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/input/mouse/maplemouse.c | 153 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 drivers/input/mouse/maplemouse.c (limited to 'drivers/input/mouse/maplemouse.c') diff --git a/drivers/input/mouse/maplemouse.c b/drivers/input/mouse/maplemouse.c new file mode 100644 index 000000000..0c8f7d1b0 --- /dev/null +++ b/drivers/input/mouse/maplemouse.c @@ -0,0 +1,153 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * SEGA Dreamcast mouse driver + * Based on drivers/usb/usbmouse.c + * + * Copyright (c) Yaegashi Takeshi, 2001 + * Copyright (c) Adrian McMenamin, 2008 - 2009 + */ + +#include +#include +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Adrian McMenamin "); +MODULE_DESCRIPTION("SEGA Dreamcast mouse driver"); +MODULE_LICENSE("GPL"); + +struct dc_mouse { + struct input_dev *dev; + struct maple_device *mdev; +}; + +static void dc_mouse_callback(struct mapleq *mq) +{ + int buttons, relx, rely, relz; + struct maple_device *mapledev = mq->dev; + struct dc_mouse *mse = maple_get_drvdata(mapledev); + struct input_dev *dev = mse->dev; + unsigned char *res = mq->recvbuf->buf; + + buttons = ~res[8]; + relx = *(unsigned short *)(res + 12) - 512; + rely = *(unsigned short *)(res + 14) - 512; + relz = *(unsigned short *)(res + 16) - 512; + + input_report_key(dev, BTN_LEFT, buttons & 4); + input_report_key(dev, BTN_MIDDLE, buttons & 9); + input_report_key(dev, BTN_RIGHT, buttons & 2); + input_report_rel(dev, REL_X, relx); + input_report_rel(dev, REL_Y, rely); + input_report_rel(dev, REL_WHEEL, relz); + input_sync(dev); +} + +static int dc_mouse_open(struct input_dev *dev) +{ + struct dc_mouse *mse = input_get_drvdata(dev); + + maple_getcond_callback(mse->mdev, dc_mouse_callback, HZ/50, + MAPLE_FUNC_MOUSE); + + return 0; +} + +static void dc_mouse_close(struct input_dev *dev) +{ + struct dc_mouse *mse = input_get_drvdata(dev); + + maple_getcond_callback(mse->mdev, dc_mouse_callback, 0, + MAPLE_FUNC_MOUSE); +} + +/* allow the mouse to be used */ +static int probe_maple_mouse(struct device *dev) +{ + struct maple_device *mdev = to_maple_dev(dev); + struct maple_driver *mdrv = to_maple_driver(dev->driver); + int error; + struct input_dev *input_dev; + struct dc_mouse *mse; + + mse = kzalloc_obj(*mse); + if (!mse) { + error = -ENOMEM; + goto fail; + } + + input_dev = input_allocate_device(); + if (!input_dev) { + error = -ENOMEM; + goto fail_nomem; + } + + mse->dev = input_dev; + mse->mdev = mdev; + + maple_set_drvdata(mdev, mse); + + input_set_drvdata(input_dev, mse); + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL); + input_dev->keybit[BIT_WORD(BTN_MOUSE)] = BIT_MASK(BTN_LEFT) | + BIT_MASK(BTN_RIGHT) | BIT_MASK(BTN_MIDDLE); + input_dev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y) | + BIT_MASK(REL_WHEEL); + input_dev->open = dc_mouse_open; + input_dev->close = dc_mouse_close; + input_dev->name = mdev->product_name; + input_dev->id.bustype = BUS_HOST; + error = input_register_device(input_dev); + if (error) + goto fail_register; + + mdev->driver = mdrv; + + return error; + +fail_register: + input_free_device(input_dev); + maple_set_drvdata(mdev, NULL); +fail_nomem: + kfree(mse); +fail: + return error; +} + +static int remove_maple_mouse(struct device *dev) +{ + struct maple_device *mdev = to_maple_dev(dev); + struct dc_mouse *mse = maple_get_drvdata(mdev); + + mdev->callback = NULL; + input_unregister_device(mse->dev); + maple_set_drvdata(mdev, NULL); + kfree(mse); + + return 0; +} + +static struct maple_driver dc_mouse_driver = { + .function = MAPLE_FUNC_MOUSE, + .drv = { + .name = "Dreamcast_mouse", + .probe = probe_maple_mouse, + .remove = remove_maple_mouse, + }, +}; + +static int __init dc_mouse_init(void) +{ + return maple_driver_register(&dc_mouse_driver); +} + +static void __exit dc_mouse_exit(void) +{ + maple_driver_unregister(&dc_mouse_driver); +} + +module_init(dc_mouse_init); +module_exit(dc_mouse_exit); -- cgit v1.3.1