Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

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

1 files changed, 428 insertions, 0 deletions

diff --git a/drivers/video/fbdev/ocfb.c b/drivers/video/fbdev/ocfb.c
new file mode 100644
index 000000000..893888260
--- /dev/null
+++ b/drivers/video/fbdev/ocfb.c
@@ -0,0 +1,428 @@
+/*
+ * OpenCores VGA/LCD 2.0 core frame buffer driver
+ *
+ * Copyright (C) 2013 Stefan Kristiansson, stefan.kristiansson@saunalahti.fi
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/string.h>
+#include <linux/slab.h>
+
+/* OCFB register defines */
+#define OCFB_CTRL	0x000
+#define OCFB_STAT	0x004
+#define OCFB_HTIM	0x008
+#define OCFB_VTIM	0x00c
+#define OCFB_HVLEN	0x010
+#define OCFB_VBARA	0x014
+#define OCFB_PALETTE	0x800
+
+#define OCFB_CTRL_VEN	0x00000001 /* Video Enable */
+#define OCFB_CTRL_HIE	0x00000002 /* HSync Interrupt Enable */
+#define OCFB_CTRL_PC	0x00000800 /* 8-bit Pseudo Color Enable*/
+#define OCFB_CTRL_CD8	0x00000000 /* Color Depth 8 */
+#define OCFB_CTRL_CD16	0x00000200 /* Color Depth 16 */
+#define OCFB_CTRL_CD24	0x00000400 /* Color Depth 24 */
+#define OCFB_CTRL_CD32	0x00000600 /* Color Depth 32 */
+#define OCFB_CTRL_VBL1	0x00000000 /* Burst Length 1 */
+#define OCFB_CTRL_VBL2	0x00000080 /* Burst Length 2 */
+#define OCFB_CTRL_VBL4	0x00000100 /* Burst Length 4 */
+#define OCFB_CTRL_VBL8	0x00000180 /* Burst Length 8 */
+
+#define PALETTE_SIZE	256
+
+#define OCFB_NAME	"OC VGA/LCD"
+
+static char *mode_option;
+
+static const struct fb_videomode default_mode = {
+	/* 640x480 @ 60 Hz, 31.5 kHz hsync */
+	NULL, 60, 640, 480, 39721, 40, 24, 32, 11, 96, 2,
+	0, FB_VMODE_NONINTERLACED
+};
+
+struct ocfb_dev {
+	struct fb_info info;
+	void __iomem *regs;
+	/* flag indicating whether the regs are little endian accessed */
+	int little_endian;
+	/* Physical and virtual addresses of framebuffer */
+	dma_addr_t fb_phys;
+	void __iomem *fb_virt;
+	u32 pseudo_palette[PALETTE_SIZE];
+};
+
+#ifndef MODULE
+static int __init ocfb_setup(char *options)
+{
+	char *curr_opt;
+
+	if (!options || !*options)
+		return 0;
+
+	while ((curr_opt = strsep(&options, ",")) != NULL) {
+		if (!*curr_opt)
+			continue;
+		mode_option = curr_opt;
+	}
+
+	return 0;
+}
+#endif
+
+static inline u32 ocfb_readreg(struct ocfb_dev *fbdev, loff_t offset)
+{
+	if (fbdev->little_endian)
+		return ioread32(fbdev->regs + offset);
+	else
+		return ioread32be(fbdev->regs + offset);
+}
+
+static void ocfb_writereg(struct ocfb_dev *fbdev, loff_t offset, u32 data)
+{
+	if (fbdev->little_endian)
+		iowrite32(data, fbdev->regs + offset);
+	else
+		iowrite32be(data, fbdev->regs + offset);
+}
+
+static int ocfb_setupfb(struct ocfb_dev *fbdev)
+{
+	unsigned long bpp_config;
+	struct fb_var_screeninfo *var = &fbdev->info.var;
+	struct device *dev = fbdev->info.device;
+	u32 hlen;
+	u32 vlen;
+
+	/* Disable display */
+	ocfb_writereg(fbdev, OCFB_CTRL, 0);
+
+	/* Register framebuffer address */
+	fbdev->little_endian = 0;
+	ocfb_writereg(fbdev, OCFB_VBARA, fbdev->fb_phys);
+
+	/* Detect endianess */
+	if (ocfb_readreg(fbdev, OCFB_VBARA) != fbdev->fb_phys) {
+		fbdev->little_endian = 1;
+		ocfb_writereg(fbdev, OCFB_VBARA, fbdev->fb_phys);
+	}
+
+	/* Horizontal timings */
+	ocfb_writereg(fbdev, OCFB_HTIM, (var->hsync_len - 1) << 24 |
+		      (var->left_margin - 1) << 16 | (var->xres - 1));
+
+	/* Vertical timings */
+	ocfb_writereg(fbdev, OCFB_VTIM, (var->vsync_len - 1) << 24 |
+		      (var->upper_margin - 1) << 16 | (var->yres - 1));
+
