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/bluetooth/hci_serdev.c | 414 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 414 insertions(+) create mode 100644 drivers/bluetooth/hci_serdev.c (limited to 'drivers/bluetooth/hci_serdev.c') diff --git a/drivers/bluetooth/hci_serdev.c b/drivers/bluetooth/hci_serdev.c new file mode 100644 index 000000000..d2eaf2f12 --- /dev/null +++ b/drivers/bluetooth/hci_serdev.c @@ -0,0 +1,414 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Bluetooth HCI serdev driver lib + * + * Copyright (C) 2017 Linaro, Ltd., Rob Herring + * + * Based on hci_ldisc.c: + * + * Copyright (C) 2000-2001 Qualcomm Incorporated + * Copyright (C) 2002-2003 Maxim Krasnyansky + * Copyright (C) 2004-2005 Marcel Holtmann + */ + +#include +#include +#include +#include + +#include +#include + +#include "hci_uart.h" + +static inline void hci_uart_tx_complete(struct hci_uart *hu, int pkt_type) +{ + struct hci_dev *hdev = hu->hdev; + + /* Update HCI stat counters */ + switch (pkt_type) { + case HCI_COMMAND_PKT: + hdev->stat.cmd_tx++; + break; + + case HCI_ACLDATA_PKT: + hdev->stat.acl_tx++; + break; + + case HCI_SCODATA_PKT: + hdev->stat.sco_tx++; + break; + } +} + +static inline struct sk_buff *hci_uart_dequeue(struct hci_uart *hu) +{ + struct sk_buff *skb = hu->tx_skb; + + if (!skb) { + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) + skb = hu->proto->dequeue(hu); + } else + hu->tx_skb = NULL; + + return skb; +} + +static void hci_uart_write_work(struct work_struct *work) +{ + struct hci_uart *hu = container_of(work, struct hci_uart, write_work); + struct serdev_device *serdev = hu->serdev; + struct hci_dev *hdev = hu->hdev; + struct sk_buff *skb; + + /* REVISIT: + * should we cope with bad skbs or ->write() returning an error value? + */ + do { + clear_bit(HCI_UART_TX_WAKEUP, &hu->tx_state); + + while ((skb = hci_uart_dequeue(hu))) { + int len; + + len = serdev_device_write_buf(serdev, + skb->data, skb->len); + hdev->stat.byte_tx += len; + + skb_pull(skb, len); + if (skb->len) { + hu->tx_skb = skb; + break; + } + + hci_uart_tx_complete(hu, hci_skb_pkt_type(skb)); + kfree_skb(skb); + } + + clear_bit(HCI_UART_SENDING, &hu->tx_state); + } while (test_bit(HCI_UART_TX_WAKEUP, &hu->tx_state)); +} + +/* ------- Interface to HCI layer ------ */ + +/* Reset device */ +static int hci_uart_flush(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + + BT_DBG("hdev %p serdev %p", hdev, hu->serdev); + + if (hu->tx_skb) { + kfree_skb(hu->tx_skb); hu->tx_skb = NULL; + } + + /* Flush any pending characters in the driver and discipline. */ + serdev_device_write_flush(hu->serdev); + + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) + hu->proto->flush(hu); + + return 0; +} + +/* Initialize device */ +static int hci_uart_open(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + int err; + + BT_DBG("%s %p", hdev->name, hdev); + + /* When Quirk HCI_QUIRK_NON_PERSISTENT_SETUP is set by + * driver, BT SoC is completely turned OFF during + * BT OFF. Upon next BT ON UART port should be opened. + */ + if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) { + err = serdev_device_open(hu->serdev); + if (err) + return err; + set_bit(HCI_UART_PROTO_READY, &hu->flags); + } + + /* Undo clearing this from hci_uart_close() */ + hdev->flush = hci_uart_flush; + + return 0; +} + +/* Close device */ +static int hci_uart_close(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + + BT_DBG("hdev %p", hdev); + + if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) + return 0; + + hci_uart_flush(hdev); + hdev->flush = NULL; + + /* When QUIRK HCI_QUIRK_NON_PERSISTENT_SETUP is set by driver, + * BT SOC is completely powered OFF during BT OFF, holding port + * open may drain the battery. + */ + if (hci_test_quirk(hdev, HCI_QUIRK_NON_PERSISTENT_SETUP)) { + clear_bit(HCI_UART_PROTO_READY, &hu->flags); + serdev_device_close(hu->serdev); + } + + return 0; +} + +/* Send frames from HCI layer */ +static int hci_uart_send_frame(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + + BT_DBG("%s: type %d len %d", hdev->name, hci_skb_pkt_type(skb), + skb->len); + + hu->proto->enqueue(hu, skb); + + hci_uart_tx_wakeup(hu); + + return 0; +} + +static int hci_uart_setup(struct hci_dev *hdev) +{ + struct hci_uart *hu = hci_get_drvdata(hdev); + struct hci_rp_read_local_version *ver; + struct sk_buff *skb; + unsigned int speed; + int err; + + /* Init speed if any */ + if (hu->init_speed) + speed = hu->init_speed; + else if (hu->proto->init_speed) + speed = hu->proto->init_speed; + else + speed = 0; + + if (speed) + serdev_device_set_baudrate(hu->serdev, speed); + + /* Operational speed if any */ + if (hu->oper_speed) + speed = hu->oper_speed; + else if (hu->proto->oper_speed) + speed = hu->proto->oper_speed; + else + speed = 0; + + if (hu->proto->set_baudrate && speed) { + err = hu->proto->set_baudrate(hu, speed); + if (err) + bt_dev_err(hdev, "Failed to set baudrate"); + else + serdev_device_set_baudrate(hu->serdev, speed); + } + + if (hu->proto->setup) + return hu->proto->setup(hu); + + if (!test_bit(HCI_UART_VND_DETECT, &hu->hdev_flags)) + return 0; + + skb = __hci_cmd_sync(hdev, HCI_OP_READ_LOCAL_VERSION, 0, NULL, + HCI_INIT_TIMEOUT); + if (IS_ERR(skb)) { + bt_dev_err(hdev, "Reading local version info failed (%ld)", + PTR_ERR(skb)); + return PTR_ERR(skb); + } + + if (skb->len != sizeof(*ver)) + bt_dev_err(hdev, "Event length mismatch for version info"); + + kfree_skb(skb); + return 0; +} + +/* Check if the device is wakeable */ +static bool hci_uart_wakeup(struct hci_dev *hdev) +{ + /* HCI UART devices are assumed to be wakeable by default. + * Implement wakeup callback to override this behavior. + */ + return true; +} + +/** hci_uart_write_wakeup - transmit buffer wakeup + * @serdev: serial device + * + * This function is called by the serdev framework when it accepts + * more data being sent. + */ +static void hci_uart_write_wakeup(struct serdev_device *serdev) +{ + struct hci_uart *hu = serdev_device_get_drvdata(serdev); + + BT_DBG(""); + + if (!hu || serdev != hu->serdev) { + WARN_ON(1); + return; + } + + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) + hci_uart_tx_wakeup(hu); +} + +/** hci_uart_receive_buf - receive buffer wakeup + * @serdev: serial device + * @data: pointer to received data + * @count: count of received data in bytes + * + * This function is called by the serdev framework when it received data + * in the RX buffer. + * + * Return: number of processed bytes + */ +static size_t hci_uart_receive_buf(struct serdev_device *serdev, + const u8 *data, size_t count) +{ + struct hci_uart *hu = serdev_device_get_drvdata(serdev); + + if (!hu || serdev != hu->serdev) { + WARN_ON(1); + return 0; + } + + if (!test_bit(HCI_UART_PROTO_READY, &hu->flags)) + return 0; + + /* It does not need a lock here as it is already protected by a mutex in + * tty caller + */ + hu->proto->recv(hu, data, count); + + if (hu->hdev) + hu->hdev->stat.byte_rx += count; + + return count; +} + +static const struct serdev_device_ops hci_serdev_client_ops = { + .receive_buf = hci_uart_receive_buf, + .write_wakeup = hci_uart_write_wakeup, +}; + +int hci_uart_register_device_priv(struct hci_uart *hu, + const struct hci_uart_proto *p, + int sizeof_priv) +{ + int err; + struct hci_dev *hdev; + + BT_DBG(""); + + serdev_device_set_client_ops(hu->serdev, &hci_serdev_client_ops); + + if (percpu_init_rwsem(&hu->proto_lock)) + return -ENOMEM; + + err = serdev_device_open(hu->serdev); + if (err) + goto err_rwsem; + + err = p->open(hu); + if (err) + goto err_open; + + hu->proto = p; + set_bit(HCI_UART_PROTO_READY, &hu->flags); + + /* Initialize and register HCI device */ + hdev = hci_alloc_dev_priv(sizeof_priv); + if (!hdev) { + BT_ERR("Can't allocate HCI device"); + err = -ENOMEM; + goto err_alloc; + } + + hu->hdev = hdev; + + hdev->bus = HCI_UART; + hci_set_drvdata(hdev, hu); + + INIT_WORK(&hu->init_ready, hci_uart_init_work); + INIT_WORK(&hu->write_work, hci_uart_write_work); + + /* Only when vendor specific setup callback is provided, consider + * the manufacturer information valid. This avoids filling in the + * value for Ericsson when nothing is specified. + */ + if (hu->proto->setup) + hdev->manufacturer = hu->proto->manufacturer; + + hdev->open = hci_uart_open; + hdev->close = hci_uart_close; + hdev->flush = hci_uart_flush; + hdev->send = hci_uart_send_frame; + hdev->setup = hci_uart_setup; + if (!hdev->wakeup) + hdev->wakeup = hci_uart_wakeup; + SET_HCIDEV_DEV(hdev, &hu->serdev->dev); + + if (test_bit(HCI_UART_NO_SUSPEND_NOTIFIER, &hu->flags)) + hci_set_quirk(hdev, HCI_QUIRK_NO_SUSPEND_NOTIFIER); + + if (test_bit(HCI_UART_RAW_DEVICE, &hu->hdev_flags)) + hci_set_quirk(hdev, HCI_QUIRK_RAW_DEVICE); + + if (test_bit(HCI_UART_EXT_CONFIG, &hu->hdev_flags)) + hci_set_quirk(hdev, HCI_QUIRK_EXTERNAL_CONFIG); + + if (test_bit(HCI_UART_INIT_PENDING, &hu->hdev_flags)) + return 0; + + if (hci_register_dev(hdev) < 0) { + BT_ERR("Can't register HCI device"); + err = -ENODEV; + goto err_register; + } + + set_bit(HCI_UART_REGISTERED, &hu->flags); + + return 0; + +err_register: + hci_free_dev(hdev); +err_alloc: + clear_bit(HCI_UART_PROTO_READY, &hu->flags); + p->close(hu); +err_open: + serdev_device_close(hu->serdev); +err_rwsem: + percpu_free_rwsem(&hu->proto_lock); + return err; +} +EXPORT_SYMBOL_GPL(hci_uart_register_device_priv); + +void hci_uart_unregister_device(struct hci_uart *hu) +{ + struct hci_dev *hdev = hu->hdev; + + cancel_work_sync(&hu->init_ready); + if (test_bit(HCI_UART_REGISTERED, &hu->flags)) + hci_unregister_dev(hdev); + hci_free_dev(hdev); + + cancel_work_sync(&hu->write_work); + + hu->proto->close(hu); + + if (test_bit(HCI_UART_PROTO_READY, &hu->flags)) { + clear_bit(HCI_UART_PROTO_READY, &hu->flags); + serdev_device_close(hu->serdev); + } + percpu_free_rwsem(&hu->proto_lock); +} +EXPORT_SYMBOL_GPL(hci_uart_unregister_device); -- cgit v1.3.1