cregit-Linux how code gets into the kernel

Release 4.7 drivers/misc/mei/main.c

Directory: drivers/misc/mei
/*
 *
 * Intel Management Engine Interface (Intel MEI) Linux driver
 * Copyright (c) 2003-2012, Intel Corporation.
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 */
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/ioctl.h>
#include <linux/cdev.h>
#include <linux/sched.h>
#include <linux/uuid.h>
#include <linux/compat.h>
#include <linux/jiffies.h>
#include <linux/interrupt.h>

#include <linux/mei.h>

#include "mei_dev.h"
#include "client.h"

/**
 * mei_open - the open function
 *
 * @inode: pointer to inode structure
 * @file: pointer to file structure
 *
 * Return: 0 on success, <0 on error
 */

static int mei_open(struct inode *inode, struct file *file) { struct mei_device *dev; struct mei_cl *cl; int err; dev = container_of(inode->i_cdev, struct mei_device, cdev); if (!dev) return -ENODEV; mutex_lock(&dev->device_lock); if (dev->dev_state != MEI_DEV_ENABLED) { dev_dbg(dev->dev, "dev_state != MEI_ENABLED dev_state = %s\n", mei_dev_state_str(dev->dev_state)); err = -ENODEV; goto err_unlock; } cl = mei_cl_alloc_linked(dev); if (IS_ERR(cl)) { err = PTR_ERR(cl); goto err_unlock; } file->private_data = cl; mutex_unlock(&dev->device_lock); return nonseekable_open(inode, file); err_unlock: mutex_unlock(&dev->device_lock); return err; }

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oren weiloren weil9863.23%220.00%
tomas winklertomas winkler5032.26%770.00%
alexander usyskinalexander usyskin74.52%110.00%
Total155100.00%10100.00%

/** * mei_release - the release function * * @inode: pointer to inode structure * @file: pointer to file structure * * Return: 0 on success, <0 on error */
static int mei_release(struct inode *inode, struct file *file) { struct mei_cl *cl = file->private_data; struct mei_device *dev; int rets; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; dev = cl->dev; mutex_lock(&dev->device_lock); if (cl == &dev->iamthif_cl) { rets = mei_amthif_release(dev, file); goto out; } rets = mei_cl_disconnect(cl); mei_cl_flush_queues(cl, file); cl_dbg(dev, cl, "removing\n"); mei_cl_unlink(cl); file->private_data = NULL; kfree(cl); out: mutex_unlock(&dev->device_lock); return rets; }

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oren weiloren weil11784.17%233.33%
tomas winklertomas winkler2215.83%466.67%
Total139100.00%6100.00%

/** * mei_read - the read function. * * @file: pointer to file structure * @ubuf: pointer to user buffer * @length: buffer length * @offset: data offset in buffer * * Return: >=0 data length on success , <0 on error */
static ssize_t mei_read(struct file *file, char __user *ubuf, size_t length, loff_t *offset) { struct mei_cl *cl = file->private_data; struct mei_device *dev; struct mei_cl_cb *cb = NULL; int rets; int err; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; dev = cl->dev; mutex_lock(&dev->device_lock); if (dev->dev_state != MEI_DEV_ENABLED) { rets = -ENODEV; goto out; } if (length == 0) { rets = 0; goto out; } if (ubuf == NULL) { rets = -EMSGSIZE; goto out; } if (cl == &dev->iamthif_cl) { rets = mei_amthif_read(dev, file, ubuf, length, offset); goto out; } cb = mei_cl_read_cb(cl, file); if (cb) goto copy_buffer; if (*offset > 0) *offset = 0; err = mei_cl_read_start(cl, length, file); if (err && err != -EBUSY) { cl_dbg(dev, cl, "mei start read failure status = %d\n", err); rets = err; goto out; } if (list_empty(&cl->rd_completed) && !waitqueue_active(&cl->rx_wait)) { if (file->f_flags & O_NONBLOCK) { rets = -EAGAIN; goto out; } mutex_unlock(&dev->device_lock); if (wait_event_interruptible(cl->rx_wait, (!list_empty(&cl->rd_completed)) || (!mei_cl_is_connected(cl)))) { if (signal_pending(current)) return -EINTR; return -ERESTARTSYS; } mutex_lock(&dev->device_lock); if (!mei_cl_is_connected(cl)) { rets = -EBUSY; goto out; } } cb = mei_cl_read_cb(cl, file); if (!cb) { rets = 0; goto out; } copy_buffer: /* now copy the data to user space */ if (cb->status) { rets = cb->status; cl_dbg(dev, cl, "read operation failed %d\n", rets); goto free; } cl_dbg(dev, cl, "buf.size = %zu buf.idx = %zu offset = %lld\n", cb->buf.size, cb->buf_idx, *offset); if (*offset >= cb->buf_idx) { rets = 0; goto free; } /* length is being truncated to PAGE_SIZE, * however buf_idx may point beyond that */ length = min_t(size_t, length, cb->buf_idx - *offset); if (copy_to_user(ubuf, cb->buf.data + *offset, length)) { dev_dbg(dev->dev, "failed to copy data to userland\n"); rets = -EFAULT; goto free; } rets = length; *offset += length; /* not all data was read, keep the cb */ if (*offset < cb->buf_idx) goto out; free: mei_io_cb_free(cb); *offset = 0; out: cl_dbg(dev, cl, "end mei read rets = %d\n", rets); mutex_unlock(&dev->device_lock); return rets; }

