, &rcode, &data_length,
+						&extended_tcode);
+
+	KUNIT_EXPECT_EQ(test, 0xffc1, dst_id);
+	KUNIT_EXPECT_EQ(test, 0x0b, tlabel);
+	KUNIT_EXPECT_EQ(test, 0x01, retry);
+	KUNIT_EXPECT_EQ(test, TCODE_LOCK_RESPONSE, tcode);
+	KUNIT_EXPECT_EQ(test, 0x00, priority);
+	KUNIT_EXPECT_EQ(test, 0xffc0, src_id);
+	KUNIT_EXPECT_EQ(test, RCODE_COMPLETE, rcode);
+	KUNIT_EXPECT_EQ(test, 0x0004, data_length);
+	KUNIT_EXPECT_EQ(test, EXTCODE_COMPARE_SWAP, extended_tcode);
+
+	serialize_async_header_block_response(header, dst_id, tlabel, retry, tcode, priority,
+					      src_id, rcode, data_length, extended_tcode);
+
+	KUNIT_EXPECT_MEMEQ(test, header, expected, sizeof(expected));
+}
+
+static void test_isoc_header(struct kunit *test)
+{
+	const u32 expected = 0x00d08dec;
+	u32 header = 0;
+
+	unsigned int data_length;
+	unsigned int tag;
+	unsigned int channel;
+	unsigned int tcode;
+	unsigned int sy;
+
+	deserialize_isoc_header(expected, &data_length, &tag, &channel, &tcode, &sy);
+
+	KUNIT_EXPECT_EQ(test, 0xd0, data_length);
+	KUNIT_EXPECT_EQ(test, 0x02, tag);
+	KUNIT_EXPECT_EQ(test, 0x0d, channel);
+	KUNIT_EXPECT_EQ(test, 0x0e, tcode);
+	KUNIT_EXPECT_EQ(test, 0x0c, sy);
+
+	serialize_isoc_header(&header, data_length, tag, channel, tcode, sy);
+
+	KUNIT_EXPECT_EQ(test, header, expected);
+}
+
+static void test_phy_packet_self_id_zero_case0(struct kunit *test)
+{
+	// TSB41AB1/2 with 1 port.
+	const u32 expected[] = {0x80458c80};
+	u32 quadlets[] = {0};
+
+	unsigned int packet_identifier;
+	unsigned int phy_id;
+	bool extended;
+	bool link_is_active;
+	unsigned int gap_count;
+	unsigned int scode;
+	bool is_contender;
+	unsigned int power_class;
+	enum phy_packet_self_id_port_status port_status[3];
+	bool is_initiated_reset;
+	bool has_more_packets;
+	unsigned int port_index;
+
+	deserialize_phy_packet_self_id_zero(expected[0], &packet_identifier, &phy_id, &extended,
+					    &link_is_active, &gap_count, &scode, &is_contender,
+					    &power_class, &is_initiated_reset, &has_more_packets);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_SELF_ID, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 0, phy_id);
+	KUNIT_EXPECT_FALSE(test, extended);
+	KUNIT_EXPECT_TRUE(test, link_is_active);
+	KUNIT_EXPECT_EQ(test, 0x05, gap_count);
+	KUNIT_EXPECT_EQ(test, SCODE_400, scode);
+	KUNIT_EXPECT_TRUE(test, is_contender);
+	KUNIT_EXPECT_EQ(test, 0x4, power_class);
+	KUNIT_EXPECT_FALSE(test, is_initiated_reset);
+	KUNIT_EXPECT_FALSE(test, has_more_packets);
+
+	serialize_phy_packet_self_id_zero(quadlets, packet_identifier, phy_id, extended,
+					  link_is_active, gap_count, scode, is_contender,
+					  power_class, is_initiated_reset, has_more_packets);
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		port_status[port_index] =
+			self_id_sequence_get_port_status(expected, ARRAY_SIZE(expected), port_index);
+	}
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_PARENT, port_status[0]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[1]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[2]);
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		self_id_sequence_set_port_status(quadlets, ARRAY_SIZE(quadlets), port_index,
+						 port_status[port_index]);
+	}
+
+	KUNIT_EXPECT_MEMEQ(test, quadlets, expected, sizeof(expected));
+}
+
+static void test_phy_packet_self_id_zero_case1(struct kunit *test)
+{
+	// XIO2213 and TSB81BA3E with 3 ports.
