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, 489 insertions, 0 deletions

diff --git a/drivers/video/fbdev/vt8500lcdfb.c b/drivers/video/fbdev/vt8500lcdfb.c
new file mode 100644
index 000000000..85c7a99a7
--- /dev/null
+++ b/drivers/video/fbdev/vt8500lcdfb.c
@@ -0,0 +1,489 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  linux/drivers/video/vt8500lcdfb.c
+ *
+ *  Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * Based on skeletonfb.c and pxafb.c
+ */
+
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/wait.h>
+#include <video/of_display_timing.h>
+
+#include "vt8500lcdfb.h"
+#include "wmt_ge_rops.h"
+
+#ifdef CONFIG_OF
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/memblock.h>
+#endif
+
+
+#define to_vt8500lcd_info(__info) container_of(__info, \
+						struct vt8500lcd_info, fb)
+
+static int vt8500lcd_set_par(struct fb_info *info)
+{
+	struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+	int reg_bpp = 5; /* 16bpp */
+	int i;
+	unsigned long control0;
+
+	if (!fbi)
+		return -EINVAL;
+
+	if (info->var.bits_per_pixel <= 8) {
+		/* palettized */
+		info->var.red.offset    = 0;
+		info->var.red.length    = info->var.bits_per_pixel;
+		info->var.red.msb_right = 0;
+
+		info->var.green.offset  = 0;
+		info->var.green.length  = info->var.bits_per_pixel;
+		info->var.green.msb_right = 0;
+
+		info->var.blue.offset   = 0;
+		info->var.blue.length   = info->var.bits_per_pixel;
+		info->var.blue.msb_right = 0;
+
+		info->var.transp.offset = 0;
+		info->var.transp.length = 0;
+		info->var.transp.msb_right = 0;
+
+		info->fix.visual = FB_VISUAL_PSEUDOCOLOR;
+		info->fix.line_length = info->var.xres_virtual /
+						(8/info->var.bits_per_pixel);
+	} else {
+		/* non-palettized */
+		info->var.transp.offset = 0;
+		info->var.transp.length = 0;
+		info->var.transp.msb_right = 0;
+
+		if (info->var.bits_per_pixel == 16) {
+			/* RGB565 */
+			info->var.red.offset = 11;
+			info->var.red.length = 5;
+			info->var.red.msb_right = 0;
+			info->var.green.offset = 5;
+			info->var.green.length = 6;
+			info->var.green.msb_right = 0;
+			info->var.blue.offset = 0;
+			info->var.blue.length = 5;
+			info->var.blue.msb_right = 0;
+		} else {
+			/* Equal depths per channel */
+			info->var.red.offset = info->var.bits_per_pixel
+							* 2 / 3;
+			info->var.red.length = info->var.bits_per_pixel / 3;
+			info->var.red.msb_right = 0;
+			info->var.green.offset = info->var.bits_per_pixel / 3;
+			info->var.green.length = info->var.bits_per_pixel / 3;
+			info->var.green.msb_right = 0;
+			info->var.blue.offset = 0;
+			info->var.blue.length = info->var.bits_per_pixel / 3;
+			info->var.blue.msb_right = 0;
+		}
+
+		info->fix.visual = FB_VISUAL_TRUECOLOR;
+		info->fix.line_length = info->var.bits_per_pixel > 16 ?