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oren weiloren weil41274.77%29.52%
tomas winklertomas winkler8916.15%1571.43%
alexander usyskinalexander usyskin509.07%419.05%
Total551100.00%21100.00%

/** * mei_write - the write function. * * @file: pointer to file structure * @ubuf: pointer to user buffer * @length: buffer length * @offset: data offset in buffer * * Return: >=0 data length on success , <0 on error */
static ssize_t mei_write(struct file *file, const char __user *ubuf, size_t length, loff_t *offset) { struct mei_cl *cl = file->private_data; struct mei_cl_cb *cb; struct mei_device *dev; int rets; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; dev = cl->dev; mutex_lock(&dev->device_lock); if (dev->dev_state != MEI_DEV_ENABLED) { rets = -ENODEV; goto out; } if (!mei_cl_is_connected(cl)) { cl_err(dev, cl, "is not connected"); rets = -ENODEV; goto out; } if (!mei_me_cl_is_active(cl->me_cl)) { rets = -ENOTTY; goto out; } if (length > mei_cl_mtu(cl)) { rets = -EFBIG; goto out; } if (length == 0) { rets = 0; goto out; } *offset = 0; cb = mei_cl_alloc_cb(cl, length, MEI_FOP_WRITE, file); if (!cb) { rets = -ENOMEM; goto out; } rets = copy_from_user(cb->buf.data, ubuf, length); if (rets) { dev_dbg(dev->dev, "failed to copy data from userland\n"); rets = -EFAULT; mei_io_cb_free(cb); goto out; } if (cl == &dev->iamthif_cl) { rets = mei_amthif_write(cl, cb); if (!rets) rets = length; goto out; } rets = mei_cl_write(cl, cb, false); out: mutex_unlock(&dev->device_lock); return rets; }

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oren weiloren weil16553.57%212.50%
tomas winklertomas winkler8427.27%1062.50%
alexander usyskinalexander usyskin5919.16%425.00%
Total308100.00%16100.00%

/** * mei_ioctl_connect_client - the connect to fw client IOCTL function * * @file: private data of the file object * @data: IOCTL connect data, input and output parameters * * Locking: called under "dev->device_lock" lock * * Return: 0 on success, <0 on failure. */
static int mei_ioctl_connect_client(struct file *file, struct mei_connect_client_data *data) { struct mei_device *dev; struct mei_client *client; struct mei_me_client *me_cl; struct mei_cl *cl; int rets; cl = file->private_data; dev = cl->dev; if (dev->dev_state != MEI_DEV_ENABLED) return -ENODEV; if (cl->state != MEI_FILE_INITIALIZING && cl->state != MEI_FILE_DISCONNECTED) return -EBUSY; /* find ME client we're trying to connect to */ me_cl = mei_me_cl_by_uuid(dev, &data->in_client_uuid); if (!me_cl) { dev_dbg(dev->dev, "Cannot connect to FW Client UUID = %pUl\n", &data->in_client_uuid); rets = -ENOTTY; goto end; } if (me_cl->props.fixed_address) { bool forbidden = dev->override_fixed_address ? !dev->allow_fixed_address : !dev->hbm_f_fa_supported; if (forbidden) { dev_dbg(dev->dev, "Connection forbidden to FW Client UUID = %pUl\n", &data->in_client_uuid); rets = -ENOTTY; goto end; } } dev_dbg(dev->dev, "Connect to FW Client ID = %d\n", me_cl->client_id); dev_dbg(dev->dev, "FW Client - Protocol Version = %d\n", me_cl->props.protocol_version); dev_dbg(dev->dev, "FW Client - Max Msg Len = %d\n", me_cl->props.max_msg_length); /* if we're connecting to amthif client then we will use the * existing connection */ if (uuid_le_cmp(data->in_client_uuid, mei_amthif_guid) == 0) { dev_dbg(dev->dev, "FW Client is amthi\n"); if (!mei_cl_is_connected(&dev->iamthif_cl)) { rets = -ENODEV; goto end; } mei_cl_unlink(cl); kfree(cl); cl = NULL; dev->iamthif_open_count++; file->private_data = &dev->iamthif_cl; client = &data->out_client_properties; client->max_msg_length = me_cl->props.max_msg_length; client->protocol_version = me_cl->props.protocol_version; rets = dev->iamthif_cl.status; goto end; } /* prepare the output buffer */ client = &data->out_client_properties; client->max_msg_length = me_cl->props.max_msg_length; client->protocol_version = me_cl->props.protocol_version; dev_dbg(dev->dev, "Can connect?\n"); rets = mei_cl_connect(cl, me_cl, file); end: mei_me_cl_put(me_cl); return rets; }

