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/device-attribute-test.c | 253 +++++++++++++++++++++++++++++++ 1 file changed, 253 insertions(+) create mode 100644 drivers/firewire/device-attribute-test.c (limited to 'drivers/firewire/device-attribute-test.c') diff --git a/drivers/firewire/device-attribute-test.c b/drivers/firewire/device-attribute-test.c new file mode 100644 index 000000000..97478a96d --- /dev/null +++ b/drivers/firewire/device-attribute-test.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// device-attribute-test.c - An application of Kunit to test implementation for device attributes. +// +// Copyright (c) 2023 Takashi Sakamoto +// +// This file can not be built independently since it is intentionally included in core-device.c. + +#include + +// Configuration ROM for AV/C Devices 1.0 (Dec. 12, 2000, 1394 Trading Association) +// Annex C:Configuration ROM example(informative) +// C.1 Simple AV/C device +// +// Copied from the documentation. +static const u32 simple_avc_config_rom[] = { + 0x0404eabf, + 0x31333934, + 0xe0646102, + 0xffffffff, + 0xffffffff, + 0x00063287, // root directory. + 0x03ffffff, + 0x8100000a, + 0x17ffffff, + 0x8100000e, + 0x0c0083c0, + 0xd1000001, + 0x0004442d, // unit 0 directory. + 0x1200a02d, + 0x13010001, + 0x17ffffff, + 0x81000007, + 0x0005c915, // leaf for textual descriptor. + 0x00000000, + 0x00000000, + 0x56656e64, + 0x6f72204e, + 0x616d6500, + 0x00057f16, // leaf for textual descriptor. + 0x00000000, + 0x00000000, + 0x4d6f6465, + 0x6c204e61, + 0x6d650000, +}; + +// Ibid. +// Annex A:Consideration for configuration ROM reader design (informative) +// A.1 Vendor directory +// +// Written by hand. +static const u32 legacy_avc_config_rom[] = { + 0x04199fe7, + 0x31333934, + 0xe0644000, + 0x00112233, + 0x44556677, + 0x0005dace, // root directory. + 0x03012345, + 0x0c0083c0, + 0x8d000009, + 0xd1000002, + 0xc3000004, + 0x0002e107, // unit 0 directory. + 0x12abcdef, + 0x13543210, + 0x0002cb73, // vendor directory. + 0x17fedcba, + 0x81000004, + 0x00026dc1, // leaf for EUI-64. + 0x00112233, + 0x44556677, + 0x00050e84, // leaf for textual descriptor. + 0x00000000, + 0x00000000, + 0x41424344, + 0x45464748, + 0x494a0000, +}; + +static void device_attr_simple_avc(struct kunit *test) +{ + static const struct fw_device node = { + .device = { + .type = &fw_device_type, + }, + .config_rom = simple_avc_config_rom, + .config_rom_length = sizeof(simple_avc_config_rom), + }; + static const struct fw_unit unit0 = { + .device = { + .type = &fw_unit_type, + .parent = (struct device *)&node.device, + }, + .directory = &simple_avc_config_rom[12], + }; + struct device *node_dev = (struct device *)&node.device; + struct device *unit0_dev = (struct device *)&unit0.device; + static const int unit0_expected_ids[] = {0x00ffffff, 0x00ffffff, 0x0000a02d, 0x00010001}; + char *buf = kunit_kzalloc(test, PAGE_SIZE, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + int ids[4] = {0, 0, 0, 0}; + + // Ensure associations for node and unit devices. + + KUNIT_ASSERT_TRUE(test, is_fw_device(node_dev)); + KUNIT_ASSERT_FALSE(test, is_fw_unit(node_dev)); + KUNIT_ASSERT_PTR_EQ(test, fw_device(node_dev), &node); + + KUNIT_ASSERT_FALSE(test, is_fw_device(unit0_dev)); + KUNIT_ASSERT_TRUE(test, is_fw_unit(unit0_dev)); + KUNIT_ASSERT_PTR_EQ(test, fw_parent_device((&unit0)), &node); + KUNIT_ASSERT_PTR_EQ(test, fw_unit(unit0_dev), &unit0); + + // For entries in root directory. + + // Vendor immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(node_dev, &config_rom_attributes[0].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0xffffff\n"); + + // Model immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(node_dev, &config_rom_attributes[4].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0xffffff\n"); + + // Descriptor leaf entry for vendor is found. + KUNIT_EXPECT_GT(test, show_text_leaf(node_dev, &config_rom_attributes[5].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "Vendor Name\n"); + + // Descriptor leaf entry for model is found. + KUNIT_EXPECT_GT(test, show_text_leaf(node_dev, &config_rom_attributes[6].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "Model Name\n"); + + // For entries in unit 0 directory. + + // Vendor immediate entry is not found. + KUNIT_EXPECT_LT(test, show_immediate(unit0_dev, &config_rom_attributes[0].attr, buf), 0); + + // Model immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(unit0_dev, &config_rom_attributes[4].