Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 556 insertions, 0 deletions

diff --git a/drivers/video/fbdev/vfb.c b/drivers/video/fbdev/vfb.c
new file mode 100644
index 000000000..de137b2bd
--- /dev/null
+++ b/drivers/video/fbdev/vfb.c
@@ -0,0 +1,556 @@
+/*
+ *  linux/drivers/video/vfb.c -- Virtual frame buffer device
+ *
+ *      Copyright (C) 2002 James Simmons
+ *
+ *	Copyright (C) 1997 Geert Uytterhoeven
+ *
+ *  This file is subject to the terms and conditions of the GNU General Public
+ *  License. See the file COPYING in the main directory of this archive for
+ *  more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+
+#include <linux/fb.h>
+#include <linux/init.h>
+
+    /*
+     *  RAM we reserve for the frame buffer. This defines the maximum screen
+     *  size
+     *
+     *  The default can be overridden if the driver is compiled as a module
+     */
+
+#define VIDEOMEMSIZE	(1*1024*1024)	/* 1 MB */
+
+static void *videomemory;
+static u_long videomemorysize = VIDEOMEMSIZE;
+module_param(videomemorysize, ulong, 0);
+MODULE_PARM_DESC(videomemorysize, "RAM available to frame buffer (in bytes)");
+
+static char *mode_option = NULL;
+module_param(mode_option, charp, 0);
+MODULE_PARM_DESC(mode_option, "Preferred video mode (e.g. 640x480-8@60)");
+
+static const struct fb_videomode vfb_default = {
+	.xres =		640,
+	.yres =		480,
+	.pixclock =	20000,
+	.left_margin =	64,
+	.right_margin =	64,
+	.upper_margin =	32,
+	.lower_margin =	32,
+	.hsync_len =	64,
+	.vsync_len =	2,
+	.vmode =	FB_VMODE_NONINTERLACED,
+};
+
+static struct fb_fix_screeninfo vfb_fix = {
+	.id =		"Virtual FB",
+	.type =		FB_TYPE_PACKED_PIXELS,
+	.visual =	FB_VISUAL_PSEUDOCOLOR,
+	.xpanstep =	1,
+	.ypanstep =	1,
+	.ywrapstep =	1,
+	.accel =	FB_ACCEL_NONE,
+};
+
+static bool vfb_enable __initdata = 0;	/* disabled by default */
+module_param(vfb_enable, bool, 0);
+MODULE_PARM_DESC(vfb_enable, "Enable Virtual FB driver");
+
+static int vfb_check_var(struct fb_var_screeninfo *var,
+			 struct fb_info *info);
+static int vfb_set_par(struct fb_info *info);
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+			 u_int transp, struct fb_info *info);
+static int vfb_pan_display(struct fb_var_screeninfo *var,
+			   struct fb_info *info);
+static int vfb_mmap(struct fb_info *info,
+		    struct vm_area_struct *vma);
+
+static void vfb_destroy(struct fb_info *info)
+{
+	vfree(info->screen_buffer);
+	fb_dealloc_cmap(&info->cmap);
+	framebuffer_release(info);
+}
+
+static const struct fb_ops vfb_ops = {
+	.owner		= THIS_MODULE,
+	__FB_DEFAULT_SYSMEM_OPS_RDWR,
+	.fb_check_var	= vfb_check_var,
+	.fb_set_par	= vfb_set_par,
+	.fb_setcolreg	= vfb_setcolreg,
+	.fb_pan_display	= vfb_pan_display,
+	__FB_DEFAULT_SYSMEM_OPS_DRAW,
+	.fb_mmap	= vfb_mmap,
+	.fb_destroy	= vfb_destroy,
+};
+
+    /*
+     *  Internal routines
+     */
+
+static u_long get_line_length(int xres_virtual, int bpp)
+{
+	u_long length;
+
+	length = xres_virtual * bpp;
+	length = (length + 31) & ~31;
+	length >>= 3;
+	return (length);
+}
+
+    /*
+     *  Setting the video mode has been split into two parts.
+     *  First part, xxxfb_check_var, must not write anything
+     *  to hardware, it should only verify and adjust var.
+     *  This means it doesn't alter par but it does use hardware
+     *  data from it to check this var.
+     */
+
+static int vfb_check_var(struct fb_var_screeninfo *var,
+			 struct fb_info *info)
+{
+	u_long line_length;
+
+	/*
+	 *  FB_VMODE_CONUPDATE and FB_VMODE_SMOOTH_XPAN are equal!