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tomas winklertomas winkler32984.14%763.64%
alexander usyskinalexander usyskin6215.86%436.36%
Total391100.00%11100.00%

/** * mei_ioctl_client_notify_request - * propagate event notification request to client * * @file: pointer to file structure * @request: 0 - disable, 1 - enable * * Return: 0 on success , <0 on error */
static int mei_ioctl_client_notify_request(const struct file *file, u32 request) { struct mei_cl *cl = file->private_data; if (request != MEI_HBM_NOTIFICATION_START && request != MEI_HBM_NOTIFICATION_STOP) return -EINVAL; return mei_cl_notify_request(cl, file, (u8)request); }

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tomas winklertomas winkler3466.67%266.67%
alexander usyskinalexander usyskin1733.33%133.33%
Total51100.00%3100.00%

/** * mei_ioctl_client_notify_get - wait for notification request * * @file: pointer to file structure * @notify_get: 0 - disable, 1 - enable * * Return: 0 on success , <0 on error */
static int mei_ioctl_client_notify_get(const struct file *file, u32 *notify_get) { struct mei_cl *cl = file->private_data; bool notify_ev; bool block = (file->f_flags & O_NONBLOCK) == 0; int rets; rets = mei_cl_notify_get(cl, block, &notify_ev); if (rets) return rets; *notify_get = notify_ev ? 1 : 0; return 0; }

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tomas winklertomas winkler75100.00%2100.00%
Total75100.00%2100.00%

/** * mei_ioctl - the IOCTL function * * @file: pointer to file structure * @cmd: ioctl command * @data: pointer to mei message structure * * Return: 0 on success , <0 on error */
static long mei_ioctl(struct file *file, unsigned int cmd, unsigned long data) { struct mei_device *dev; struct mei_cl *cl = file->private_data; struct mei_connect_client_data connect_data; u32 notify_get, notify_req; int rets; if (WARN_ON(!cl || !cl->dev)) return -ENODEV; dev = cl->dev; dev_dbg(dev->dev, "IOCTL cmd = 0x%x", cmd); mutex_lock(&dev->device_lock); if (dev->dev_state != MEI_DEV_ENABLED) { rets = -ENODEV; goto out; } switch (cmd) { case IOCTL_MEI_CONNECT_CLIENT: dev_dbg(dev->dev, ": IOCTL_MEI_CONNECT_CLIENT.\n"); if (copy_from_user(&connect_data, (char __user *)data, sizeof(struct mei_connect_client_data))) { dev_dbg(dev->dev, "failed to copy data from userland\n"); rets = -EFAULT; goto out; } rets = mei_ioctl_connect_client(file, &connect_data); if (rets) goto out; /* if all is ok, copying the data back to user. */ if (copy_to_user((char __user *)data, &connect_data, sizeof(struct mei_connect_client_data))) { dev_dbg(dev->dev, "failed to copy data to userland\n"); rets = -EFAULT; goto out; } break; case IOCTL_MEI_NOTIFY_SET: dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_SET.\n"); if (copy_from_user(&notify_req, (char __user *)data, sizeof(notify_req))) { dev_dbg(dev->dev, "failed to copy data from userland\n"); rets = -EFAULT; goto out; } rets = mei_ioctl_client_notify_request(file, notify_req); break; case IOCTL_MEI_NOTIFY_GET: dev_dbg(dev->dev, ": IOCTL_MEI_NOTIFY_GET.\n"); rets = mei_ioctl_client_notify_get(file, &notify_get); if (rets) goto out; dev_dbg(dev->dev, "copy connect data to user\n"); if (copy_to_user((char __user *)data, &notify_get, sizeof(notify_get))) { dev_dbg(dev->dev, "failed to copy data to userland\n"); rets = -EFAULT; goto out; } break; default: dev_err(dev->dev, ": unsupported ioctl %d.\n", cmd); rets = -ENOIOCTLCMD; } out: mutex_unlock(&dev->device_lock); return rets; }

