From 22098763a10d9c1340827fcf6edab66f153b27f0 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 13 Sep 2026 12:27:00 -0700 Subject: Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Don't destroy user event fields when removal fails User event fields are destroyed before the event is removed from visibility. But that can fail leaving the still visible event with no fields. Move the destroying of the fields to after the event is successfully removed from visibility. - Initialize function graph state is fork before calling copy_exec_state() For non-CLONE_VM forks, copy_exec_state() allocates a new task_exec_state. If that allocation fails, ftrace_graph_exit_task() will free the tasks ret_stack pointer. Since that pointer is still using the parent's ret_stack, it mistakenly frees the parent's pointer too. Call ftrace_graph_init() on the task first which will NULL out the new tasks's ret_stack and if the copy fails, it will not free anything. - Remove FGRAPH_MAX_INDEX The macro FGRAPH_MAX_INDEX was added but never used. Remove it. - Save ent_size in function graph printing of nested functions The function graph tracer needs to look at the next event to see if the next event is the return of the current function entry. If it is, it prints a single line: ktime_get(); Otherwise it prints it like a nested function: tick_nohz_irq_exit() { ktime_get(); kcpustat_irq_exit(); } In order to look at the next event, it must save the current event so that it has the information to print from it. It saves the event in the iterator descriptor called "ent". What it doesn't save is the ent_size of the event which is now used to know if the function graph arguments are to be printed. The peek doesn't save the size so the size used happens to be that of the size of the last event that was seen. Save the entry event size in the iterator descriptor so that the correct size is used. - Fix several errors with freeing data in the histogram code The histogram code had a lot of leaked or or incorrect accounting when failures happen. Correct them. - Fix histogram regression of .percent and .graph modifiers Up until 6.3 histogram values could have "percent" or "graph" modifiers that changed how they were printed. But a change that added restricting histograms values from being strings, stack traces and other modifiers inadvertently prevented them from using the percent and graph modifiers, which were legal use cases for values. Put back the percent and graph modifiers. - Fix various typos in the comments - Set the trace_clock before initializing a histogram with clock argument The histogram API allows the user to specific which trace clock to use via a "clock=" string. The histogram is set up first before the clock is checked. If the passed in clock is not valid, it exits without fully fixing up the histogram leaving it on the list and a use-after-free can trigger. Update the clock argument first and if it fails then exit gracefully before the histogram trigger is placed on any lists. - Restore :mod: trailer after parsing in ftrace_set_clr_event The function ftrace_set_clr_event() modifies the parse string and needs to put it back to what was passed in. It searches for ":mod:" via a strsep() but fails to put back the first ':' in the string. Add back the ':' in the passed in string. - Take trace_array reference when opening a tracer options file The options files are dynamically created and some tracers add their own options. When a tracer adds their own list of options, the trace_array holding them has an array to hold the list of options for each tracer. This array increases in size via a krealloc(), and the new entry gets a newly allocated array to hold the options of the new tracer being added. The element in each entry of the tracer's option array holds a pointer back to the trace_array, a pointer to the tracer it is associated to, a pointer to the flags of the option. The issue is that these arrays are freed when the trace_array is freed when its instance it represents is removed from the instances directory. There's a race that an open of one of these options files can happen when the instance is being removed. Add a new helper function to be called by the open function of the options file to iterate all existing trace_arrays under a lock and find the one that has the given option element in one of it's tracer arrays. If found, then update the associated trace_array's reference counter to keep it from being freed. If not found, have the open call return -ENODEV. - Disable interrupts when acquiring the lock in rb_wake_up_waiters() The function rb_wake_up_waiters() assumes it will be called in interrupt context and does