+	 *  as FB_VMODE_SMOOTH_XPAN is only used internally
+	 */
+
+	if (var->vmode & FB_VMODE_CONUPDATE) {
+		var->vmode |= FB_VMODE_YWRAP;
+		var->xoffset = info->var.xoffset;
+		var->yoffset = info->var.yoffset;
+	}
+
+	/*
+	 *  Some very basic checks
+	 */
+	if (!var->xres)
+		var->xres = 1;
+	if (!var->yres)
+		var->yres = 1;
+	if (var->xres > var->xres_virtual)
+		var->xres_virtual = var->xres;
+	if (var->yres > var->yres_virtual)
+		var->yres_virtual = var->yres;
+	if (var->bits_per_pixel <= 1)
+		var->bits_per_pixel = 1;
+	else if (var->bits_per_pixel <= 8)
+		var->bits_per_pixel = 8;
+	else if (var->bits_per_pixel <= 16)
+		var->bits_per_pixel = 16;
+	else if (var->bits_per_pixel <= 24)
+		var->bits_per_pixel = 24;
+	else if (var->bits_per_pixel <= 32)
+		var->bits_per_pixel = 32;
+	else
+		return -EINVAL;
+
+	if (var->xres_virtual < var->xoffset + var->xres)
+		var->xres_virtual = var->xoffset + var->xres;
+	if (var->yres_virtual < var->yoffset + var->yres)
+		var->yres_virtual = var->yoffset + var->yres;
+
+	/*
+	 *  Memory limit
+	 */
+	line_length =
+	    get_line_length(var->xres_virtual, var->bits_per_pixel);
+	if (line_length * var->yres_virtual > videomemorysize)
+		return -ENOMEM;
+
+	/*
+	 * Now that we checked it we alter var. The reason being is that the video
+	 * mode passed in might not work but slight changes to it might make it
+	 * work. This way we let the user know what is acceptable.
+	 */
+	switch (var->bits_per_pixel) {
+	case 1:
+	case 8:
+		var->red.offset = 0;
+		var->red.length = 8;
+		var->green.offset = 0;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		break;
+	case 16:		/* RGBA 5551 */
+		if (var->transp.length) {
+			var->red.offset = 0;
+			var->red.length = 5;
+			var->green.offset = 5;
+			var->green.length = 5;
+			var->blue.offset = 10;
+			var->blue.length = 5;
+			var->transp.offset = 15;
+			var->transp.length = 1;
+		} else {	/* RGB 565 */
+			var->red.offset = 0;
+			var->red.length = 5;
+			var->green.offset = 5;
+			var->green.length = 6;
+			var->blue.offset = 11;
+			var->blue.length = 5;
+			var->transp.offset = 0;
+			var->transp.length = 0;
+		}
+		break;
+	case 24:		/* RGB 888 */
+		var->red.offset = 0;
+		var->red.length = 8;
+		var->green.offset = 8;
+		var->green.length = 8;
+		var->blue.offset = 16;
+		var->blue.length = 8;
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		break;
+	case 32:		/* RGBA 8888 */
+		var->red.offset = 0;
+		var->red.length = 8;
+		var->green.offset = 8;
+		var->green.length = 8;
+		var->blue.offset = 16;
+		var->blue.length = 8;
+		var->transp.offset = 24;
+		var->transp.length = 8;
+		break;
+	}
+	var->red.msb_right = 0;
+	var->green.msb_right = 0;
+	var->blue.msb_right = 0;
+	var->transp.msb_right = 0;
+
+	return 0;
+}
+
+/* This routine actually sets the video mode. It's in here where we
+ * the hardware state info->par and fix which can be affected by the
+ * change in par. For this driver it doesn't do much.
+ */
+static int vfb_set_par(struct fb_info *info)
+{
+	switch (info->var.bits_per_pixel) {
+	case 1:
+		info->fix.visual = FB_VISUAL_MONO01;
+		break;
+	case 8:
+		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+		break;
+	case 16:
+	case 24:
+	case 32:
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		break;
+	}
+
+	info->fix.line_length = get_line_length(info->var.xres_virtual,
+						info->var.bits_per_pixel);
+
+	return 0;
+}
+
+    /*
+     *  Set a single color register. The values supplied are already
+     *  rounded down to the hardware's capabilities (according to the
+     *  entries in the var structure). Return != 0 for invalid regno.