+					info->var.xres_virtual << 2 :
+					info->var.xres_virtual << 1;
+	}
+
+	for (i = 0; i < 8; i++) {
+		if (bpp_values[i] == info->var.bits_per_pixel)
+			reg_bpp = i;
+	}
+
+	control0 = readl(fbi->regbase) & ~0xf;
+	writel(0, fbi->regbase);
+	while (readl(fbi->regbase + 0x38) & 0x10)
+		/* wait */;
+	writel((((info->var.hsync_len - 1) & 0x3f) << 26)
+		| ((info->var.left_margin & 0xff) << 18)
+		| (((info->var.xres - 1) & 0x3ff) << 8)
+		| (info->var.right_margin & 0xff), fbi->regbase + 0x4);
+	writel((((info->var.vsync_len - 1) & 0x3f) << 26)
+		| ((info->var.upper_margin & 0xff) << 18)
+		| (((info->var.yres - 1) & 0x3ff) << 8)
+		| (info->var.lower_margin & 0xff), fbi->regbase + 0x8);
+	writel((((info->var.yres - 1) & 0x400) << 2)
+		| ((info->var.xres - 1) & 0x400), fbi->regbase + 0x10);
+	writel(0x80000000, fbi->regbase + 0x20);
+	writel(control0 | (reg_bpp << 1) | 0x100, fbi->regbase);
+
+	return 0;
+}
+
+static inline u_int chan_to_field(u_int chan, struct fb_bitfield *bf)
+{
+	chan &= 0xffff;
+	chan >>= 16 - bf->length;
+	return chan << bf->offset;
+}
+
+static int vt8500lcd_setcolreg(unsigned regno, unsigned red, unsigned green,
+			   unsigned blue, unsigned transp,
+			   struct fb_info *info) {
+	struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+	int ret = 1;
+	unsigned int val;
+	if (regno >= 256)
+		return -EINVAL;
+
+	if (info->var.grayscale)
+		red = green = blue =
+			(19595 * red + 38470 * green + 7471 * blue) >> 16;
+
+	switch (fbi->fb.fix.visual) {
+	case FB_VISUAL_TRUECOLOR:
+		if (regno < 16) {
+			u32 *pal = fbi->fb.pseudo_palette;
+
+			val  = chan_to_field(red, &fbi->fb.var.red);
+			val |= chan_to_field(green, &fbi->fb.var.green);
+			val |= chan_to_field(blue, &fbi->fb.var.blue);
+
+			pal[regno] = val;
+			ret = 0;
+		}
+		break;
+
+	case FB_VISUAL_STATIC_PSEUDOCOLOR:
+	case FB_VISUAL_PSEUDOCOLOR:
+		writew((red & 0xf800)
+		      | ((green >> 5) & 0x7e0)
+		      | ((blue >> 11) & 0x1f),
+		       fbi->palette_cpu + sizeof(u16) * regno);
+		break;
+	}
+
+	return ret;
+}
+
+static int vt8500lcd_ioctl(struct fb_info *info, unsigned int cmd,
+			 unsigned long arg)
+{
+	int ret = 0;
+	struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+
+	if (cmd == FBIO_WAITFORVSYNC) {
+		/* Unmask End of Frame interrupt */
+		writel(0xffffffff ^ (1 << 3), fbi->regbase + 0x3c);
+		ret = wait_event_interruptible_timeout(fbi->wait,
+			readl(fbi->regbase + 0x38) & (1 << 3), HZ / 10);
+		/* Mask back to reduce unwanted interrupt traffic */
+		writel(0xffffffff, fbi->regbase + 0x3c);
+		if (ret < 0)
+			return ret;
+		if (ret == 0)
+			return -ETIMEDOUT;
+	}
+
+	return ret;
+}
+
+static int vt8500lcd_pan_display(struct fb_var_screeninfo *var,
+				struct fb_info *info)
+{
+	unsigned pixlen = info->fix.line_length / info->var.xres_virtual;
+	unsigned off = pixlen * var->xoffset
+		      + info->fix.line_length * var->yoffset;
+	struct vt8500lcd_info *fbi = to_vt8500lcd_info(info);
+
+	writel((1 << 31)
+	     | (((info->var.xres_virtual - info->var.xres) * pixlen / 4) << 20)
+	     | (off >> 2), fbi->regbase + 0x20);
+	return 0;
+}
+
+/*
+ * vt8500lcd_blank():
+ *	Blank the display by setting all palette values to zero.  Note,
+ * 	True Color modes do not really use the palette, so this will not
+ *      blank the display in all modes.