not disable irqs when taking cpu_buffer->reader_lock, which can be called in hard interrupt context. The issue is in PREEMPT_RT, this function is called in thread context leaving this lock open to a deadlock. Take the lock with interrupts disabled. - Use rcu_assign_pointer() for tmp_ops filter hash The tmp_ops used in update_ftrace_direct_mod() assigns its filter_hash field directly, but that field is annotated as __rcu and sparse complains. Assign it with rcu_assign_pointer() - Fix use-after-free in enable_trigger_private_data_free() The trace_event_call is accessed through the event_trigger_data's trace_event_file pointer to put the trace_event_call on freeing. The issue is that the trace_event_file data may have been freed already causing a use-after-free. Add a field to the event_trigger_data that points directly to the trace_event_call so that it can decrement its reference directly without needing to go through the trace_event_file. - Fix accounting of buffer data remote headers trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount the number of pages is needed for the asked for size as it doesn't take into account the meta data on each page. Add a helper function to do the calculation properly and use that in these functions. - Catch nr_page_va overflow in ring_buffer_desc sizing The number of pages per remote ring buffer is capped by ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to overflow that field would silently allocate a descriptor smaller than what was asked for. - Do not resize the subbuf order if any per_cpu buffer is disabled The mmapping of ring buffers disables resizing the subbuffers, but it is done per-cpu whereas the subbuf size change is done for all the per_cpu buffers under the buffer->mutex. It could change the size of some while the mapping is happening on others. Have the resize of the subbuf order check all the per_cpu buffers under the lock to see if any of them is disabled before starting and causing an inconsistency between buffers that are being mapped. * tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits) ring-buffer: Check resize_disabled before publishing the new subbuf order tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing tracing/remotes: Account for ring buffer page header in size calculation tracing: Don't dereference trace_event_file in deferred trigger free ftrace: Use rcu_assign_pointer() for tmp_ops filter hash ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters() tracing: Take trace_array reference when opening a tracer options file tracing: Fix ring_buffer_read_page_size() kernel-doc tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event() tracing: Fix memory corruption from a "STACKTRACE" histogram key tracing: Fix memory corruption from the histogram stacktrace modifier tracing: Undo the registration when enabling the histogram trigger fails tracing: Take the reference before publishing the named histogram trigger tracing: Set the trace clock before registering the histogram trigger tracing: Fix typo "preceeded" in comment tracing: Fix typo "availabe" in comment tracing: Let histogram values keep the percent and graph modifiers tracing: Keep the entry count when the histogram stats allocation fails tracing: Free histogram the field rejected for a bad modifier tracing: Free histogram the var ref when its initialization fails ... --- drivers/firmware/raspberrypi.c | 415 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 415 insertions(+) create mode 100644 drivers/firmware/raspberrypi.c (limited to 'drivers/firmware/raspberrypi.c') diff --git a/drivers/firmware/raspberrypi.c b/drivers/firmware/raspberrypi.c new file mode 100644 index 000000000..0aa322e9a --- /dev/null +++ b/drivers/firmware/raspberrypi.c @@ -0,0 +1,415 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Defines interfaces for interacting with the Raspberry Pi firmware's + * property channel. + * + * Copyright © 2015 Broadcom + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf)) +#define MBOX_CHAN(msg) ((msg) & 0xf) +#define MBOX_DATA28(msg) ((msg) & ~0xf) +#define MBOX_CHAN_PROPERTY 8 + +static struct platform_device *rpi_hwmon; +static struct platform_device *rpi_clk; + +struct rpi_firmware { + struct mbox_client cl; + struct mbox_chan *chan; /* The property channel. */ + struct completion c; + u32 enabled; + + struct kref consumers; +}; + +static DEFINE_MUTEX(transaction_lock); + +static void response_callback(struct mbox_client *cl, void *msg) +{ + struct rpi_firmware *fw = container_of(cl, struct rpi_firmware, cl); + complete(&fw->c); +} + +/* + * Sends a request to the firmware through the BCM2835 mailbox driver, + * and synchronously