From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- drivers/firewire/ohci-serdes-test.c | 122 ++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 drivers/firewire/ohci-serdes-test.c (limited to 'drivers/firewire/ohci-serdes-test.c') diff --git a/drivers/firewire/ohci-serdes-test.c b/drivers/firewire/ohci-serdes-test.c new file mode 100644 index 000000000..258f66861 --- /dev/null +++ b/drivers/firewire/ohci-serdes-test.c @@ -0,0 +1,122 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// +// ohci-serdes-test.c - An application of Kunit to check serialization/deserialization of data in +// buffers and registers defined in 1394 OHCI specification. +// +// Copyright (c) 2024 Takashi Sakamoto + +#include + +#include "ohci.h" + + +static void test_self_id_count_register_deserialization(struct kunit *test) +{ + const u32 expected = 0x803d0594; + + bool is_error = ohci1394_self_id_count_is_error(expected); + u8 generation = ohci1394_self_id_count_get_generation(expected); + u32 size = ohci1394_self_id_count_get_size(expected); + + KUNIT_EXPECT_TRUE(test, is_error); + KUNIT_EXPECT_EQ(test, 0x3d, generation); + KUNIT_EXPECT_EQ(test, 0x165, size); +} + +static void test_self_id_receive_buffer_deserialization(struct kunit *test) +{ + const u32 buffer[] = { + 0x0006f38b, + 0x807fcc56, + 0x7f8033a9, + 0x8145cc5e, + 0x7eba33a1, + }; + + u8 generation = ohci1394_self_id_receive_q0_get_generation(buffer[0]); + u16 timestamp = ohci1394_self_id_receive_q0_get_timestamp(buffer[0]); + + KUNIT_EXPECT_EQ(test, 0x6, generation); + KUNIT_EXPECT_EQ(test, 0xf38b, timestamp); +} + +static void test_at_data_serdes(struct kunit *test) +{ + static const __le32 expected[] = { + cpu_to_le32(0x00020e80), + cpu_to_le32(0xffc2ffff), + cpu_to_le32(0xe0000000), + }; + __le32 quadlets[] = {0, 0, 0}; + bool has_src_bus_id = ohci1394_at_data_get_src_bus_id(expected); + unsigned int speed = ohci1394_at_data_get_speed(expected); + unsigned int tlabel = ohci1394_at_data_get_tlabel(expected); + unsigned int retry = ohci1394_at_data_get_retry(expected); + unsigned int tcode = ohci1394_at_data_get_tcode(expected); + unsigned int destination_id = ohci1394_at_data_get_destination_id(expected); + u64 destination_offset = ohci1394_at_data_get_destination_offset(expected); + + KUNIT_EXPECT_FALSE(test, has_src_bus_id); + KUNIT_EXPECT_EQ(test, 0x02, speed); + KUNIT_EXPECT_EQ(test, 0x03, tlabel); + KUNIT_EXPECT_EQ(test, 0x02, retry); + KUNIT_EXPECT_EQ(test, 0x08, tcode); + + ohci1394_at_data_set_src_bus_id(quadlets, has_src_bus_id); + ohci1394_at_data_set_speed(quadlets, speed); + ohci1394_at_data_set_tlabel(quadlets, tlabel); + ohci1394_at_data_set_retry(quadlets, retry); + ohci1394_at_data_set_tcode(quadlets, tcode); + ohci1394_at_data_set_destination_id(quadlets, destination_id); + ohci1394_at_data_set_destination_offset(quadlets, destination_offset); + + KUNIT_EXPECT_MEMEQ(test, quadlets, expected, sizeof(expected)); +} + +static void test_it_data_serdes(struct kunit *test) +{ + static const __le32 expected[] = { + cpu_to_le32(0x000349a7), + cpu_to_le32(0x02300000), + }; + __le32 quadlets[] = {0, 0}; + unsigned int scode = ohci1394_it_data_get_speed(expected); + unsigned int tag = ohci1394_it_data_get_tag(expected); + unsigned int channel = ohci1394_it_data_get_channel(expected); + unsigned int tcode = ohci1394_it_data_get_tcode(expected); + unsigned int sync = ohci1394_it_data_get_sync(expected); + unsigned int data_length = ohci1394_it_data_get_data_length(expected); + + KUNIT_EXPECT_EQ(test, 0x03, scode); + KUNIT_EXPECT_EQ(test, 0x01, tag); + KUNIT_EXPECT_EQ(test, 0x09, channel); + KUNIT_EXPECT_EQ(test, 0x0a, tcode); + KUNIT_EXPECT_EQ(test, 0x7, sync); + KUNIT_EXPECT_EQ(test, 0x0230, data_length); + + ohci1394_it_data_set_speed(quadlets, scode); + ohci1394_it_data_set_tag(quadlets, tag); + ohci1394_it_data_set_channel(quadlets, channel); + ohci1394_it_data_set_tcode(quadlets, tcode); + ohci1394_it_data_set_sync(quadlets, sync); + ohci1394_it_data_set_data_length(quadlets, data_length); + + KUNIT_EXPECT_MEMEQ(test, quadlets, expected, sizeof(expected)); +} + +static struct kunit_case ohci_serdes_test_cases[] = { + KUNIT_CASE(test_self_id_count_register_deserialization), + KUNIT_CASE(test_self_id_receive_buffer_deserialization), + KUNIT_CASE(test_at_data_serdes), + KUNIT_CASE(test_it_data_serdes), + {} +}; + +static struct kunit_suite ohci_serdes_test_suite = { + .name = "firewire-ohci-serdes", + .test_cases = ohci_serdes_test_cases, +}; +kunit_test_suite(ohci_serdes_test_suite); + +MODULE_DESCRIPTION("FireWire buffers and registers serialization/deserialization unit test suite"); +MODULE_LICENSE("GPL"); -- cgit v1.3.1