+ */
+static int vt8500lcd_blank(int blank, struct fb_info *info)
+{
+	int i;
+
+	switch (blank) {
+	case FB_BLANK_POWERDOWN:
+	case FB_BLANK_VSYNC_SUSPEND:
+	case FB_BLANK_HSYNC_SUSPEND:
+	case FB_BLANK_NORMAL:
+		if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
+		    info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
+			for (i = 0; i < 256; i++)
+				vt8500lcd_setcolreg(i, 0, 0, 0, 0, info);
+		fallthrough;
+	case FB_BLANK_UNBLANK:
+		if (info->fix.visual == FB_VISUAL_PSEUDOCOLOR ||
+		    info->fix.visual == FB_VISUAL_STATIC_PSEUDOCOLOR)
+			fb_set_cmap(&info->cmap, info);
+	}
+	return 0;
+}
+
+static const struct fb_ops vt8500lcd_ops = {
+	.owner		= THIS_MODULE,
+	__FB_DEFAULT_DMAMEM_OPS_RDWR,
+	.fb_set_par	= vt8500lcd_set_par,
+	.fb_setcolreg	= vt8500lcd_setcolreg,
+	.fb_fillrect	= wmt_ge_fillrect,
+	.fb_copyarea	= wmt_ge_copyarea,
+	.fb_imageblit	= sys_imageblit,
+	.fb_sync	= wmt_ge_sync,
+	.fb_ioctl	= vt8500lcd_ioctl,
+	.fb_pan_display	= vt8500lcd_pan_display,
+	.fb_blank	= vt8500lcd_blank,
+	// .fb_mmap needs DMA mmap
+};
+
+static irqreturn_t vt8500lcd_handle_irq(int irq, void *dev_id)
+{
+	struct vt8500lcd_info *fbi = dev_id;
+
+	if (readl(fbi->regbase + 0x38) & (1 << 3))
+		wake_up_interruptible(&fbi->wait);
+
+	writel(0xffffffff, fbi->regbase + 0x38);
+	return IRQ_HANDLED;
+}
+
+static int vt8500lcd_probe(struct platform_device *pdev)
+{
+	struct vt8500lcd_info *fbi;
+	struct resource *res;
+	struct display_timings *disp_timing;
+	void *addr;
+	int irq, ret;
+
+	struct fb_videomode	of_mode;
+	u32			bpp;
+	dma_addr_t fb_mem_phys;
+	unsigned long fb_mem_len;
+	void *fb_mem_virt;
+
+	ret = -ENOMEM;
+	fbi = NULL;
+
+	fbi = devm_kzalloc(&pdev->dev, sizeof(struct vt8500lcd_info)
+			+ sizeof(u32) * 16, GFP_KERNEL);
+	if (!fbi)
+		return -ENOMEM;
+
+	strcpy(fbi->fb.fix.id, "VT8500 LCD");
+
+	fbi->fb.fix.type	= FB_TYPE_PACKED_PIXELS;
+	fbi->fb.fix.xpanstep	= 0;
+	fbi->fb.fix.ypanstep	= 1;
+	fbi->fb.fix.ywrapstep	= 0;
+	fbi->fb.fix.accel	= FB_ACCEL_NONE;
+
+	fbi->fb.var.nonstd	= 0;
+	fbi->fb.var.activate	= FB_ACTIVATE_NOW;
+	fbi->fb.var.height	= -1;
+	fbi->fb.var.width	= -1;
+	fbi->fb.var.vmode	= FB_VMODE_NONINTERLACED;
+
+	fbi->fb.fbops		= &vt8500lcd_ops;
+	fbi->fb.flags		= FBINFO_HWACCEL_COPYAREA
+				| FBINFO_HWACCEL_FILLRECT
+				| FBINFO_HWACCEL_YPAN
+				| FBINFO_VIRTFB
+				| FBINFO_PARTIAL_PAN_OK;
+	fbi->fb.node		= -1;
+
+	addr = fbi;
+	addr = addr + sizeof(struct vt8500lcd_info);
+	fbi->fb.pseudo_palette	= addr;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		dev_err(&pdev->dev, "no I/O memory resource defined\n");
+		return -ENODEV;
+	}
+
+	res = request_mem_region(res->start, resource_size(res), "vt8500lcd");
+	if (res == NULL) {
+		dev_err(&pdev->dev, "failed to request I/O memory\n");
+		return -EBUSY;
+	}
+
+	fbi->regbase = ioremap(res->start, resource_size(res));
+	if (fbi->regbase == NULL) {
+		dev_err(&pdev->dev, "failed to map I/O memory\n");
+		ret = -EBUSY;
+		goto failed_free_res;
+	}
+
+	disp_timing = of_get_display_timings(pdev->dev.of_node);
+	if (!disp_timing) {
+		ret = -EINVAL;
+		goto failed_free_io;
+	}
+
+	ret = of_get_fb_videomode(pdev->dev.of_node, &of_mode,
+							OF_USE_NATIVE_MODE);
+	if (ret)
+		goto failed_free_io;
+
+	ret = of_property_read_u32(pdev->dev.of_node, "bits-per-pixel", &bpp);
+	if (ret)
+		goto failed_free_io;
+
+	/* try allocating the framebuffer */
+	fb_mem_len = of_mode.xres * of_mode.yres * 2 * (bpp / 8);
+	fb_mem_virt = dma_alloc_coherent(&pdev->dev, fb_mem_len, &fb_mem_phys,
