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/btmrvl_debugfs.c | 193 +++++++++++++++++++++++++++++++++++++ 1 file changed, 193 insertions(+) create mode 100644 drivers/bluetooth/btmrvl_debugfs.c (limited to 'drivers/bluetooth/btmrvl_debugfs.c') diff --git a/drivers/bluetooth/btmrvl_debugfs.c b/drivers/bluetooth/btmrvl_debugfs.c new file mode 100644 index 000000000..9b3e768c0 --- /dev/null +++ b/drivers/bluetooth/btmrvl_debugfs.c @@ -0,0 +1,193 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Marvell Bluetooth driver: debugfs related functions + * + * Copyright (C) 2009, Marvell International Ltd. + **/ + +#include +#include + +#include +#include + +#include "btmrvl_drv.h" + +struct btmrvl_debugfs_data { + struct dentry *config_dir; + struct dentry *status_dir; +}; + +static ssize_t btmrvl_hscfgcmd_write(struct file *file, + const char __user *ubuf, size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + long result, ret; + + ret = kstrtol_from_user(ubuf, count, 10, &result); + if (ret) + return ret; + + priv->btmrvl_dev.hscfgcmd = result; + + if (priv->btmrvl_dev.hscfgcmd) { + btmrvl_prepare_command(priv); + wake_up_interruptible(&priv->main_thread.wait_q); + } + + return count; +} + +static ssize_t btmrvl_hscfgcmd_read(struct file *file, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + char buf[16]; + int ret; + + ret = snprintf(buf, sizeof(buf) - 1, "%d\n", + priv->btmrvl_dev.hscfgcmd); + + return simple_read_from_buffer(userbuf, count, ppos, buf, ret); +} + +static const struct file_operations btmrvl_hscfgcmd_fops = { + .read = btmrvl_hscfgcmd_read, + .write = btmrvl_hscfgcmd_write, + .open = simple_open, + .llseek = default_llseek, +}; + +static ssize_t btmrvl_pscmd_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + long result, ret; + + ret = kstrtol_from_user(ubuf, count, 10, &result); + if (ret) + return ret; + + priv->btmrvl_dev.pscmd = result; + + if (priv->btmrvl_dev.pscmd) { + btmrvl_prepare_command(priv); + wake_up_interruptible(&priv->main_thread.wait_q); + } + + return count; + +} + +static ssize_t btmrvl_pscmd_read(struct file *file, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + char buf[16]; + int ret; + + ret = snprintf(buf, sizeof(buf) - 1, "%d\n", priv->btmrvl_dev.pscmd); + + return simple_read_from_buffer(userbuf, count, ppos, buf, ret); +} + +static const struct file_operations btmrvl_pscmd_fops = { + .read = btmrvl_pscmd_read, + .write = btmrvl_pscmd_write, + .open = simple_open, + .llseek = default_llseek, +}; + +static ssize_t btmrvl_hscmd_write(struct file *file, const char __user *ubuf, + size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + long result, ret; + + ret = kstrtol_from_user(ubuf, count, 10, &result); + if (ret) + return ret; + + priv->btmrvl_dev.hscmd = result; + if (priv->btmrvl_dev.hscmd) { + btmrvl_prepare_command(priv); + wake_up_interruptible(&priv->main_thread.wait_q); + } + + return count; +} + +static ssize_t btmrvl_hscmd_read(struct file *file, char __user *userbuf, + size_t count, loff_t *ppos) +{ + struct btmrvl_private *priv = file->private_data; + char buf[16]; + int ret; + + ret = snprintf(buf, sizeof(buf) - 1, "%d\n", priv->btmrvl_dev.hscmd); + + return simple_read_from_buffer(userbuf, count, ppos, buf, ret); +} + +static const struct file_operations btmrvl_hscmd_fops = { + .read = btmrvl_hscmd_read, + .write = btmrvl_hscmd_write, + .open = simple_open, + .llseek = default_llseek, +}; + +void btmrvl_debugfs_init(struct hci_dev *hdev) +{ + struct btmrvl_private *priv = hci_get_drvdata(hdev); + struct btmrvl_debugfs_data *dbg; + + if (!hdev->debugfs) + return; + + dbg = kzalloc_obj(*dbg); + priv->debugfs_data = dbg; + + if (!dbg) { + BT_ERR("Can not allocate memory for btmrvl_debugfs_data."); + return; + } + + dbg->config_dir = debugfs_create_dir("config", hdev->debugfs); + + debugfs_create_u8("psmode", 0644, dbg->config_dir, + &priv->btmrvl_dev.psmode); + debugfs_create_file("pscmd", 0644, dbg->config_dir, + priv, &btmrvl_pscmd_fops); + debugfs_create_x16("gpiogap", 0644, dbg->config_dir, + &priv->btmrvl_dev.gpio_gap); + debugfs_create_u8("hsmode", 0644, dbg->config_dir, + &priv->btmrvl_dev.hsmode); + debugfs_create_file("hscmd", 0644, dbg->config_dir, + priv, &btmrvl_hscmd_fops); + debugfs_create_file("hscfgcmd", 0644, dbg->config_dir, + priv, &btmrvl_hscfgcmd_fops); + + dbg->status_dir = debugfs_create_dir("status", hdev->debugfs); + debugfs_create_u8("curpsmode", 0444, dbg->status_dir, + &priv->adapter->psmode); + debugfs_create_u8("psstate", 0444, dbg->status_dir, + &priv->adapter->ps_state); + debugfs_create_u8("hsstate", 0444, dbg->status_dir, + &priv->adapter->hs_state); + debugfs_create_u8("txdnldready", 0444, dbg->status_dir, + &priv->btmrvl_dev.tx_dnld_rdy); +} + +void btmrvl_debugfs_remove(struct hci_dev *hdev) +{ + struct btmrvl_private *priv = hci_get_drvdata(hdev); + struct btmrvl_debugfs_data *dbg = priv->debugfs_data; + + if (!dbg) + return; + + debugfs_remove_recursive(dbg->config_dir); + debugfs_remove_recursive(dbg->status_dir); + + kfree(dbg); +} -- cgit v1.3.1