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oren weiloren weil21354.48%228.57%
tomas winklertomas winkler17745.27%457.14%
alexander usyskinalexander usyskin10.26%114.29%
Total391100.00%7100.00%

/** * mei_compat_ioctl - the compat IOCTL function * * @file: pointer to file structure * @cmd: ioctl command * @data: pointer to mei message structure * * Return: 0 on success , <0 on error */ #ifdef CONFIG_COMPAT
static long mei_compat_ioctl(struct file *file, unsigned int cmd, unsigned long data) { return mei_ioctl(file, cmd, (unsigned long)compat_ptr(data)); }

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oren weiloren weil36100.00%2100.00%
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#endif /** * mei_poll - the poll function * * @file: pointer to file structure * @wait: pointer to poll_table structure * * Return: poll mask */
static unsigned int mei_poll(struct file *file, poll_table *wait) { unsigned long req_events = poll_requested_events(wait); struct mei_cl *cl = file->private_data; struct mei_device *dev; unsigned int mask = 0; bool notify_en; if (WARN_ON(!cl || !cl->dev)) return POLLERR; dev = cl->dev; mutex_lock(&dev->device_lock); notify_en = cl->notify_en && (req_events & POLLPRI); if (dev->dev_state != MEI_DEV_ENABLED || !mei_cl_is_connected(cl)) { mask = POLLERR; goto out; } if (cl == &dev->iamthif_cl) { mask = mei_amthif_poll(dev, file, wait); goto out; } if (notify_en) { poll_wait(file, &cl->ev_wait, wait); if (cl->notify_ev) mask |= POLLPRI; } if (req_events & (POLLIN | POLLRDNORM)) { poll_wait(file, &cl->rx_wait, wait); if (!list_empty(&cl->rd_completed)) mask |= POLLIN | POLLRDNORM; else mei_cl_read_start(cl, 0, file); } out: mutex_unlock(&dev->device_lock); return mask; }

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oren weiloren weil11851.30%228.57%
tomas winklertomas winkler11248.70%571.43%
Total230100.00%7100.00%

/** * mei_fasync - asynchronous io support * * @fd: file descriptor * @file: pointer to file structure * @band: band bitmap * * Return: negative on error, * 0 if it did no changes, * and positive a process was added or deleted */
static int mei_fasync(int fd, struct file *file, int band) { struct mei_cl *cl = file->private_data; if (!mei_cl_is_connected(cl)) return -ENODEV; return fasync_helper(fd, file, band, &cl->ev_async); }

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tomas winklertomas winkler53100.00%2100.00%
Total53100.00%2100.00%

/** * fw_status_show - mei device attribute show method * * @device: device pointer * @attr: attribute pointer * @buf: char out buffer * * Return: number of the bytes printed into buf or error */
static ssize_t fw_status_show(struct device *device, struct device_attribute *attr, char *buf) { struct mei_device *dev = dev_get_drvdata(device); struct mei_fw_status fw_status; int err, i; ssize_t cnt = 0; mutex_lock(&dev->device_lock); err = mei_fw_status(dev, &fw_status); mutex_unlock(&dev->device_lock); if (err) { dev_err(device, "read fw_status error = %d\n", err); return err; } for (i = 0; i < fw_status.count; i++) cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n", fw_status.status[i]); return cnt; }

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tomas winklertomas winkler128100.00%1100.00%
Total128100.00%1100.00%

static DEVICE_ATTR_RO(fw_status); static struct attribute *mei_attrs[] = { &dev_attr_fw_status.attr, NULL }; ATTRIBUTE_GROUPS(mei); /* * file operations structure will be used for mei char device. */ static const struct file_operations mei_fops = { .owner = THIS_MODULE, .read = mei_read, .unlocked_ioctl = mei_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = mei_compat_ioctl, #endif .open = mei_open, .release = mei_release, .write = mei_write, .poll = mei_poll, .fasync = mei_fasync, .llseek = no_llseek }; static struct class *mei_class; static dev_t mei_devt; #define MEI_MAX_DEVS MINORMASK static DEFINE_MUTEX(mei_minor_lock); static DEFINE_IDR(mei_idr); /** * mei_minor_get - obtain next free device minor number * * @dev: device pointer * * Return: allocated minor, or -ENOSPC if no free minor left */
static int mei_minor_get(struct mei_device *dev) { int ret; mutex_lock(&mei_minor_lock); ret = idr_alloc(&mei_idr, dev, 0, MEI_MAX_DEVS, GFP_KERNEL); if (ret >= 0) dev->minor = ret; else if (ret == -ENOSPC) dev_err(dev->dev, "too many mei devices\n"); mutex_unlock(&mei_minor_lock); return ret; }