+     */
+
+static int vfb_setcolreg(u_int regno, u_int red, u_int green, u_int blue,
+			 u_int transp, struct fb_info *info)
+{
+	if (regno >= 256)	/* no. of hw registers */
+		return 1;
+	/*
+	 * Program hardware... do anything you want with transp
+	 */
+
+	/* grayscale works only partially under directcolor */
+	if (info->var.grayscale) {
+		/* grayscale = 0.30*R + 0.59*G + 0.11*B */
+		red = green = blue =
+		    (red * 77 + green * 151 + blue * 28) >> 8;
+	}
+
+	/* Directcolor:
+	 *   var->{color}.offset contains start of bitfield
+	 *   var->{color}.length contains length of bitfield
+	 *   {hardwarespecific} contains width of RAMDAC
+	 *   cmap[X] is programmed to (X << red.offset) | (X << green.offset) | (X << blue.offset)
+	 *   RAMDAC[X] is programmed to (red, green, blue)
+	 *
+	 * Pseudocolor:
+	 *    var->{color}.offset is 0 unless the palette index takes less than
+	 *                        bits_per_pixel bits and is stored in the upper
+	 *                        bits of the pixel value
+	 *    var->{color}.length is set so that 1 << length is the number of available
+	 *                        palette entries
+	 *    cmap is not used
+	 *    RAMDAC[X] is programmed to (red, green, blue)
+	 *
+	 * Truecolor:
+	 *    does not use DAC. Usually 3 are present.
+	 *    var->{color}.offset contains start of bitfield
+	 *    var->{color}.length contains length of bitfield
+	 *    cmap is programmed to (red << red.offset) | (green << green.offset) |
+	 *                      (blue << blue.offset) | (transp << transp.offset)
+	 *    RAMDAC does not exist
+	 */
+#define CNVT_TOHW(val,width) ((((val)<<(width))+0x7FFF-(val))>>16)
+	switch (info->fix.visual) {
+	case FB_VISUAL_TRUECOLOR:
+	case FB_VISUAL_PSEUDOCOLOR:
+		red = CNVT_TOHW(red, info->var.red.length);
+		green = CNVT_TOHW(green, info->var.green.length);
+		blue = CNVT_TOHW(blue, info->var.blue.length);
+		transp = CNVT_TOHW(transp, info->var.transp.length);
+		break;
+	case FB_VISUAL_DIRECTCOLOR:
+		red = CNVT_TOHW(red, 8);	/* expect 8 bit DAC */
+		green = CNVT_TOHW(green, 8);
+		blue = CNVT_TOHW(blue, 8);
+		/* hey, there is bug in transp handling... */
+		transp = CNVT_TOHW(transp, 8);
+		break;
+	}
+#undef CNVT_TOHW
+	/* Truecolor has hardware independent palette */
+	if (info->fix.visual == FB_VISUAL_TRUECOLOR) {
+		u32 v;
+
+		if (regno >= 16)
+			return 1;
+
+		v = (red << info->var.red.offset) |
+		    (green << info->var.green.offset) |
+		    (blue << info->var.blue.offset) |
+		    (transp << info->var.transp.offset);
+		switch (info->var.bits_per_pixel) {
+		case 8:
+			break;
+		case 16:
+			((u32 *) (info->pseudo_palette))[regno] = v;
+			break;
+		case 24:
+		case 32:
+			((u32 *) (info->pseudo_palette))[regno] = v;
+			break;
+		}
+		return 0;
+	}
+	return 0;
+}
+
+    /*
+     *  Pan or Wrap the Display
+     *
+     *  This call looks only at xoffset, yoffset and the FB_VMODE_YWRAP flag
+     */
+
+static int vfb_pan_display(struct fb_var_screeninfo *var,
+			   struct fb_info *info)
+{
+	if (var->vmode & FB_VMODE_YWRAP) {
+		if (var->yoffset >= info->var.yres_virtual ||
+		    var->xoffset)
+			return -EINVAL;
+	} else {
+		if (var->xoffset + info->var.xres > info->var.xres_virtual ||
+		    var->yoffset + info->var.yres > info->var.yres_virtual)
+			return -EINVAL;
+	}
+	info->var.xoffset = var->xoffset;
+	info->var.yoffset = var->yoffset;
+	if (var->vmode & FB_VMODE_YWRAP)
+		info->var.vmode |= FB_VMODE_YWRAP;
+	else
+		info->var.vmode &= ~FB_VMODE_YWRAP;
+	return 0;
+}
+
+    /*
+     *  Most drivers don't need their own mmap function
+     */
+
+static int vfb_mmap(struct fb_info *info,
+		    struct vm_area_struct *vma)
+{
+	vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot);
+
+	return remap_vmalloc_range(vma, (void *)info->fix.smem_start, vma->vm_pgoff);
+}
+
+#ifndef MODULE
+/*
+ * The virtual framebuffer driver is only enabled if explicitly
+ * requested by passing 'video=vfb:' (or any actual options).
