From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- drivers/misc/phantom.c | 564 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 564 insertions(+) create mode 100644 drivers/misc/phantom.c (limited to 'drivers/misc/phantom.c') diff --git a/drivers/misc/phantom.c b/drivers/misc/phantom.c new file mode 100644 index 000000000..331cae539 --- /dev/null +++ b/drivers/misc/phantom.c @@ -0,0 +1,564 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2005-2007 Jiri Slaby + * + * You need a userspace library to cooperate with this driver. It (and other + * info) may be obtained here: + * http://www.fi.muni.cz/~xslaby/phantom.html + * or alternatively, you might use OpenHaptics provided by Sensable. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define PHANTOM_VERSION "n0.9.8" + +#define PHANTOM_MAX_MINORS 8 + +#define PHN_IRQCTL 0x4c /* irq control in caddr space */ + +#define PHB_RUNNING 1 +#define PHB_NOT_OH 2 + +static DEFINE_MUTEX(phantom_mutex); +static int phantom_major; + +static const struct class phantom_class = { + .name = "phantom", +}; + +struct phantom_device { + unsigned int opened; + void __iomem *caddr; + u32 __iomem *iaddr; + u32 __iomem *oaddr; + unsigned long status; + atomic_t counter; + + wait_queue_head_t wait; + struct cdev cdev; + + struct mutex open_lock; + spinlock_t regs_lock; + + /* used in NOT_OH mode */ + struct phm_regs oregs; + u32 ctl_reg; +}; + +static unsigned char phantom_devices[PHANTOM_MAX_MINORS]; + +static int phantom_status(struct phantom_device *dev, unsigned long newstat) +{ + pr_debug("phantom_status %lx %lx\n", dev->status, newstat); + + if (!(dev->status & PHB_RUNNING) && (newstat & PHB_RUNNING)) { + atomic_set(&dev->counter, 0); + iowrite32(PHN_CTL_IRQ, dev->iaddr + PHN_CONTROL); + iowrite32(0x43, dev->caddr + PHN_IRQCTL); + ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */ + } else if ((dev->status & PHB_RUNNING) && !(newstat & PHB_RUNNING)) { + iowrite32(0, dev->caddr + PHN_IRQCTL); + ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */ + } + + dev->status = newstat; + + return 0; +} + +/* + * File ops + */ + +static long phantom_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + struct phantom_device *dev = file->private_data; + struct phm_regs rs; + struct phm_reg r; + void __user *argp = (void __user *)arg; + unsigned long flags; + unsigned int i; + + switch (cmd) { + case PHN_SETREG: + case PHN_SET_REG: + if (copy_from_user(&r, argp, sizeof(r))) + return -EFAULT; + + if (r.reg > 7) + return -EINVAL; + + spin_lock_irqsave(&dev->regs_lock, flags); + if (r.reg == PHN_CONTROL && (r.value & PHN_CTL_IRQ) && + phantom_status(dev, dev->status | PHB_RUNNING)){ + spin_unlock_irqrestore(&dev->regs_lock, flags); + return -ENODEV; + } + + pr_debug("phantom: writing %x to %u\n", r.value, r.reg); + + /* preserve amp bit (don't allow to change it when in NOT_OH) */ + if (r.reg == PHN_CONTROL && (dev->status & PHB_NOT_OH)) { + r.value &= ~PHN_CTL_AMP; + r.value |= dev->ctl_reg & PHN_CTL_AMP; + dev->ctl_reg = r.value; + } + + iowrite32(r.value, dev->iaddr + r.reg); + ioread32(dev->iaddr); /* PCI posting */ + + if (r.reg == PHN_CONTROL && !