From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/acpi/device_sysfs.c | 651 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 651 insertions(+) create mode 100644 drivers/acpi/device_sysfs.c (limited to 'drivers/acpi/device_sysfs.c') diff --git a/drivers/acpi/device_sysfs.c b/drivers/acpi/device_sysfs.c new file mode 100644 index 000000000..c5434b998 --- /dev/null +++ b/drivers/acpi/device_sysfs.c @@ -0,0 +1,651 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * drivers/acpi/device_sysfs.c - ACPI device sysfs attributes and modalias. + * + * Copyright (C) 2015, Intel Corp. + * Author: Mika Westerberg + * Author: Rafael J. Wysocki + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include +#include +#include +#include + +#include "internal.h" + +static ssize_t acpi_object_path(acpi_handle handle, char *buf) +{ + struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; + int result; + + result = acpi_get_name(handle, ACPI_FULL_PATHNAME, &path); + if (result) + return result; + + result = sysfs_emit(buf, "%s\n", (char *)path.pointer); + kfree(path.pointer); + return result; +} + +struct acpi_data_node_attr { + struct attribute attr; + ssize_t (*show)(struct acpi_data_node *, char *); + ssize_t (*store)(struct acpi_data_node *, const char *, size_t count); +}; + +#define DATA_NODE_ATTR(_name) \ + static struct acpi_data_node_attr data_node_##_name = \ + __ATTR(_name, 0444, data_node_show_##_name, NULL) + +static ssize_t data_node_show_path(struct acpi_data_node *dn, char *buf) +{ + return dn->handle ? acpi_object_path(dn->handle, buf) : 0; +} + +DATA_NODE_ATTR(path); + +static struct attribute *acpi_data_node_default_attrs[] = { + &data_node_path.attr, + NULL +}; +ATTRIBUTE_GROUPS(acpi_data_node_default); + +#define to_data_node(k) container_of(k, struct acpi_data_node, kobj) +#define to_attr(a) container_of(a, struct acpi_data_node_attr, attr) + +static ssize_t acpi_data_node_attr_show(struct kobject *kobj, + struct attribute *attr, char *buf) +{ + struct acpi_data_node *dn = to_data_node(kobj); + struct acpi_data_node_attr *dn_attr = to_attr(attr); + + return dn_attr->show ? dn_attr->show(dn, buf) : -ENXIO; +} + +static const struct sysfs_ops acpi_data_node_sysfs_ops = { + .show = acpi_data_node_attr_show, +}; + +static void acpi_data_node_release(struct kobject *kobj) +{ + struct acpi_data_node *dn = to_data_node(kobj); + + complete(&dn->kobj_done); +} + +static const struct kobj_type acpi_data_node_ktype = { + .sysfs_ops = &acpi_data_node_sysfs_ops, + .default_groups = acpi_data_node_default_groups, + .release = acpi_data_node_release, +}; + +static void acpi_expose_nondev_subnodes(struct kobject *kobj, + struct acpi_device_data *data) +{ + struct list_head *list = &data->subnodes; + struct acpi_data_node *dn; + + if (list_empty(list)) + return; + + list_for_each_entry(dn, list, sibling) { + int ret; + + init_completion(&dn->kobj_done); + ret = kobject_init_and_add(&dn->kobj, &acpi_data_node_ktype, + kobj, "%s", dn->name); + if (!ret) + acpi_expose_nondev_subnodes(&dn->kobj, &dn->data); + else if (dn->handle) + acpi_handle_err(dn->handle, "Failed to expose (%d)\n", ret); + } +} + +static void acpi_hide_nondev_subnodes(struct acpi_device_data *data) +{ + struct list_head *list = &data->subnodes; + struct acpi_data_node *dn; + + if (list_empty(list)) + return; + + list_for_each_entry_reverse(dn, list, sibling) { + acpi_hide_nondev_subnodes(&dn->data); + kobject_put(&dn->kobj); + } +} + +/** + * create_pnp_modalias - Create hid/cid(s) string for modalias and uevent + * @acpi_dev: ACPI device object. + * @modalias: Buffer to print into. + * @size: Size of the buffer. + * + * Creates hid/cid(s) string needed for modalias and uevent + * e.g. on a device with hid:IBM0001 and cid:ACPI0001 you get: + * char *modalias: "acpi:IBM0001:ACPI0001" + * Return: 0: no _HID and no _CID + * -EINVAL: output error + * -ENOMEM: output is truncated + */ +static int create_pnp_modalias(const struct acpi_device *acpi_dev, char *modalias, + int size) +{ + int len; + int