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/amimouse.c | 150 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 150 insertions(+) create mode 100644 drivers/input/mouse/amimouse.c (limited to 'drivers/input/mouse/amimouse.c') diff --git a/drivers/input/mouse/amimouse.c b/drivers/input/mouse/amimouse.c new file mode 100644 index 000000000..d203c2a6c --- /dev/null +++ b/drivers/input/mouse/amimouse.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Amiga mouse driver for Linux/m68k + * + * Copyright (c) 2000-2002 Vojtech Pavlik + * + * Based on the work of: + * Michael Rausch James Banks + * Matther Dillon David Giller + * Nathan Laredo Linus Torvalds + * Johan Myreen Jes Sorensen + * Russell King + */ + + +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +MODULE_AUTHOR("Vojtech Pavlik "); +MODULE_DESCRIPTION("Amiga mouse driver"); +MODULE_LICENSE("GPL"); + +static int amimouse_lastx, amimouse_lasty; + +static irqreturn_t amimouse_interrupt(int irq, void *data) +{ + struct input_dev *dev = data; + unsigned short joy0dat, potgor; + int nx, ny, dx, dy; + + joy0dat = amiga_custom.joy0dat; + + nx = joy0dat & 0xff; + ny = joy0dat >> 8; + + dx = nx - amimouse_lastx; + dy = ny - amimouse_lasty; + + if (dx < -127) dx = (256 + nx) - amimouse_lastx; + if (dx > 127) dx = (nx - 256) - amimouse_lastx; + if (dy < -127) dy = (256 + ny) - amimouse_lasty; + if (dy > 127) dy = (ny - 256) - amimouse_lasty; + + amimouse_lastx = nx; + amimouse_lasty = ny; + + potgor = amiga_custom.potgor; + + input_report_rel(dev, REL_X, dx); + input_report_rel(dev, REL_Y, dy); + + input_report_key(dev, BTN_LEFT, ciaa.pra & 0x40); + input_report_key(dev, BTN_MIDDLE, potgor & 0x0100); + input_report_key(dev, BTN_RIGHT, potgor & 0x0400); + + input_sync(dev); + + return IRQ_HANDLED; +} + +static int amimouse_open(struct input_dev *dev) +{ + unsigned short joy0dat; + int error; + + joy0dat = amiga_custom.joy0dat; + + amimouse_lastx = joy0dat & 0xff; + amimouse_lasty = joy0dat >> 8; + + error = request_irq(IRQ_AMIGA_VERTB, amimouse_interrupt, 0, "amimouse", + dev); + if (error) + dev_err(&dev->dev, "Can't allocate irq %d\n", IRQ_AMIGA_VERTB); + + return error; +} + +static void amimouse_close(struct input_dev *dev) +{ + free_irq(IRQ_AMIGA_VERTB, dev); +} + +static int __init amimouse_probe(struct platform_device *pdev) +{ + int err; + struct input_dev *dev; + + dev = input_allocate_device(); + if (!dev) + return -ENOMEM; + + dev->name = pdev->name; + dev->phys = "amimouse/input0"; + dev->id.bustype = BUS_AMIGA; + dev->id.vendor = 0x0001; + dev->id.product = 0x0002; + dev->id.version = 0x0100; + + dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REL); + dev->relbit[0] = BIT_MASK(REL_X) | BIT_MASK(REL_Y); + dev->keybit[BIT_WORD(BTN_LEFT)] = BIT_MASK(BTN_LEFT) | + BIT_MASK(BTN_MIDDLE) | BIT_MASK(BTN_RIGHT); + dev->open = amimouse_open; + dev->close = amimouse_close; + dev->dev.parent = &pdev->dev; + + err = input_register_device(dev); + if (err) { + input_free_device(dev); + return err; + } + + platform_set_drvdata(pdev, dev); + + return 0; +} + +static void __exit amimouse_remove(struct platform_device *pdev) +{ + struct input_dev *dev = platform_get_drvdata(pdev); + + input_unregister_device(dev); +} + +/* + * amimouse_remove() lives in .exit.text. For drivers registered via + * module_platform_driver_probe() this is ok because they cannot get unbound at + * runtime. So mark the driver struct with __refdata to prevent modpost + * triggering a section mismatch warning. + */ +static struct platform_driver amimouse_driver __refdata = { + .remove = __exit_p(amimouse_remove), + .driver = { + .name = "amiga-mouse", + }, +}; + +module_platform_driver_probe(amimouse_driver, amimouse_probe); + +MODULE_ALIAS("platform:amiga-mouse"); -- cgit v1.3.1