+	const u32 expected[] = {0x817fcc5e};
+	u32 quadlets[] = {0};
+
+	unsigned int packet_identifier;
+	unsigned int phy_id;
+	bool extended;
+	bool link_is_active;
+	unsigned int gap_count;
+	unsigned int scode;
+	bool is_contender;
+	unsigned int power_class;
+	enum phy_packet_self_id_port_status port_status[3];
+	bool is_initiated_reset;
+	bool has_more_packets;
+	unsigned int port_index;
+
+	deserialize_phy_packet_self_id_zero(expected[0], &packet_identifier, &phy_id, &extended,
+					    &link_is_active, &gap_count, &scode, &is_contender,
+					    &power_class, &is_initiated_reset, &has_more_packets);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_SELF_ID, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 1, phy_id);
+	KUNIT_EXPECT_FALSE(test, extended);
+	KUNIT_EXPECT_TRUE(test, link_is_active);
+	KUNIT_EXPECT_EQ(test, 0x3f, gap_count);
+	KUNIT_EXPECT_EQ(test, SCODE_800, scode);
+	KUNIT_EXPECT_TRUE(test, is_contender);
+	KUNIT_EXPECT_EQ(test, 0x4, power_class);
+	KUNIT_EXPECT_TRUE(test, is_initiated_reset);
+	KUNIT_EXPECT_FALSE(test, has_more_packets);
+
+	serialize_phy_packet_self_id_zero(quadlets, packet_identifier, phy_id, extended,
+					  link_is_active, gap_count, scode, is_contender,
+					  power_class, is_initiated_reset, has_more_packets);
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		port_status[port_index] =
+			self_id_sequence_get_port_status(expected, ARRAY_SIZE(expected), port_index);
+	}
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[0]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[1]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_CHILD, port_status[2]);
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		self_id_sequence_set_port_status(quadlets, ARRAY_SIZE(quadlets), port_index,
+						 port_status[port_index]);
+	}
+
+	KUNIT_EXPECT_MEMEQ(test, quadlets, expected, sizeof(expected));
+}
+
+static void test_phy_packet_self_id_zero_and_one(struct kunit *test)
+{
+	// TSB41LV06A with 6 ports.
+	const u32 expected[] = {
+		0x803f8459,
+		0x80815000,
+	};
+	u32 quadlets[] = {0, 0};
+
+	unsigned int packet_identifier;
+	unsigned int phy_id;
+	bool extended;
+	bool link_is_active;
+	unsigned int gap_count;
+	unsigned int scode;
+	bool is_contender;
+	unsigned int power_class;
+	enum phy_packet_self_id_port_status port_status[11];
+	bool is_initiated_reset;
+	bool has_more_packets;
+
+	unsigned int sequence;
+	unsigned int port_index;
+
+	deserialize_phy_packet_self_id_zero(expected[0], &packet_identifier, &phy_id, &extended,
+					    &link_is_active, &gap_count, &scode, &is_contender,
+					    &power_class, &is_initiated_reset, &has_more_packets);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_SELF_ID, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 0, phy_id);
+	KUNIT_EXPECT_FALSE(test, extended);
+	KUNIT_EXPECT_FALSE(test, link_is_active);
+	KUNIT_EXPECT_EQ(test, 0x3f, gap_count);
+	KUNIT_EXPECT_EQ(test, SCODE_400, scode);
+	KUNIT_EXPECT_FALSE(test, is_contender);
+	KUNIT_EXPECT_EQ(test, 0x4, power_class);
+	KUNIT_EXPECT_FALSE(test, is_initiated_reset);
+	KUNIT_EXPECT_TRUE(test, has_more_packets);
+
+	serialize_phy_packet_self_id_zero(quadlets, packet_identifier, phy_id, extended,
+					  link_is_active, gap_count, scode, is_contender,
+					  power_class, is_initiated_reset, has_more_packets);
+
+	deserialize_phy_packet_self_id_extended(expected[1], &packet_identifier, &phy_id, &extended,
+						&sequence, &has_more_packets);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_SELF_ID, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 0, phy_id);
+	KUNIT_EXPECT_TRUE(test, extended);
+	KUNIT_EXPECT_EQ(test, 0, sequence);
+	KUNIT_EXPECT_FALSE(test, has_more_packets);
+
+	serialize_phy_packet_self_id_extended(&quadlets[1], packet_identifier, phy_id, extended,
+					      sequence, has_more_packets);
+
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		port_status[port_index] =
+			self_id_sequence_get_port_status(expected, ARRAY_SIZE(expected), port_index);