+	/* Total length of frame */
+	hlen = var->left_margin + var->right_margin + var->hsync_len +
+		var->xres;
+
+	vlen = var->upper_margin + var->lower_margin + var->vsync_len +
+		var->yres;
+
+	ocfb_writereg(fbdev, OCFB_HVLEN, (hlen - 1) << 16 | (vlen - 1));
+
+	bpp_config = OCFB_CTRL_CD8;
+	switch (var->bits_per_pixel) {
+	case 8:
+		if (!var->grayscale)
+			bpp_config |= OCFB_CTRL_PC;  /* enable palette */
+		break;
+
+	case 16:
+		bpp_config |= OCFB_CTRL_CD16;
+		break;
+
+	case 24:
+		bpp_config |= OCFB_CTRL_CD24;
+		break;
+
+	case 32:
+		bpp_config |= OCFB_CTRL_CD32;
+		break;
+
+	default:
+		dev_err(dev, "no bpp specified\n");
+		break;
+	}
+
+	/* maximum (8) VBL (video memory burst length) */
+	bpp_config |= OCFB_CTRL_VBL8;
+
+	/* Enable output */
+	ocfb_writereg(fbdev, OCFB_CTRL, (OCFB_CTRL_VEN | bpp_config));
+
+	return 0;
+}
+
+static int ocfb_setcolreg(unsigned regno, unsigned red, unsigned green,
+			  unsigned blue, unsigned transp,
+			  struct fb_info *info)
+{
+	struct ocfb_dev *fbdev = (struct ocfb_dev *)info->par;
+	u32 color;
+
+	if (regno >= info->cmap.len) {
+		dev_err(info->device, "regno >= cmap.len\n");
+		return 1;
+	}
+
+	if (info->var.grayscale) {
+		/* grayscale = 0.30*R + 0.59*G + 0.11*B */
+		red = green = blue = (red * 77 + green * 151 + blue * 28) >> 8;
+	}
+
+	red >>= (16 - info->var.red.length);
+	green >>= (16 - info->var.green.length);
+	blue >>= (16 - info->var.blue.length);
+	transp >>= (16 - info->var.transp.length);
+
+	if (info->var.bits_per_pixel == 8 && !info->var.grayscale) {
+		regno <<= 2;
+		color = (red << 16) | (green << 8) | blue;
+		ocfb_writereg(fbdev, OCFB_PALETTE + regno, color);
+	} else {
+		((u32 *)(info->pseudo_palette))[regno] =
+			(red << info->var.red.offset) |
+			(green << info->var.green.offset) |
+			(blue << info->var.blue.offset) |
+			(transp << info->var.transp.offset);
+	}
+
+	return 0;
+}
+
+static int ocfb_init_fix(struct ocfb_dev *fbdev)
+{
+	struct fb_var_screeninfo *var = &fbdev->info.var;
+	struct fb_fix_screeninfo *fix = &fbdev->info.fix;
+
+	strcpy(fix->id, OCFB_NAME);
+
+	fix->line_length = var->xres * var->bits_per_pixel/8;
+	fix->smem_len = fix->line_length * var->yres;
+	fix->type = FB_TYPE_PACKED_PIXELS;
+
+	if (var->bits_per_pixel == 8 && !var->grayscale)
+		fix->visual = FB_VISUAL_PSEUDOCOLOR;
+	else
+		fix->visual = FB_VISUAL_TRUECOLOR;
+
+	return 0;
+}
+
+static int ocfb_init_var(struct ocfb_dev *fbdev)
+{
+	struct fb_var_screeninfo *var = &fbdev->info.var;
+
+	var->accel_flags = FB_ACCEL_NONE;
+	var->activate = FB_ACTIVATE_NOW;
+	var->xres_virtual = var->xres;
+	var->yres_virtual = var->yres;
+
+	switch (var->bits_per_pixel) {
+	case 8:
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		var->red.offset = 0;
+		var->red.length = 8;
+		var->green.offset = 0;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		break;
+
+	case 16:
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		var->red.offset = 11;
+		var->red.length = 5;
+		var->green.offset = 5;
+		var->green.length = 6;
+		var->blue.offset = 0;
+		var->blue.length  = 5;
+		break;
+
+	case 24:
+		var->transp.offset = 0;
+		var->transp.length = 0;
+		var->red.offset = 16;
+		var->red.length = 8;
+		var->green.offset = 8;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		break;
+
+	case 32:
+		var->transp.offset = 24;
+		var->transp.length = 8;
+		var->red.offset = 16;
+		var->red.length = 8;
+		var->green.offset = 8;
+		var->green.length = 8;
+		var->blue.offset = 0;
+		var->blue.length = 8;
+		break;
+	}