(r.value & PHN_CTL_IRQ)) + phantom_status(dev, dev->status & ~PHB_RUNNING); + spin_unlock_irqrestore(&dev->regs_lock, flags); + break; + case PHN_SETREGS: + case PHN_SET_REGS: + if (copy_from_user(&rs, argp, sizeof(rs))) + return -EFAULT; + + pr_debug("phantom: SRS %u regs %x\n", rs.count, rs.mask); + spin_lock_irqsave(&dev->regs_lock, flags); + if (dev->status & PHB_NOT_OH) + memcpy(&dev->oregs, &rs, sizeof(rs)); + else { + u32 m = min(rs.count, 8U); + for (i = 0; i < m; i++) + if (rs.mask & BIT(i)) + iowrite32(rs.values[i], dev->oaddr + i); + ioread32(dev->iaddr); /* PCI posting */ + } + spin_unlock_irqrestore(&dev->regs_lock, flags); + break; + case PHN_GETREG: + case PHN_GET_REG: + if (copy_from_user(&r, argp, sizeof(r))) + return -EFAULT; + + if (r.reg > 7) + return -EINVAL; + + r.value = ioread32(dev->iaddr + r.reg); + + if (copy_to_user(argp, &r, sizeof(r))) + return -EFAULT; + break; + case PHN_GETREGS: + case PHN_GET_REGS: { + u32 m; + + if (copy_from_user(&rs, argp, sizeof(rs))) + return -EFAULT; + + m = min(rs.count, 8U); + + pr_debug("phantom: GRS %u regs %x\n", rs.count, rs.mask); + spin_lock_irqsave(&dev->regs_lock, flags); + for (i = 0; i < m; i++) + if (rs.mask & BIT(i)) + rs.values[i] = ioread32(dev->iaddr + i); + atomic_set(&dev->counter, 0); + spin_unlock_irqrestore(&dev->regs_lock, flags); + + if (copy_to_user(argp, &rs, sizeof(rs))) + return -EFAULT; + break; + } case PHN_NOT_OH: + spin_lock_irqsave(&dev->regs_lock, flags); + if (dev->status & PHB_RUNNING) { + printk(KERN_ERR "phantom: you need to set NOT_OH " + "before you start the device!\n"); + spin_unlock_irqrestore(&dev->regs_lock, flags); + return -EINVAL; + } + dev->status |= PHB_NOT_OH; + spin_unlock_irqrestore(&dev->regs_lock, flags); + break; + default: + return -ENOTTY; + } + + return 0; +} + +#ifdef CONFIG_COMPAT +static long phantom_compat_ioctl(struct file *filp, unsigned int cmd, + unsigned long arg) +{ + if (_IOC_NR(cmd) <= 3 && _IOC_SIZE(cmd) == sizeof(compat_uptr_t)) { + cmd &= ~(_IOC_SIZEMASK << _IOC_SIZESHIFT); + cmd |= sizeof(void *) << _IOC_SIZESHIFT; + } + return phantom_ioctl(filp, cmd, (unsigned long)compat_ptr(arg)); +} +#else +#define phantom_compat_ioctl NULL +#endif + +static int phantom_open(struct inode *inode, struct file *file) +{ + struct phantom_device *dev = container_of(inode->i_cdev, + struct phantom_device, cdev); + + mutex_lock(&phantom_mutex); + nonseekable_open(inode, file); + + if (mutex_lock_interruptible(&dev->open_lock)) { + mutex_unlock(&phantom_mutex); + return -ERESTARTSYS; + } + + if (dev->opened) { + mutex_unlock(&dev->open_lock); + mutex_unlock(&phantom_mutex); + return -EINVAL; + } + + WARN_ON(dev->status & PHB_NOT_OH); + + file->private_data = dev; + + atomic_set(&dev->counter, 0); + dev->opened++; + mutex_unlock(&dev->open_lock); + mutex_unlock(&phantom_mutex); + return 0; +} + +static int phantom_release(struct inode *inode, struct file *file) +{ + struct phantom_device *dev = file->private_data; + + mutex_lock(&dev->open_lock); + + dev->opened = 0; + phantom_status(dev, dev->status & ~PHB_RUNNING); + dev->status &= ~PHB_NOT_OH; + + mutex_unlock(&dev->open_lock); + + return 0; +} + +static __poll_t phantom_poll(struct file *file, poll_table *wait) +{ + struct phantom_device *dev = file->private_data; + __poll_t mask = 0; + + pr_debug("phantom_poll: %d\n", atomic_read(&dev->counter)); + poll_wait(file, &dev->wait, wait); + + if (!