+				GFP_KERNEL);
+	if (!fb_mem_virt) {
+		pr_err("%s: Failed to allocate framebuffer\n", __func__);
+		ret = -ENOMEM;
+		goto failed_free_io;
+	}
+
+	fbi->fb.fix.smem_start	= fb_mem_phys;
+	fbi->fb.fix.smem_len	= fb_mem_len;
+	fbi->fb.screen_buffer	= fb_mem_virt;
+
+	fbi->palette_size	= PAGE_ALIGN(512);
+	fbi->palette_cpu	= dma_alloc_coherent(&pdev->dev,
+						     fbi->palette_size,
+						     &fbi->palette_phys,
+						     GFP_KERNEL);
+	if (fbi->palette_cpu == NULL) {
+		dev_err(&pdev->dev, "Failed to allocate palette buffer\n");
+		ret = -ENOMEM;
+		goto failed_free_mem_virt;
+	}
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		ret = -ENODEV;
+		goto failed_free_palette;
+	}
+
+	ret = request_irq(irq, vt8500lcd_handle_irq, 0, "LCD", fbi);
+	if (ret) {
+		dev_err(&pdev->dev, "request_irq failed: %d\n", ret);
+		ret = -EBUSY;
+		goto failed_free_palette;
+	}
+
+	init_waitqueue_head(&fbi->wait);
+
+	if (fb_alloc_cmap(&fbi->fb.cmap, 256, 0) < 0) {
+		dev_err(&pdev->dev, "Failed to allocate color map\n");
+		ret = -ENOMEM;
+		goto failed_free_irq;
+	}
+
+	fb_videomode_to_var(&fbi->fb.var, &of_mode);
+
+	fbi->fb.var.xres_virtual	= of_mode.xres;
+	fbi->fb.var.yres_virtual	= of_mode.yres * 2;
+	fbi->fb.var.bits_per_pixel	= bpp;
+
+	ret = vt8500lcd_set_par(&fbi->fb);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to set parameters\n");
+		goto failed_free_cmap;
+	}
+
+	writel(fbi->fb.fix.smem_start >> 22, fbi->regbase + 0x1c);
+	writel((fbi->palette_phys & 0xfffffe00) | 1, fbi->regbase + 0x18);
+
+	platform_set_drvdata(pdev, fbi);
+
+	ret = register_framebuffer(&fbi->fb);
+	if (ret < 0) {
+		dev_err(&pdev->dev,
+			"Failed to register framebuffer device: %d\n", ret);
+		goto failed_free_cmap;
+	}
+
+	/*
+	 * Ok, now enable the LCD controller
+	 */
+	writel(readl(fbi->regbase) | 1, fbi->regbase);
+
+	return 0;
+
+failed_free_cmap:
+	if (fbi->fb.cmap.len)
+		fb_dealloc_cmap(&fbi->fb.cmap);
+failed_free_irq:
+	free_irq(irq, fbi);
+failed_free_palette:
+	dma_free_coherent(&pdev->dev, fbi->palette_size,
+			  fbi->palette_cpu, fbi->palette_phys);
+failed_free_mem_virt:
+	dma_free_coherent(&pdev->dev, fbi->fb.fix.smem_len,
+			  fbi->fb.screen_buffer, fbi->fb.fix.smem_start);
+failed_free_io:
+	iounmap(fbi->regbase);
+failed_free_res:
+	release_mem_region(res->start, resource_size(res));
+	return ret;
+}
+
+static void vt8500lcd_remove(struct platform_device *pdev)
+{
+	struct vt8500lcd_info *fbi = platform_get_drvdata(pdev);
+	struct resource *res;
+	int irq;
+
+	unregister_framebuffer(&fbi->fb);
+
+	writel(0, fbi->regbase);
+
+	if (fbi->fb.cmap.len)
+		fb_dealloc_cmap(&fbi->fb.cmap);
+
+	irq = platform_get_irq(pdev, 0);
+	free_irq(irq, fbi);
+
+	dma_free_coherent(&pdev->dev, fbi->palette_size,
+			  fbi->palette_cpu, fbi->palette_phys);
+
+	iounmap(fbi->regbase);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	release_mem_region(res->start, resource_size(res));
+}
+
+static const struct of_device_id via_dt_ids[] = {
+	{ .compatible = "via,vt8500-fb", },
+	{}
+};
+
+static struct platform_driver vt8500lcd_driver = {
+	.probe		= vt8500lcd_probe,
+	.remove		= vt8500lcd_remove,
+	.driver		= {
+		.name	= "vt8500-lcd",
+		.of_match_table = of_match_ptr(via_dt_ids),
+	},
+};
+
+module_platform_driver(vt8500lcd_driver);
+
+MODULE_AUTHOR("Alexey Charkov <alchark@gmail.com>");
+MODULE_DESCRIPTION("LCD controller driver for VIA VT8500");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, via_dt_ids);