+
+	return 0;
+}
+
+static const struct fb_ops ocfb_ops = {
+	.owner		= THIS_MODULE,
+	FB_DEFAULT_IOMEM_OPS,
+	.fb_setcolreg	= ocfb_setcolreg,
+};
+
+static int ocfb_probe(struct platform_device *pdev)
+{
+	int ret = 0;
+	struct ocfb_dev *fbdev;
+	int fbsize;
+
+	fbdev = devm_kzalloc(&pdev->dev, sizeof(*fbdev), GFP_KERNEL);
+	if (!fbdev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, fbdev);
+
+	fbdev->info.fbops = &ocfb_ops;
+	fbdev->info.device = &pdev->dev;
+	fbdev->info.par = fbdev;
+
+	/* Video mode setup */
+	if (!fb_find_mode(&fbdev->info.var, &fbdev->info, mode_option,
+			  NULL, 0, &default_mode, 16)) {
+		dev_err(&pdev->dev, "No valid video modes found\n");
+		return -EINVAL;
+	}
+	ocfb_init_var(fbdev);
+	ocfb_init_fix(fbdev);
+
+	fbdev->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(fbdev->regs))
+		return PTR_ERR(fbdev->regs);
+
+	/* Allocate framebuffer memory */
+	fbsize = fbdev->info.fix.smem_len;
+	fbdev->fb_virt = dma_alloc_coherent(&pdev->dev, PAGE_ALIGN(fbsize),
+					    &fbdev->fb_phys, GFP_KERNEL);
+	if (!fbdev->fb_virt) {
+		dev_err(&pdev->dev,
+			"Frame buffer memory allocation failed\n");
+		return -ENOMEM;
+	}
+	fbdev->info.fix.smem_start = fbdev->fb_phys;
+	fbdev->info.screen_base = fbdev->fb_virt;
+	fbdev->info.pseudo_palette = fbdev->pseudo_palette;
+
+	/* Clear framebuffer */
+	memset_io(fbdev->fb_virt, 0, fbsize);
+
+	/* Setup and enable the framebuffer */
+	ocfb_setupfb(fbdev);
+
+	if (fbdev->little_endian)
+		fbdev->info.flags |= FBINFO_FOREIGN_ENDIAN;
+
+	/* Allocate color map */
+	ret = fb_alloc_cmap(&fbdev->info.cmap, PALETTE_SIZE, 0);
+	if (ret) {
+		dev_err(&pdev->dev, "Color map allocation failed\n");
+		goto err_dma_free;
+	}
+
+	/* Register framebuffer */
+	ret = register_framebuffer(&fbdev->info);
+	if (ret) {
+		dev_err(&pdev->dev, "Framebuffer registration failed\n");
+		goto err_dealloc_cmap;
+	}
+
+	return 0;
+
+err_dealloc_cmap:
+	fb_dealloc_cmap(&fbdev->info.cmap);
+
+err_dma_free:
+	dma_free_coherent(&pdev->dev, PAGE_ALIGN(fbsize), fbdev->fb_virt,
+			  fbdev->fb_phys);
+
+	return ret;
+}
+
+static void ocfb_remove(struct platform_device *pdev)
+{
+	struct ocfb_dev *fbdev = platform_get_drvdata(pdev);
+
+	unregister_framebuffer(&fbdev->info);
+	fb_dealloc_cmap(&fbdev->info.cmap);
+	dma_free_coherent(&pdev->dev, PAGE_ALIGN(fbdev->info.fix.smem_len),
+			  fbdev->fb_virt, fbdev->fb_phys);
+
+	/* Disable display */
+	ocfb_writereg(fbdev, OCFB_CTRL, 0);
+
+	platform_set_drvdata(pdev, NULL);
+}
+
+static const struct of_device_id ocfb_match[] = {
+	{ .compatible = "opencores,ocfb", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ocfb_match);
+
+static struct platform_driver ocfb_driver = {
+	.probe  = ocfb_probe,
+	.remove = ocfb_remove,
+	.driver = {
+		.name = "ocfb_fb",
+		.of_match_table = ocfb_match,
+	}
+};
+
+/*
+ * Init and exit routines
+ */
+static int __init ocfb_init(void)
+{
+#ifndef MODULE
+	char *option = NULL;
+
+	if (fb_get_options("ocfb", &option))
+		return -ENODEV;
+	ocfb_setup(option);
+#endif
+	return platform_driver_register(&ocfb_driver);
+}
+
+static void __exit ocfb_exit(void)
+{
+	platform_driver_unregister(&ocfb_driver);
+}
+
+module_init(ocfb_init);
+module_exit(ocfb_exit);
+
+MODULE_AUTHOR("Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>");
+MODULE_DESCRIPTION("OpenCores VGA/LCD 2.0 frame buffer driver");
+MODULE_LICENSE("GPL v2");
+module_param(mode_option, charp, 0);
+MODULE_PARM_DESC(mode_option, "Video mode ('<xres>x<yres>[-<bpp>][@refresh]')");