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/serio/pcips2.c | 217 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 217 insertions(+) create mode 100644 drivers/input/serio/pcips2.c (limited to 'drivers/input/serio/pcips2.c') diff --git a/drivers/input/serio/pcips2.c b/drivers/input/serio/pcips2.c new file mode 100644 index 000000000..78f47b0ca --- /dev/null +++ b/drivers/input/serio/pcips2.c @@ -0,0 +1,217 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * linux/drivers/input/serio/pcips2.c + * + * Copyright (C) 2003 Russell King, All Rights Reserved. + * + * I'm not sure if this is a generic PS/2 PCI interface or specific to + * the Mobility Electronics docking station. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define PS2_CTRL (0) +#define PS2_STATUS (1) +#define PS2_DATA (2) + +#define PS2_CTRL_CLK (1<<0) +#define PS2_CTRL_DAT (1<<1) +#define PS2_CTRL_TXIRQ (1<<2) +#define PS2_CTRL_ENABLE (1<<3) +#define PS2_CTRL_RXIRQ (1<<4) + +#define PS2_STAT_CLK (1<<0) +#define PS2_STAT_DAT (1<<1) +#define PS2_STAT_PARITY (1<<2) +#define PS2_STAT_RXFULL (1<<5) +#define PS2_STAT_TXBUSY (1<<6) +#define PS2_STAT_TXEMPTY (1<<7) + +struct pcips2_data { + struct serio *io; + unsigned int base; + struct pci_dev *dev; +}; + +static int pcips2_write(struct serio *io, unsigned char val) +{ + struct pcips2_data *ps2if = io->port_data; + unsigned int stat; + + do { + stat = inb(ps2if->base + PS2_STATUS); + cpu_relax(); + } while (!(stat & PS2_STAT_TXEMPTY)); + + outb(val, ps2if->base + PS2_DATA); + + return 0; +} + +static irqreturn_t pcips2_interrupt(int irq, void *devid) +{ + struct pcips2_data *ps2if = devid; + unsigned char status, scancode; + int handled = 0; + + do { + unsigned int flag; + + status = inb(ps2if->base + PS2_STATUS); + if (!(status & PS2_STAT_RXFULL)) + break; + handled = 1; + scancode = inb(ps2if->base + PS2_DATA); + if (status == 0xff && scancode == 0xff) + break; + + flag = (status & PS2_STAT_PARITY) ? 0 : SERIO_PARITY; + + if (hweight8(scancode) & 1) + flag ^= SERIO_PARITY; + + serio_interrupt(ps2if->io, scancode, flag); + } while (1); + return IRQ_RETVAL(handled); +} + +static void pcips2_flush_input(struct pcips2_data *ps2if) +{ + unsigned char status, scancode; + + do { + status = inb(ps2if->base + PS2_STATUS); + if (!(status & PS2_STAT_RXFULL)) + break; + scancode = inb(ps2if->base + PS2_DATA); + if (status == 0xff && scancode == 0xff) + break; + } while (1); +} + +static int pcips2_open(struct serio *io) +{ + struct pcips2_data *ps2if = io->port_data; + int ret, val = 0; + + outb(PS2_CTRL_ENABLE, ps2if->base); + pcips2_flush_input(ps2if); + + ret = request_irq(ps2if->dev->irq, pcips2_interrupt, IRQF_SHARED, + "pcips2", ps2if); + if (ret == 0) + val = PS2_CTRL_ENABLE | PS2_CTRL_RXIRQ; + + outb(val, ps2if->base); + + return ret; +} + +static void pcips2_close(struct serio *io) +{ + struct pcips2_data *ps2if = io->port_data; + + outb(0, ps2if->base); + + free_irq(ps2if->dev->irq, ps2if); +} + +static int pcips2_probe(struct pci_dev *dev, const struct pci_device_id *id) +{ + struct pcips2_data *ps2if; + struct serio *serio; + int ret; + + ret = pci_enable_device(dev); + if (ret) + goto out; + + ret = pci_request_regions(dev, "pcips2"); + if (ret) + goto disable; + + ps2if = kzalloc_obj(*ps2if); + serio = kzalloc_obj(*serio); + if (!ps2if || !serio) { + ret = -ENOMEM; + goto release; + } + + + serio->id.type = SERIO_8042; + serio->write = pcips2_write; + serio->open = pcips2_open; + serio->close = pcips2_close; + strscpy(serio->name, pci_name(dev), sizeof(serio->name)); + strscpy(serio->phys, dev_name(&dev->dev), sizeof(serio->phys)); + serio->port_data = ps2if; + serio->dev.parent = &dev->dev; + ps2if->io = serio; + ps2if->dev = dev; + ps2if->base = pci_resource_start(dev, 0); + + pci_set_drvdata(dev, ps2if); + + serio_register_port(ps2if->io); + return 0; + + release: + kfree(ps2if); + kfree(serio); + pci_release_regions(dev); + disable: + pci_disable_device(dev); + out: + return ret; +} + +static void pcips2_remove(struct pci_dev *dev) +{ + struct pcips2_data *ps2if = pci_get_drvdata(dev); + + serio_unregister_port(ps2if->io); + kfree(ps2if); + pci_release_regions(dev); + pci_disable_device(dev); +} + +static const struct pci_device_id pcips2_ids[] = { + { + .vendor = 0x14f2, /* MOBILITY */ + .device = 0x0123, /* Keyboard */ + .subvendor = PCI_ANY_ID, + .subdevice = PCI_ANY_ID, + .class = PCI_CLASS_INPUT_KEYBOARD << 8, + .class_mask = 0xffff00, + }, + { + .vendor = 0x14f2, /* MOBILITY */ + .device = 0x0124, /* Mouse */ + .subvendor = PCI_ANY_ID, + .subdevice = PCI_ANY_ID, + .class = PCI_CLASS_INPUT_MOUSE << 8, + .class_mask = 0xffff00, + }, + { 0, } +}; +MODULE_DEVICE_TABLE(pci, pcips2_ids); + +static struct pci_driver pcips2_driver = { + .name = "pcips2", + .id_table = pcips2_ids, + .probe = pcips2_probe, + .remove = pcips2_remove, +}; + +module_pci_driver(pcips2_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Russell King "); +MODULE_DESCRIPTION("PCI PS/2 keyboard/mouse driver"); -- cgit v1.3.1