count; + struct acpi_hardware_id *id; + + /* Avoid unnecessarily loading modules for non present devices. */ + if (!acpi_device_is_present(acpi_dev)) + return 0; + + /* + * Since we skip ACPI_DT_NAMESPACE_HID from the modalias below, 0 should + * be returned if ACPI_DT_NAMESPACE_HID is the only ACPI/PNP ID in the + * device's list. + */ + count = 0; + list_for_each_entry(id, &acpi_dev->pnp.ids, list) + if (strcmp(id->id, ACPI_DT_NAMESPACE_HID)) + count++; + + if (!count) + return 0; + + len = snprintf(modalias, size, "acpi:"); + if (len >= size) + return -ENOMEM; + + size -= len; + + list_for_each_entry(id, &acpi_dev->pnp.ids, list) { + if (!strcmp(id->id, ACPI_DT_NAMESPACE_HID)) + continue; + + count = snprintf(&modalias[len], size, "%s:", id->id); + + if (count >= size) + return -ENOMEM; + + len += count; + size -= count; + } + + return len; +} + +/** + * create_of_modalias - Creates DT compatible string for modalias and uevent + * @acpi_dev: ACPI device object. + * @modalias: Buffer to print into. + * @size: Size of the buffer. + * + * Expose DT compatible modalias as of:NnameTCcompatible. This function should + * only be called for devices having ACPI_DT_NAMESPACE_HID in their list of + * ACPI/PNP IDs. + */ +static int create_of_modalias(const struct acpi_device *acpi_dev, char *modalias, + int size) +{ + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; + const union acpi_object *of_compatible, *obj; + acpi_status status; + int len, count; + int i, nval; + char *c; + + status = acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); + if (ACPI_FAILURE(status)) + return -ENODEV; + + /* DT strings are all in lower case */ + for (c = buf.pointer; *c != '\0'; c++) + *c = tolower(*c); + + len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); + ACPI_FREE(buf.pointer); + + if (len >= size) + return -ENOMEM; + + size -= len; + + of_compatible = acpi_dev->data.of_compatible; + if (of_compatible->type == ACPI_TYPE_PACKAGE) { + nval = of_compatible->package.count; + obj = of_compatible->package.elements; + } else { /* Must be ACPI_TYPE_STRING. */ + nval = 1; + obj = of_compatible; + } + for (i = 0; i < nval; i++, obj++) { + count = snprintf(&modalias[len], size, "C%s", + obj->string.pointer); + + if (count >= size) + return -ENOMEM; + + len += count; + size -= count; + } + + return len; +} + +int __acpi_device_uevent_modalias(const struct acpi_device *adev, + struct kobj_uevent_env *env) +{ + int len; + + if (!adev) + return -ENODEV; + + if (list_empty(&adev->pnp.ids)) + return 0; + + if (add_uevent_var(env, "MODALIAS=")) + return -ENOMEM; + + if (adev->data.of_compatible) + len = create_of_modalias(adev, &env->buf[env->buflen - 1], + sizeof(env->buf) - env->buflen); + else + len = create_pnp_modalias(adev, &env->buf[env->buflen - 1], + sizeof(env->buf) - env->buflen); + if (len < 0) + return len; + + env->buflen += len; + + return 0; +} + +/** + * acpi_device_uevent_modalias - uevent modalias for ACPI-enumerated devices. + * @dev: Struct device to get ACPI device node. + * @env: Environment variables of the kobject uevent. + * + * Create the uevent modalias field for ACPI-enumerated devices. + * + * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with + * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". + */ +int acpi_device_uevent_modalias(const struct device *dev, struct kobj_uevent_env *env) +{ + return __acpi_device_uevent_modalias(acpi_companion_match(dev), env); +} +EXPORT_SYMBOL_GPL(acpi_device_uevent_modalias); + +static int __acpi_device_modalias(const struct acpi_device *adev, char *buf, int size) +{ + int len, count; + + if (!adev) + return -ENODEV; + + if (list_empty(&adev->pnp.ids)) + return 0; + + len = create_pnp_modalias(adev, buf, size - 1); + if (len < 0) { + return len; + } else if (len > 0) { + buf[len++] = '\n'; + size -= len; + } + if (!adev->data.of_compatible) + return len; + + count = create_of_modalias(adev, buf + len, size - 1); + if (count < 0) { + return count; + } else if (count > 0) { + len += count; + buf[len++] = '\n'; + } + + return