+	}
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[0]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[1]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_PARENT, port_status[2]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[3]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[4]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NCONN, port_status[5]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[6]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[7]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[8]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[9]);
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_SELF_ID_PORT_STATUS_NONE, port_status[10]);
+
+	for (port_index = 0; port_index < ARRAY_SIZE(port_status); ++port_index) {
+		self_id_sequence_set_port_status(quadlets, ARRAY_SIZE(quadlets), port_index,
+						 port_status[port_index]);
+	}
+
+	KUNIT_EXPECT_MEMEQ(test, quadlets, expected, sizeof(expected));
+}
+
+static void test_phy_packet_phy_config_force_root_node(struct kunit *test)
+{
+	const u32 expected = 0x02800000;
+	u32 quadlet = 0;
+
+	unsigned int packet_identifier;
+	unsigned int root_id;
+	bool has_force_root_node;
+	bool has_gap_count_optimization;
+	unsigned int gap_count;
+
+	deserialize_phy_packet_phy_config(expected, &packet_identifier, &root_id,
+					  &has_force_root_node, &has_gap_count_optimization,
+					  &gap_count);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_PHY_CONFIG, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 0x02, root_id);
+	KUNIT_EXPECT_TRUE(test, has_force_root_node);
+	KUNIT_EXPECT_FALSE(test, has_gap_count_optimization);
+	KUNIT_EXPECT_EQ(test, 0, gap_count);
+
+	serialize_phy_packet_phy_config(&quadlet, packet_identifier, root_id, has_force_root_node,
+					has_gap_count_optimization, gap_count);
+
+	KUNIT_EXPECT_EQ(test, quadlet, expected);
+}
+
+static void test_phy_packet_phy_config_gap_count_optimization(struct kunit *test)
+{
+	const u32 expected = 0x034f0000;
+	u32 quadlet = 0;
+
+	unsigned int packet_identifier;
+	unsigned int root_id;
+	bool has_force_root_node;
+	bool has_gap_count_optimization;
+	unsigned int gap_count;
+
+	deserialize_phy_packet_phy_config(expected, &packet_identifier, &root_id,
+					  &has_force_root_node, &has_gap_count_optimization,
+					  &gap_count);
+
+	KUNIT_EXPECT_EQ(test, PHY_PACKET_PACKET_IDENTIFIER_PHY_CONFIG, packet_identifier);
+	KUNIT_EXPECT_EQ(test, 0x03, root_id);
+	KUNIT_EXPECT_FALSE(test, has_force_root_node);
+	KUNIT_EXPECT_TRUE(test, has_gap_count_optimization);
+	KUNIT_EXPECT_EQ(test, 0x0f, gap_count);
+
+	serialize_phy_packet_phy_config(&quadlet, packet_identifier, root_id, has_force_root_node,
+					has_gap_count_optimization, gap_count);
+
+	KUNIT_EXPECT_EQ(test, quadlet, expected);
+}
+
+static struct kunit_case packet_serdes_test_cases[] = {
+	KUNIT_CASE(test_async_header_write_quadlet_request),
+	KUNIT_CASE(test_async_header_write_block_request),
+	KUNIT_CASE(test_async_header_write_response),
+	KUNIT_CASE(test_async_header_read_quadlet_request),
+	KUNIT_CASE(test_async_header_read_quadlet_response),
+	KUNIT_CASE(test_async_header_read_block_request),
+	KUNIT_CASE(test_async_header_read_block_response),
+	KUNIT_CASE(test_async_header_lock_request),
+	KUNIT_CASE(test_async_header_lock_response),
+	KUNIT_CASE(test_isoc_header),
+	KUNIT_CASE(test_phy_packet_self_id_zero_case0),
+	KUNIT_CASE(test_phy_packet_self_id_zero_case1),
+	KUNIT_CASE(test_phy_packet_self_id_zero_and_one),
+	KUNIT_CASE(test_phy_packet_phy_config_force_root_node),
+	KUNIT_CASE(test_phy_packet_phy_config_gap_count_optimization),
+	{}
+};
+
+static struct kunit_suite packet_serdes_test_suite = {
+	.name = "firewire-packet-serdes",
+	.test_cases = packet_serdes_test_cases,
+};
+kunit_test_suite(packet_serdes_test_suite);
+
+MODULE_DESCRIPTION("FireWire packet serialization/deserialization unit test suite");
+MODULE_LICENSE("GPL");