waits for the reply. + */ +static int +rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data) +{ + u32 message = MBOX_MSG(chan, data); + int ret; + + WARN_ON(data & 0xf); + + mutex_lock(&transaction_lock); + reinit_completion(&fw->c); + ret = mbox_send_message(fw->chan, &message); + if (ret >= 0) { + if (wait_for_completion_timeout(&fw->c, HZ)) { + ret = 0; + } else { + ret = -ETIMEDOUT; + } + } else { + dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret); + } + mutex_unlock(&transaction_lock); + + return ret; +} + +/** + * rpi_firmware_property_list - Submit firmware property list + * @fw: Pointer to firmware structure from rpi_firmware_get(). + * @data: Buffer holding tags. + * @tag_size: Size of tags buffer. + * + * Submits a set of concatenated tags to the VPU firmware through the + * mailbox property interface. + * + * The buffer header and the ending tag are added by this function and + * don't need to be supplied, just the actual tags for your operation. + * See struct rpi_firmware_property_tag_header for the per-tag + * structure. + */ +int rpi_firmware_property_list(struct rpi_firmware *fw, + void *data, size_t tag_size) +{ + size_t size = tag_size + 12; + u32 *buf; + dma_addr_t bus_addr; + int ret; + + /* Packets are processed a dword at a time. */ + if (size & 3) + return -EINVAL; + + buf = dma_alloc_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size), + &bus_addr, GFP_ATOMIC); + if (!buf) + return -ENOMEM; + + /* The firmware will error out without parsing in this case. */ + WARN_ON(size >= 1024 * 1024); + + buf[0] = size; + buf[1] = RPI_FIRMWARE_STATUS_REQUEST; + memcpy(&buf[2], data, tag_size); + buf[size / 4 - 1] = RPI_FIRMWARE_PROPERTY_END; + wmb(); + + ret = rpi_firmware_transaction(fw, MBOX_CHAN_PROPERTY, bus_addr); + + rmb(); + memcpy(data, &buf[2], tag_size); + if (ret == 0 && buf[1] != RPI_FIRMWARE_STATUS_SUCCESS) { + /* + * The tag name here might not be the one causing the + * error, if there were multiple tags in the request. + * But single-tag is the most common, so go with it. + */ + dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n", + buf[2], buf[1]); + ret = -EINVAL; + } else if (ret == -ETIMEDOUT) { + WARN_ONCE(1, "Firmware transaction 0x%08x timeout", buf[2]); + } + + dma_free_coherent(fw->chan->mbox->dev, PAGE_ALIGN(size), buf, bus_addr); + + return ret; +} +EXPORT_SYMBOL_GPL(rpi_firmware_property_list); + +/** + * rpi_firmware_property - Submit single firmware property + * @fw: Pointer to firmware structure from rpi_firmware_get(). + * @tag: One of enum_mbox_property_tag. + * @tag_data: Tag data buffer. + * @buf_size: Buffer size. + * + * Submits a single tag to the VPU firmware through the mailbox + * property interface. + * + * This is a convenience wrapper around + * rpi_firmware_property_list() to avoid some of the + * boilerplate in property calls. + */ +int rpi_firmware_property(struct rpi_firmware *fw, + u32 tag, void *tag_data, size_t buf_size) +{ + struct rpi_firmware_property_tag_header *header; + int ret; + + /* Some mailboxes can use over 1k bytes. Rather than checking + * size and using stack or kmalloc depending on requirements, + * just use kmalloc. Mailboxes don't get called enough to worry + * too much about the time taken in the allocation. + */ + void *data = kmalloc(sizeof(*header) + buf_size, GFP_KERNEL); + + if (!data) + return -ENOMEM; + + header = data; + header->tag = tag; + header->buf_size = buf_size; + header->req_resp_size = 0; + memcpy(data + sizeof(*header), tag_data, buf_size); + + ret = rpi_firmware_property_list(fw, data, buf_size + sizeof(*header)); + + memcpy(tag_data, data + sizeof(*header), buf_size); + + kfree(data); + + return ret; +} +EXPORT_SYMBOL_GPL(rpi_firmware_property); + +static void +rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) +{ + time64_t date_and_time; + u32 packet; + int ret = rpi_firmware_property(fw, + RPI_FIRMWARE_GET_FIRMWARE_REVISION, + &packet, sizeof(packet)); + + if (ret) + return; + + /* This is not compatible with y2038 */ + date_and_time = packet; + dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &date_and_time); +} + +static void +rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw) +{ + u32 packet; + int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_THROTTLED, + &packet, sizeof(packet)); + + if (ret) + return; + + rpi_hwmon = platform_device_register_data(dev, "raspberrypi-hwmon", + -1, NULL, 0); +} + +static void rpi_register_clk_driver(struct device *dev) +{ + struct device_node *firmware; + + /* + * Earlier DTs don't have a node for the firmware clocks but + * rely on us creating a platform device by hand. If we do + * have a node for the firmware