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0xffffff\n"); + + // Descriptor leaf entry for vendor is not found. + KUNIT_EXPECT_LT(test, show_text_leaf(unit0_dev, &config_rom_attributes[5].attr, buf), 0); + + // Descriptor leaf entry for model is found. + KUNIT_EXPECT_GT(test, show_text_leaf(unit0_dev, &config_rom_attributes[6].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "Model Name\n"); + + // Specifier_ID immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(unit0_dev, &config_rom_attributes[2].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0x00a02d\n"); + + // Version immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(unit0_dev, &config_rom_attributes[3].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0x010001\n"); + + kunit_kfree(test, buf); + + get_modalias_ids(&unit0, ids); + KUNIT_EXPECT_MEMEQ(test, ids, unit0_expected_ids, sizeof(ids)); +} + +static void device_attr_legacy_avc(struct kunit *test) +{ + static const struct fw_device node = { + .device = { + .type = &fw_device_type, + }, + .config_rom = legacy_avc_config_rom, + .config_rom_length = sizeof(legacy_avc_config_rom), + }; + static const struct fw_unit unit0 = { + .device = { + .type = &fw_unit_type, + .parent = (struct device *)&node.device, + }, + .directory = &legacy_avc_config_rom[11], + }; + struct device *node_dev = (struct device *)&node.device; + struct device *unit0_dev = (struct device *)&unit0.device; + static const int unit0_expected_ids[] = {0x00012345, 0x00fedcba, 0x00abcdef, 0x00543210}; + char *buf = kunit_kzalloc(test, PAGE_SIZE, GFP_KERNEL); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + int ids[4] = {0, 0, 0, 0}; + + // Ensure associations for node and unit devices. + + KUNIT_ASSERT_TRUE(test, is_fw_device(node_dev)); + KUNIT_ASSERT_FALSE(test, is_fw_unit(node_dev)); + KUNIT_ASSERT_PTR_EQ(test, fw_device((node_dev)), &node); + + KUNIT_ASSERT_FALSE(test, is_fw_device(unit0_dev)); + KUNIT_ASSERT_TRUE(test, is_fw_unit(unit0_dev)); + KUNIT_ASSERT_PTR_EQ(test, fw_parent_device((&unit0)), &node); + KUNIT_ASSERT_PTR_EQ(test, fw_unit(unit0_dev), &unit0); + + // For entries in root directory. + + // Vendor immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(node_dev, &config_rom_attributes[0].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0x012345\n"); + + // Model immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(node_dev, &config_rom_attributes[4].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0xfedcba\n"); + + // Descriptor leaf entry for vendor is not found. + KUNIT_EXPECT_LT(test, show_text_leaf(node_dev, &config_rom_attributes[5].attr, buf), 0); + + // Descriptor leaf entry for model is found. + KUNIT_EXPECT_GT(test, show_text_leaf(node_dev, &config_rom_attributes[6].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "ABCDEFGHIJ\n"); + + // For entries in unit 0 directory. + + // Vendor immediate entry is not found. + KUNIT_EXPECT_LT(test, show_immediate(unit0_dev, &config_rom_attributes[0].attr, buf), 0); + + // Model immediate entry is not found. + KUNIT_EXPECT_LT(test, show_immediate(unit0_dev, &config_rom_attributes[4].attr, buf), 0); + + // Descriptor leaf entry for vendor is not found. + KUNIT_EXPECT_LT(test, show_text_leaf(unit0_dev, &config_rom_attributes[5].attr, buf), 0); + + // Descriptor leaf entry for model is not found. + KUNIT_EXPECT_LT(test, show_text_leaf(unit0_dev, &config_rom_attributes[6].attr, buf), 0); + + // Specifier_ID immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(unit0_dev, &config_rom_attributes[2].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0xabcdef\n"); + + // Version immediate entry is found. + KUNIT_EXPECT_GT(test, show_immediate(unit0_dev, &config_rom_attributes[3].attr, buf), 0); + KUNIT_EXPECT_STREQ(test, buf, "0x543210\n"); + + kunit_kfree(test, buf); + + get_modalias_ids(&unit0, ids); + KUNIT_EXPECT_MEMEQ(test, ids, unit0_expected_ids, sizeof(ids)); +} + +static struct kunit_case device_attr_test_cases[] = { + KUNIT_CASE(device_attr_simple_avc), + KUNIT_CASE(device_attr_legacy_avc), + {} +}; + +static struct kunit_suite device_attr_test_suite = { + .name = "firewire-device-attribute", + .test_cases = device_attr_test_cases, +}; +kunit_test_suite(device_attr_test_suite); -- cgit v1.3.1