len; +} + +/** + * acpi_device_modalias - modalias sysfs attribute for ACPI-enumerated devices. + * @dev: Struct device to get ACPI device node. + * @buf: The buffer to save pnp_modalias and of_modalias. + * @size: Size of buffer. + * + * Create the modalias sysfs attribute for ACPI-enumerated devices. + * + * Because other buses do not support ACPI HIDs & CIDs, e.g. for a device with + * hid:IBM0001 and cid:ACPI0001 you get: "acpi:IBM0001:ACPI0001". + */ +int acpi_device_modalias(struct device *dev, char *buf, int size) +{ + return __acpi_device_modalias(acpi_companion_match(dev), buf, size); +} +EXPORT_SYMBOL_GPL(acpi_device_modalias); + +static ssize_t +modalias_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + return __acpi_device_modalias(to_acpi_device(dev), buf, 1024); +} +static DEVICE_ATTR_RO(modalias); + +static ssize_t real_power_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *adev = to_acpi_device(dev); + int state; + int ret; + + ret = acpi_device_get_power(adev, &state); + if (ret) + return ret; + + return sysfs_emit(buf, "%s\n", acpi_power_state_string(state)); +} + +static DEVICE_ATTR_RO(real_power_state); + +static ssize_t power_state_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *adev = to_acpi_device(dev); + + return sysfs_emit(buf, "%s\n", acpi_power_state_string(adev->power.state)); +} + +static DEVICE_ATTR_RO(power_state); + +static ssize_t +eject_store(struct device *d, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct acpi_device *acpi_device = to_acpi_device(d); + acpi_object_type not_used; + acpi_status status; + + if (!count || buf[0] != '1') + return -EINVAL; + + if ((!acpi_device->handler || !acpi_device->handler->hotplug.enabled) + && !d->driver) + return -ENODEV; + + status = acpi_get_type(acpi_device->handle, ¬_used); + if (ACPI_FAILURE(status) || !acpi_device->flags.ejectable) + return -ENODEV; + + acpi_dev_get(acpi_device); + status = acpi_hotplug_schedule(acpi_device, ACPI_OST_EC_OSPM_EJECT); + if (ACPI_SUCCESS(status)) + return count; + + acpi_dev_put(acpi_device); + acpi_evaluate_ost(acpi_device->handle, ACPI_OST_EC_OSPM_EJECT, + ACPI_OST_SC_NON_SPECIFIC_FAILURE, NULL); + return status == AE_NO_MEMORY ? -ENOMEM : -EAGAIN; +} + +static DEVICE_ATTR_WO(eject); + +static ssize_t +hid_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sysfs_emit(buf, "%s\n", acpi_device_hid(acpi_dev)); +} +static DEVICE_ATTR_RO(hid); + +static ssize_t cid_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_device_info *info = NULL; + ssize_t len = 0; + + acpi_get_object_info(acpi_dev->handle, &info); + if (!info) + return 0; + + if (info->valid & ACPI_VALID_CID) { + struct acpi_pnp_device_id_list *cid_list = &info->compatible_id_list; + int i; + + for (i = 0; i < cid_list->count - 1; i++) + len += sysfs_emit_at(buf, len, "%s,", cid_list->ids[i].string); + + len += sysfs_emit_at(buf, len, "%s\n", cid_list->ids[i].string); + } + + kfree(info); + + return len; +} +static DEVICE_ATTR_RO(cid); + +static ssize_t uid_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return sysfs_emit(buf, "%s\n", acpi_device_uid(acpi_dev)); +} +static DEVICE_ATTR_RO(uid); + +static ssize_t adr_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + if (acpi_dev->pnp.bus_address > U32_MAX) + return sysfs_emit(buf, "0x%016llx\n", acpi_dev->pnp.bus_address); + else + return sysfs_emit(buf, "0x%08llx\n", acpi_dev->pnp.bus_address); +} +static DEVICE_ATTR_RO(adr); + +static ssize_t path_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + + return acpi_object_path(acpi_dev->handle, buf); +} +static DEVICE_ATTR_RO(path); + +/* sysfs file that shows description text from the ACPI _STR method */ +static ssize_t description_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; + union acpi_object *str_obj; + acpi_status status; + int result; + + status = acpi_evaluate_object_typed(acpi_dev->handle, "_STR", + NULL, &buffer, + ACPI_TYPE_BUFFER); + if (ACPI_FAILURE(status)) + return -EIO; + + str_obj = buffer.pointer; + + /* + * The _STR object contains a Unicode identifier for a device. + * We need to convert to utf-8 so it can be displayed. + */ + result = utf16s_to_utf8s( + (wchar_t *)str_obj->buffer.pointer, + str_obj->buffer.length, + UTF16_LITTLE_ENDIAN, buf, + PAGE_SIZE - 1); + + buf[result++] = '\n'; + + ACPI_FREE(str_obj); + + return result; +} +static DEVICE_ATTR_RO(description); + +static ssize_t +sun_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + acpi_status status; + unsigned long long sun; + + status = acpi_evaluate_integer(acpi_dev->handle, "_SUN", NULL, &sun); + if (ACPI_FAILURE(status)) + return -EIO; + + return sysfs_emit(buf, "%llu\n", sun); +} +static DEVICE_ATTR_RO(sun); + +static ssize_t +hrv_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + acpi_status status; + unsigned long long hrv; + + status = acpi_evaluate_integer(acpi_dev->handle, "_HRV", NULL, &hrv); + if (ACPI_FAILURE(status)) + return -EIO; + + return sysfs_emit(buf, "%llu\n", hrv); +} +static DEVICE_ATTR_RO(hrv); + +static ssize_t status_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct acpi_device *acpi_dev = to_acpi_device(dev); + acpi_status status; + unsigned long long sta; + + status = acpi_evaluate_integer(acpi_dev->handle, "_STA", NULL, &sta); + if (ACPI_FAILURE(status)) + return -EIO; + + return sysfs_emit(buf, "%llu\n", sta); +} +static DEVICE_ATTR_RO(status); + +static struct attribute *acpi_attrs[] = { + &dev_attr_path.attr, + &dev_attr_hid.attr, + &dev_attr_cid.attr, + &dev_attr_modalias.attr, + &dev_attr_description.attr, + &dev_attr_adr.attr, + &dev_attr_uid.attr, + &dev_attr_sun.attr, + &dev_attr_hrv.attr, + &dev_attr_status.attr, + &dev_attr_eject.attr, + &dev_attr_power_state.attr, + &dev_attr_real_power_state.attr, + NULL +}; + +static bool acpi_show_attr(struct acpi_device *dev, const struct device_attribute *attr) +{ + /* + * Devices gotten from FADT don't have a "path" attribute + */ + if (attr == &dev_attr_path) + return dev->handle; + + if (attr == &dev_attr_hid || attr == &dev_attr_modalias) + return !list_empty(&dev->pnp.ids); + + if (attr == &dev_attr_description) + return acpi_has_method(dev->handle, "_STR"); + + if (attr == &dev_attr_adr) + return dev->pnp.type.bus_address; + + if (attr == &dev_attr_uid) + return acpi_device_uid(dev); + + if (attr == &dev_attr_sun) + return acpi_has_method(dev->handle, "_SUN"); + + if (attr == &dev_attr_hrv) + return acpi_has_method(dev->handle, "_HRV"); + + if (attr == &dev_attr_status) + return acpi_has_method(dev->handle, "_STA"); + + if (attr == &dev_attr_cid) + return acpi_has_method(dev->handle, "_CID"); + + /* + * If device has _EJ0, 'eject' file is created that is used to trigger + * hot-removal function from userland. + */ + if (attr == &dev_attr_eject) + return acpi_has_method(dev->handle, "_EJ0"); + + if (attr == &dev_attr_power_state) + return dev->flags.power_manageable; + + if (attr == &dev_attr_real_power_state) + return dev->flags.power_manageable && dev->power.flags.power_resources; + + dev_warn_once(&dev->dev, "Unexpected attribute: %s\n", attr->attr.name); + return false; +} + +static umode_t acpi_attr_is_visible(struct kobject *kobj, + struct attribute *attr, + int attrno) +{ + struct acpi_device *dev = to_acpi_device(kobj_to_dev(kobj)); + + if (acpi_show_attr(dev, container_of(attr, struct device_attribute, attr))) + return attr->mode; + else + return 0; +} + +static const struct attribute_group acpi_group = { + .attrs = acpi_attrs, + .is_visible = acpi_attr_is_visible, +}; + +const struct attribute_group *acpi_groups[] = { + &acpi_group, + NULL +}; + +/** + * acpi_device_setup_files - Create sysfs attributes of an ACPI device. + * @dev: ACPI device object. + */ +void acpi_device_setup_files(struct acpi_device *dev) +{ + acpi_expose_nondev_subnodes(&dev->dev.kobj, &dev->data); +} + +/** + * acpi_device_remove_files - Remove sysfs attributes of an ACPI device. + * @dev: ACPI device object. + */ +void acpi_device_remove_files(struct acpi_device *dev) +{ + acpi_hide_nondev_subnodes(&dev->data); +} -- cgit v1.3.1