clocks, just bail out here. + */ + firmware = of_get_compatible_child(dev->of_node, + "raspberrypi,firmware-clocks"); + if (firmware) { + of_node_put(firmware); + return; + } + + rpi_clk = platform_device_register_data(dev, "raspberrypi-clk", + -1, NULL, 0); +} + +unsigned int rpi_firmware_clk_get_max_rate(struct rpi_firmware *fw, unsigned int id) +{ + struct rpi_firmware_clk_rate_request msg = + RPI_FIRMWARE_CLK_RATE_REQUEST(id); + int ret; + + ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_MAX_CLOCK_RATE, + &msg, sizeof(msg)); + if (ret) + /* + * If our firmware doesn't support that operation, or fails, we + * assume the maximum clock rate is absolute maximum we can + * store over our type. + */ + return UINT_MAX; + + return le32_to_cpu(msg.rate); +} +EXPORT_SYMBOL_GPL(rpi_firmware_clk_get_max_rate); + +static void rpi_firmware_delete(struct kref *kref) +{ + struct rpi_firmware *fw = container_of(kref, struct rpi_firmware, + consumers); + + mbox_free_channel(fw->chan); + kfree(fw); +} + +void rpi_firmware_put(struct rpi_firmware *fw) +{ + kref_put(&fw->consumers, rpi_firmware_delete); +} +EXPORT_SYMBOL_GPL(rpi_firmware_put); + +static void devm_rpi_firmware_put(void *data) +{ + struct rpi_firmware *fw = data; + + rpi_firmware_put(fw); +} + +static int rpi_firmware_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct rpi_firmware *fw; + + /* + * Memory will be freed by rpi_firmware_delete() once all users have + * released their firmware handles. Don't use devm_kzalloc() here. + */ + fw = kzalloc_obj(*fw); + if (!fw) + return -ENOMEM; + + fw->cl.dev = dev; + fw->cl.rx_callback = response_callback; + fw->cl.tx_block = true; + + fw->chan = mbox_request_channel(&fw->cl, 0); + if (IS_ERR(fw->chan)) { + int ret = PTR_ERR(fw->chan); + kfree(fw); + return dev_err_probe(dev, ret, "Failed to get mbox channel\n"); + } + + init_completion(&fw->c); + kref_init(&fw->consumers); + + platform_set_drvdata(pdev, fw); + + rpi_firmware_print_firmware_revision(fw); + rpi_register_hwmon_driver(dev, fw); + rpi_register_clk_driver(dev); + + return 0; +} + +static void rpi_firmware_shutdown(struct platform_device *pdev) +{ + struct rpi_firmware *fw = platform_get_drvdata(pdev); + + if (!fw) + return; + + rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0); +} + +static void rpi_firmware_remove(struct platform_device *pdev) +{ + struct rpi_firmware *fw = platform_get_drvdata(pdev); + + platform_device_unregister(rpi_hwmon); + rpi_hwmon = NULL; + platform_device_unregister(rpi_clk); + rpi_clk = NULL; + + rpi_firmware_put(fw); +} + +static const struct of_device_id rpi_firmware_of_match[] = { + { .compatible = "raspberrypi,bcm2835-firmware", }, + {}, +}; +MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); + +struct device_node *rpi_firmware_find_node(void) +{ + return of_find_matching_node(NULL, rpi_firmware_of_match); +} +EXPORT_SYMBOL_GPL(rpi_firmware_find_node); + +/** + * rpi_firmware_get - Get pointer to rpi_firmware structure. + * @firmware_node: Pointer to the firmware Device Tree node. + * + * The reference to rpi_firmware has to be released with rpi_firmware_put(). + * + * Returns NULL is the firmware device is not ready. + */ +struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) +{ + struct platform_device *pdev = of_find_device_by_node(firmware_node); + struct rpi_firmware *fw; + + if (!pdev) + return NULL; + + fw = platform_get_drvdata(pdev); + if (!fw) + goto err_put_device; + + if (!kref_get_unless_zero(&fw->consumers)) + goto err_put_device; + + put_device(&pdev->dev); + + return fw; + +err_put_device: + put_device(&pdev->dev); + return NULL; +} +EXPORT_SYMBOL_GPL(rpi_firmware_get); + +/** + * devm_rpi_firmware_get - Get pointer to rpi_firmware structure. + * @dev: The firmware device structure + * @firmware_node: Pointer to the firmware Device Tree node. + * + * Returns NULL is the firmware device is not ready. + */ +struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, + struct device_node *firmware_node) +{ + struct rpi_firmware *fw; + + fw = rpi_firmware_get(firmware_node); + if (!fw) + return NULL; + + if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw)) + return NULL; + + return fw; +} +EXPORT_SYMBOL_GPL(devm_rpi_firmware_get); + +static struct platform_driver rpi_firmware_driver = { + .driver = { + .name = "raspberrypi-firmware", + .of_match_table = rpi_firmware_of_match, + }, + .probe = rpi_firmware_probe, + .shutdown = rpi_firmware_shutdown, + .remove = rpi_firmware_remove, +}; +module_platform_driver(rpi_firmware_driver); + +MODULE_AUTHOR("Eric Anholt "); +MODULE_DESCRIPTION("Raspberry Pi firmware driver"); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1