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/bluetooth/btrsi.c | 186 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 186 insertions(+) create mode 100644 drivers/bluetooth/btrsi.c (limited to 'drivers/bluetooth/btrsi.c') diff --git a/drivers/bluetooth/btrsi.c b/drivers/bluetooth/btrsi.c new file mode 100644 index 000000000..3f802b7c8 --- /dev/null +++ b/drivers/bluetooth/btrsi.c @@ -0,0 +1,186 @@ +// SPDX-License-Identifier: ISC +/* + * Copyright (c) 2017 Redpine Signals Inc. + * + */ +#include +#include +#include +#include +#include +#include + +#define RSI_DMA_ALIGN 8 +#define RSI_FRAME_DESC_SIZE 16 +#define RSI_HEADROOM_FOR_BT_HAL (RSI_FRAME_DESC_SIZE + RSI_DMA_ALIGN) + +struct rsi_hci_adapter { + void *priv; + struct rsi_proto_ops *proto_ops; + struct hci_dev *hdev; +}; + +static int rsi_hci_open(struct hci_dev *hdev) +{ + return 0; +} + +static int rsi_hci_close(struct hci_dev *hdev) +{ + return 0; +} + +static int rsi_hci_flush(struct hci_dev *hdev) +{ + return 0; +} + +static int rsi_hci_send_pkt(struct hci_dev *hdev, struct sk_buff *skb) +{ + struct rsi_hci_adapter *h_adapter = hci_get_drvdata(hdev); + struct sk_buff *new_skb = NULL; + + switch (hci_skb_pkt_type(skb)) { + 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; + } + + if (skb_headroom(skb) < RSI_HEADROOM_FOR_BT_HAL) { + /* Insufficient skb headroom - allocate a new skb */ + new_skb = skb_realloc_headroom(skb, RSI_HEADROOM_FOR_BT_HAL); + if (unlikely(!new_skb)) + return -ENOMEM; + bt_cb(new_skb)->pkt_type = hci_skb_pkt_type(skb); + kfree_skb(skb); + skb = new_skb; + if (!IS_ALIGNED((unsigned long)skb->data, RSI_DMA_ALIGN)) { + u8 *skb_data = skb->data; + int skb_len = skb->len; + + skb_push(skb, RSI_DMA_ALIGN); + skb_pull(skb, PTR_ALIGN(skb->data, + RSI_DMA_ALIGN) - skb->data); + memmove(skb->data, skb_data, skb_len); + skb_trim(skb, skb_len); + } + } + + return h_adapter->proto_ops->coex_send_pkt(h_adapter->priv, skb, + RSI_BT_Q); +} + +static int rsi_hci_recv_pkt(void *priv, const u8 *pkt) +{ + struct rsi_hci_adapter *h_adapter = priv; + struct hci_dev *hdev = h_adapter->hdev; + struct sk_buff *skb; + int pkt_len = get_unaligned_le16(pkt) & 0x0fff; + + skb = dev_alloc_skb(pkt_len); + if (!skb) + return -ENOMEM; + + memcpy(skb->data, pkt + RSI_FRAME_DESC_SIZE, pkt_len); + skb_put(skb, pkt_len); + h_adapter->hdev->stat.byte_rx += skb->len; + + hci_skb_pkt_type(skb) = pkt[14]; + + return hci_recv_frame(hdev, skb); +} + +static int rsi_hci_attach(void *priv, struct rsi_proto_ops *ops) +{ + struct rsi_hci_adapter *h_adapter = NULL; + struct hci_dev *hdev; + int err = 0; + + h_adapter = kzalloc_obj(*h_adapter); + if (!h_adapter) + return -ENOMEM; + + h_adapter->priv = priv; + h_adapter->proto_ops = ops; + + hdev = hci_alloc_dev(); + if (!hdev) { + BT_ERR("Failed to alloc HCI device"); + goto err; + } + + h_adapter->hdev = hdev; + + if (ops->get_host_intf(priv) == RSI_HOST_INTF_SDIO) + hdev->bus = HCI_SDIO; + else + hdev->bus = HCI_USB; + + hci_set_drvdata(hdev, h_adapter); + hdev->open = rsi_hci_open; + hdev->close = rsi_hci_close; + hdev->flush = rsi_hci_flush; + hdev->send = rsi_hci_send_pkt; + + err = hci_register_dev(hdev); + if (err < 0) { + BT_ERR("HCI registration failed with errcode %d", err); + hci_free_dev(hdev); + goto err; + } + + ops->set_bt_context(priv, h_adapter); + + return 0; +err: + h_adapter->hdev = NULL; + kfree(h_adapter); + return -EINVAL; +} + +static void rsi_hci_detach(void *priv) +{ + struct rsi_hci_adapter *h_adapter = priv; + struct hci_dev *hdev; + + if (!h_adapter) + return; + + hdev = h_adapter->hdev; + if (hdev) { + hci_unregister_dev(hdev); + hci_free_dev(hdev); + h_adapter->hdev = NULL; + } + + kfree(h_adapter); +} + +const struct rsi_mod_ops rsi_bt_ops = { + .attach = rsi_hci_attach, + .detach = rsi_hci_detach, + .recv_pkt = rsi_hci_recv_pkt, +}; +EXPORT_SYMBOL(rsi_bt_ops); + +static int rsi_91x_bt_module_init(void) +{ + return 0; +} + +static void rsi_91x_bt_module_exit(void) +{ + return; +} + +module_init(rsi_91x_bt_module_init); +module_exit(rsi_91x_bt_module_exit); +MODULE_AUTHOR("Redpine Signals Inc"); +MODULE_DESCRIPTION("RSI BT driver"); +MODULE_LICENSE("Dual BSD/GPL"); -- cgit v1.3.1