+ */
+static int __init vfb_setup(char *options)
+{
+	char *this_opt;
+
+	vfb_enable = 0;
+
+	if (!options)
+		return 1;
+
+	vfb_enable = 1;
+
+	if (!*options)
+		return 1;
+
+	while ((this_opt = strsep(&options, ",")) != NULL) {
+		if (!*this_opt)
+			continue;
+		/* Test disable for backwards compatibility */
+		if (!strcmp(this_opt, "disable"))
+			vfb_enable = 0;
+		else
+			mode_option = this_opt;
+	}
+	return 1;
+}
+#endif  /*  MODULE  */
+
+    /*
+     *  Initialisation
+     */
+
+static int vfb_probe(struct platform_device *dev)
+{
+	struct fb_info *info;
+	unsigned int size = PAGE_ALIGN(videomemorysize);
+	int retval = -ENOMEM;
+
+	/*
+	 * For real video cards we use ioremap.
+	 */
+	if (!(videomemory = vmalloc_32_user(size)))
+		return retval;
+
+	info = framebuffer_alloc(sizeof(u32) * 256, &dev->dev);
+	if (!info)
+		goto err;
+
+	info->flags |= FBINFO_VIRTFB;
+	info->screen_buffer = videomemory;
+	info->fbops = &vfb_ops;
+
+	if (!fb_find_mode(&info->var, info, mode_option,
+			  NULL, 0, &vfb_default, 8)){
+		fb_err(info, "Unable to find usable video mode.\n");
+		retval = -EINVAL;
+		goto err1;
+	}
+
+	vfb_fix.smem_start = (unsigned long) videomemory;
+	vfb_fix.smem_len = videomemorysize;
+	info->fix = vfb_fix;
+	info->pseudo_palette = info->par;
+	info->par = NULL;
+
+	retval = fb_alloc_cmap(&info->cmap, 256, 0);
+	if (retval < 0)
+		goto err1;
+
+	retval = register_framebuffer(info);
+	if (retval < 0)
+		goto err2;
+	platform_set_drvdata(dev, info);
+
+	vfb_set_par(info);
+
+	fb_info(info, "Virtual frame buffer device, using %ldK of video memory\n",
+		videomemorysize >> 10);
+	return 0;
+err2:
+	fb_dealloc_cmap(&info->cmap);
+err1:
+	framebuffer_release(info);
+err:
+	vfree(videomemory);
+	return retval;
+}
+
+static void vfb_remove(struct platform_device *dev)
+{
+	struct fb_info *info = platform_get_drvdata(dev);
+
+	if (info) {
+		unregister_framebuffer(info);
+	}
+}
+
+static struct platform_driver vfb_driver = {
+	.probe	= vfb_probe,
+	.remove = vfb_remove,
+	.driver = {
+		.name	= "vfb",
+	},
+};
+
+static struct platform_device *vfb_device;
+
+static int __init vfb_init(void)
+{
+	int ret = 0;
+
+#ifndef MODULE
+	char *option = NULL;
+
+	if (fb_get_options("vfb", &option))
+		return -ENODEV;
+	vfb_setup(option);
+#endif
+
+	if (!vfb_enable)
+		return -ENXIO;
+
+	ret = platform_driver_register(&vfb_driver);
+
+	if (!ret) {
+		vfb_device = platform_device_alloc("vfb", 0);
+
+		if (vfb_device)
+			ret = platform_device_add(vfb_device);
+		else
+			ret = -ENOMEM;
+
+		if (ret) {
+			platform_device_put(vfb_device);
+			platform_driver_unregister(&vfb_driver);
+		}
+	}
+
+	return ret;
+}
+
+module_init(vfb_init);
+
+#ifdef MODULE
+static void __exit vfb_exit(void)
+{
+	platform_device_unregister(vfb_device);
+	platform_driver_unregister(&vfb_driver);
+}
+
+module_exit(vfb_exit);
+
+MODULE_DESCRIPTION("Virtual Frame Buffer driver");
+MODULE_LICENSE("GPL");
+#endif				/* MODULE */