(dev->status & PHB_RUNNING)) + mask = EPOLLERR; + else if (atomic_read(&dev->counter)) + mask = EPOLLIN | EPOLLRDNORM; + + pr_debug("phantom_poll end: %x/%d\n", mask, atomic_read(&dev->counter)); + + return mask; +} + +static const struct file_operations phantom_file_ops = { + .open = phantom_open, + .release = phantom_release, + .unlocked_ioctl = phantom_ioctl, + .compat_ioctl = phantom_compat_ioctl, + .poll = phantom_poll, +}; + +static irqreturn_t phantom_isr(int irq, void *data) +{ + struct phantom_device *dev = data; + unsigned int i; + u32 ctl; + + spin_lock(&dev->regs_lock); + ctl = ioread32(dev->iaddr + PHN_CONTROL); + if (!(ctl & PHN_CTL_IRQ)) { + spin_unlock(&dev->regs_lock); + return IRQ_NONE; + } + + iowrite32(0, dev->iaddr); + iowrite32(0xc0, dev->iaddr); + + if (dev->status & PHB_NOT_OH) { + struct phm_regs *r = &dev->oregs; + u32 m = min(r->count, 8U); + + for (i = 0; i < m; i++) + if (r->mask & BIT(i)) + iowrite32(r->values[i], dev->oaddr + i); + + dev->ctl_reg ^= PHN_CTL_AMP; + iowrite32(dev->ctl_reg, dev->iaddr + PHN_CONTROL); + } + spin_unlock(&dev->regs_lock); + + ioread32(dev->iaddr); /* PCI posting */ + + atomic_inc(&dev->counter); + wake_up_interruptible(&dev->wait); + + return IRQ_HANDLED; +} + +/* + * Init and deinit driver + */ + +static unsigned int phantom_get_free(void) +{ + unsigned int i; + + for (i = 0; i < PHANTOM_MAX_MINORS; i++) + if (phantom_devices[i] == 0) + break; + + return i; +} + +static int phantom_probe(struct pci_dev *pdev, + const struct pci_device_id *pci_id) +{ + struct phantom_device *pht; + unsigned int minor; + int retval; + + retval = pci_enable_device(pdev); + if (retval) { + dev_err(&pdev->dev, "pci_enable_device failed!\n"); + goto err; + } + + minor = phantom_get_free(); + if (minor == PHANTOM_MAX_MINORS) { + dev_err(&pdev->dev, "too many devices found!\n"); + retval = -EIO; + goto err_dis; + } + + phantom_devices[minor] = 1; + + retval = pci_request_regions(pdev, "phantom"); + if (retval) { + dev_err(&pdev->dev, "pci_request_regions failed!\n"); + goto err_null; + } + + retval = -ENOMEM; + pht = kzalloc_obj(*pht); + if (pht == NULL) { + dev_err(&pdev->dev, "unable to allocate device\n"); + goto err_reg; + } + + pht->caddr = pci_iomap(pdev, 0, 0); + if (pht->caddr == NULL) { + dev_err(&pdev->dev, "can't remap conf space\n"); + goto err_fr; + } + pht->iaddr = pci_iomap(pdev, 2, 0); + if (pht->iaddr == NULL) { + dev_err(&pdev->dev, "can't remap input space\n"); + goto err_unmc; + } + pht->oaddr = pci_iomap(pdev, 3, 0); + if (pht->oaddr == NULL) { + dev_err(&pdev->dev, "can't remap output space\n"); + goto err_unmi; + } + + mutex_init(&pht->open_lock); + spin_lock_init(&pht->regs_lock); + init_waitqueue_head(&pht->wait); + cdev_init(&pht->cdev, &phantom_file_ops); + pht->cdev.owner = THIS_MODULE; + + iowrite32(0, pht->caddr + PHN_IRQCTL); + ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */ + retval = request_irq(pdev->irq, phantom_isr, + IRQF_SHARED, "phantom", pht); + if (retval) { + dev_err(&pdev->dev, "can't establish ISR\n"); + goto err_unmo; + } + + retval = cdev_add(&pht->cdev, MKDEV(phantom_major, minor), 1); + if (retval) { + dev_err(&pdev->dev, "chardev registration failed\n"); + goto err_irq; + } + + if (IS_ERR(device_create(&phantom_class, &pdev->dev, + MKDEV(phantom_major, minor), NULL, + "phantom%u", minor))) + dev_err(&pdev->dev, "can't create device\n"); + + pci_set_drvdata(pdev, pht); + + return 0; +err_irq: + free_irq(pdev->irq, pht); +err_unmo: + pci_iounmap(pdev, pht->oaddr); +err_unmi: + pci_iounmap(pdev, pht->iaddr); +err_unmc: + pci_iounmap(pdev, pht->caddr); +err_fr: + kfree(pht); +err_reg: + pci_release_regions(pdev); +err_null: + phantom_devices[minor] = 0; +err_dis: + pci_disable_device(pdev); +err: + return retval; +} + +static void phantom_remove(struct pci_dev *pdev) +{ + struct phantom_device *pht = pci_get_drvdata(pdev); + unsigned int minor = MINOR(pht->cdev.dev); + + device_destroy(&phantom_class, MKDEV(phantom_major, minor)); + + cdev_del(&pht->cdev); + + iowrite32(0, pht->caddr + PHN_IRQCTL); + ioread32(pht->caddr + PHN_IRQCTL); /* PCI posting */ + free_irq(pdev->irq, pht); + + pci_iounmap(pdev, pht->oaddr); + pci_iounmap(pdev, pht->iaddr); + pci_iounmap(pdev, pht->caddr); + + kfree(pht); + + pci_release_regions(pdev); + + phantom_devices[minor] = 0; + + pci_disable_device(pdev); +} + +static int __maybe_unused phantom_suspend(struct device *dev_d) +{ + struct phantom_device *dev = dev_get_drvdata(dev_d); + + iowrite32(0, dev->caddr + PHN_IRQCTL); + ioread32(dev->caddr + PHN_IRQCTL); /* PCI posting */ + + synchronize_irq(to_pci_dev(dev_d)->irq); + + return 0; +} + +static int __maybe_unused phantom_resume(struct device *dev_d) +{ + struct phantom_device *dev = dev_get_drvdata(dev_d); + + iowrite32(0, dev->caddr + PHN_IRQCTL); + + return 0; +} + +static struct pci_device_id phantom_pci_tbl[] = { + { PCI_DEVICE_SUB(PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050, + PCI_VENDOR_ID_PLX, PCI_DEVICE_ID_PLX_9050), + .class = PCI_CLASS_BRIDGE_OTHER << 8, .class_mask = 0xffff00 }, + { } +}; +MODULE_DEVICE_TABLE(pci, phantom_pci_tbl); + +static SIMPLE_DEV_PM_OPS(phantom_pm_ops, phantom_suspend, phantom_resume); + +static struct pci_driver phantom_pci_driver = { + .name = "phantom", + .id_table = phantom_pci_tbl, + .probe = phantom_probe, + .remove = phantom_remove, + .driver.pm = &phantom_pm_ops, +}; + +static CLASS_ATTR_STRING(version, 0444, PHANTOM_VERSION); + +static int __init phantom_init(void) +{ + int retval; + dev_t dev; + + retval = class_register(&phantom_class); + if (retval) { + printk(KERN_ERR "phantom: can't register phantom class\n"); + goto err; + } + retval = class_create_file(&phantom_class, &class_attr_version.attr); + if (retval) { + printk(KERN_ERR "phantom: can't create sysfs version file\n"); + goto err_class; + } + + retval = alloc_chrdev_region(&dev, 0, PHANTOM_MAX_MINORS, "phantom"); + if (retval) { + printk(KERN_ERR "phantom: can't register character device\n"); + goto err_attr; + } + phantom_major = MAJOR(dev); + + retval = pci_register_driver(&phantom_pci_driver); + if (retval) { + printk(KERN_ERR "phantom: can't register pci driver\n"); + goto err_unchr; + } + + printk(KERN_INFO "Phantom Linux Driver, version " PHANTOM_VERSION ", " + "init OK\n"); + + return 0; +err_unchr: + unregister_chrdev_region(dev, PHANTOM_MAX_MINORS); +err_attr: + class_remove_file(&phantom_class, &class_attr_version.attr); +err_class: + class_unregister(&phantom_class); +err: + return retval; +} + +static void __exit phantom_exit(void) +{ + pci_unregister_driver(&phantom_pci_driver); + + unregister_chrdev_region(MKDEV(phantom_major, 0), PHANTOM_MAX_MINORS); + + class_remove_file(&phantom_class, &class_attr_version.attr); + class_unregister(&phantom_class); + + pr_debug("phantom: module successfully removed\n"); +} + +module_init(phantom_init); +module_exit(phantom_exit); + +MODULE_AUTHOR("Jiri Slaby "); +MODULE_DESCRIPTION("Sensable Phantom driver (PCI devices)"); +MODULE_LICENSE("GPL"); +MODULE_VERSION(PHANTOM_VERSION); -- cgit v1.3.1