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alexander usyskinalexander usyskin6790.54%150.00%
oren weiloren weil79.46%150.00%
Total74100.00%2100.00%

/** * mei_minor_free - mark device minor number as free * * @dev: device pointer */
static void mei_minor_free(struct mei_device *dev) { mutex_lock(&mei_minor_lock); idr_remove(&mei_idr, dev->minor); mutex_unlock(&mei_minor_lock); }

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alexander usyskinalexander usyskin33100.00%1100.00%
Total33100.00%1100.00%


int mei_register(struct mei_device *dev, struct device *parent) { struct device *clsdev; /* class device */ int ret, devno; ret = mei_minor_get(dev); if (ret < 0) return ret; /* Fill in the data structures */ devno = MKDEV(MAJOR(mei_devt), dev->minor); cdev_init(&dev->cdev, &mei_fops); dev->cdev.owner = parent->driver->owner; /* Add the device */ ret = cdev_add(&dev->cdev, devno, 1); if (ret) { dev_err(parent, "unable to add device %d:%d\n", MAJOR(mei_devt), dev->minor); goto err_dev_add; } clsdev = device_create_with_groups(mei_class, parent, devno, dev, mei_groups, "mei%d", dev->minor); if (IS_ERR(clsdev)) { dev_err(parent, "unable to create device %d:%d\n", MAJOR(mei_devt), dev->minor); ret = PTR_ERR(clsdev); goto err_dev_create; } ret = mei_dbgfs_register(dev, dev_name(clsdev)); if (ret) { dev_err(clsdev, "cannot register debugfs ret = %d\n", ret); goto err_dev_dbgfs; } return 0; err_dev_dbgfs: device_destroy(mei_class, devno); err_dev_create: cdev_del(&dev->cdev); err_dev_add: mei_minor_free(dev); return ret; }

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alexander usyskinalexander usyskin18376.89%112.50%
tomas winklertomas winkler4217.65%562.50%
oren weiloren weil135.46%225.00%
Total238100.00%8100.00%

EXPORT_SYMBOL_GPL(mei_register);
void mei_deregister(struct mei_device *dev) { int devno; devno = dev->cdev.dev; cdev_del(&dev->cdev); mei_dbgfs_deregister(dev); device_destroy(mei_class, devno); mei_minor_free(dev); }

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alexander usyskinalexander usyskin2758.70%120.00%
tomas winklertomas winkler1532.61%240.00%
oren weiloren weil48.70%240.00%
Total46100.00%5100.00%

EXPORT_SYMBOL_GPL(mei_deregister);
static int __init mei_init(void) { int ret; mei_class = class_create(THIS_MODULE, "mei"); if (IS_ERR(mei_class)) { pr_err("couldn't create class\n"); ret = PTR_ERR(mei_class); goto err; } ret = alloc_chrdev_region(&mei_devt, 0, MEI_MAX_DEVS, "mei"); if (ret < 0) { pr_err("unable to allocate char dev region\n"); goto err_class; } ret = mei_cl_bus_init(); if (ret < 0) { pr_err("unable to initialize bus\n"); goto err_chrdev; } return 0; err_chrdev: unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); err_class: class_destroy(mei_class); err: return ret; }

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alexander usyskinalexander usyskin10890.00%150.00%
samuel ortizsamuel ortiz1210.00%150.00%
Total120100.00%2100.00%


static void __exit mei_exit(void) { unregister_chrdev_region(mei_devt, MEI_MAX_DEVS); class_destroy(mei_class); mei_cl_bus_exit(); }

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alexander usyskinalexander usyskin1250.00%150.00%
samuel ortizsamuel ortiz1250.00%150.00%
Total24100.00%2100.00%

module_init(mei_init); module_exit(mei_exit); MODULE_AUTHOR("Intel Corporation"); MODULE_DESCRIPTION("Intel(R) Management Engine Interface"); MODULE_LICENSE("GPL v2");

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oren weiloren weil130439.78%22.86%
tomas winklertomas winkler127838.99%5477.14%
alexander usyskinalexander usyskin66220.20%1318.57%
samuel ortizsamuel ortiz341.04%11.43%
Total3278100.00%70100.00%
Directory: drivers/misc/mei
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