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, 397 insertions, 0 deletions

diff --git a/drivers/video/fbdev/bw2.c b/drivers/video/fbdev/bw2.c
new file mode 100644
index 000000000..e757462af
--- /dev/null
+++ b/drivers/video/fbdev/bw2.c
@@ -0,0 +1,397 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* bw2.c: BWTWO frame buffer driver
+ *
+ * Copyright (C) 2003, 2006 David S. Miller (davem@davemloft.net)
+ * Copyright (C) 1996,1998 Jakub Jelinek (jj@ultra.linux.cz)
+ * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
+ * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
+ *
+ * Driver layout based loosely on tgafb.c, see that file for credits.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/fb.h>
+#include <linux/mm.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+#include <asm/io.h>
+#include <asm/fbio.h>
+
+#include "sbuslib.h"
+
+/*
+ * Local functions.
+ */
+
+static int bw2_blank(int, struct fb_info *);
+
+static int bw2_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma);
+static int bw2_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg);
+
+/*
+ *  Frame buffer operations
+ */
+
+static const struct fb_ops bw2_ops = {
+	.owner			= THIS_MODULE,
+	FB_DEFAULT_SBUS_OPS(bw2),
+	.fb_blank		= bw2_blank,
+};
+
+/* OBio addresses for the bwtwo registers */
+#define BWTWO_REGISTER_OFFSET 0x400000
+
+struct bt_regs {
+	u32 addr;
+	u32 color_map;
+	u32 control;
+	u32 cursor;
+};
+
+struct bw2_regs {
+	struct bt_regs	cmap;
+	u8	control;
+	u8	status;
+	u8	cursor_start;
+	u8	cursor_end;
+	u8	h_blank_start;
+	u8	h_blank_end;
+	u8	h_sync_start;
+	u8	h_sync_end;
+	u8	comp_sync_end;
+	u8	v_blank_start_high;
+	u8	v_blank_start_low;
+	u8	v_blank_end;
+	u8	v_sync_start;
+	u8	v_sync_end;
+	u8	xfer_holdoff_start;
+	u8	xfer_holdoff_end;
+};
+
+/* Status Register Constants */
+#define BWTWO_SR_RES_MASK	0x70
+#define BWTWO_SR_1600_1280	0x50
+#define BWTWO_SR_1152_900_76_A	0x40
+#define BWTWO_SR_1152_900_76_B	0x60
+#define BWTWO_SR_ID_MASK	0x0f
+#define BWTWO_SR_ID_MONO	0x02
+#define BWTWO_SR_ID_MONO_ECL	0x03
+#define BWTWO_SR_ID_MSYNC	0x04
+#define BWTWO_SR_ID_NOCONN	0x0a
+
+/* Control Register Constants */
+#define BWTWO_CTL_ENABLE_INTS   0x80
+#define BWTWO_CTL_ENABLE_VIDEO  0x40
+#define BWTWO_CTL_ENABLE_TIMING 0x20
+#define BWTWO_CTL_ENABLE_CURCMP 0x10
+#define BWTWO_CTL_XTAL_MASK     0x0C
+#define BWTWO_CTL_DIVISOR_MASK  0x03
+
+/* Status Register Constants */
+#define BWTWO_STAT_PENDING_INT  0x80
+#define BWTWO_STAT_MSENSE_MASK  0x70
+#define BWTWO_STAT_ID_MASK      0x0f
+
+struct bw2_par {
+	spinlock_t		lock;
+	struct bw2_regs		__iomem *regs;
+
+	u32			flags;
+#define BW2_FLAG_BLANKED	0x00000001
+
+	unsigned long		which_io;
+};
+
+/**
+ *      bw2_blank - Optional function.  Blanks the display.
+ *      @blank: the blank mode we want.
+ *      @info: frame buffer structure that represents a single frame buffer
+ */
+static int
+bw2_blank(int blank, struct fb_info *info)
+{
+	struct bw2_par *par = (struct bw2_par *) info->par;
+	struct bw2_regs __iomem *regs = par->regs;
+	unsigned long flags;
+	u8 val;
+
+	spin_lock_irqsave(&par->lock, flags);
+
+	switch (blank) {
+	case FB_BLANK_UNBLANK: /* Unblanking */
+		val = sbus_readb(&regs->control);
+		val |= BWTWO_CTL_ENABLE_VIDEO;
+		sbus_writeb(val, &regs->control);
+		par->flags &= ~BW2_FLAG_BLANKED;
+		break;
+
+	case FB_BLANK_NORMAL: /* Normal blanking */
+	case FB_BLANK_VSYNC_SUSPEND: /* VESA blank (vsync off) */
+	case FB_BLANK_HSYNC_SUSPEND: /* VESA blank (hsync off) */
+	case FB_BLANK_POWERDOWN: /* Poweroff */
+		val = sbus_readb(&regs->control);
+		val &= ~BWTWO_CTL_ENABLE_VIDEO;
+		sbus_writeb(val, &regs->control);
+		par->flags |= BW2_FLAG_BLANKED;
+		break;
+	}
+
+	spin_unlock_irqrestore(&par->lock, flags);
+
+	return 0;
+}
+
+static const struct sbus_mmap_map bw2_mmap_map[] = {
+	{
+		.size = SBUS_MMAP_FBSIZE(1)
+	},
+	{ .size = 0 }
+};
+
+static int bw2_sbusfb_mmap(struct fb_info *info, struct vm_area_struct *vma)
+{
+	struct bw2_par *par = (struct bw2_par *)info->par;
+
+	return sbusfb_mmap_helper(bw2_mmap_map,
+				  info->fix.smem_start, info->fix.smem_len,
+				  par->which_io,
+				  vma);
+}
+
+static int bw2_sbusfb_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg)
+{
+	return sbusfb_ioctl_helper(cmd, arg, info,
+				   FBTYPE_SUN2BW, 1, info->fix.smem_len);
+}
+
+/*
+ *  Initialisation
+ */
+
+static void bw2_init_fix(struct fb_info *info, int linebytes)
+{
+	strscpy(info->fix.id, "bwtwo", sizeof(info->fix.id));
+
+	info->fix.type = FB_TYPE_PACKED_PIXELS;
+	info->fix.visual = FB_VISUAL_MONO01;
+
+	info->fix.line_length = linebytes;
+
+	info->fix.accel = FB_ACCEL_SUN_BWTWO;
+}
+
+static u8 bw2regs_1600[] = {
+	0x14, 0x8b,	0x15, 0x28,	0x16, 0x03,	0x17, 0x13,
+	0x18, 0x7b,	0x19, 0x05,	0x1a, 0x34,	0x1b, 0x2e,
+	0x1c, 0x00,	0x1d, 0x0a,	0x1e, 0xff,	0x1f, 0x01,
+	0x10, 0x21,	0
+};
+
+static u8 bw2regs_ecl[] = {
+	0x14, 0x65,	0x15, 0x1e,	0x16, 0x04,	0x17, 0x0c,
+	0x18, 0x5e,	0x19, 0x03,	0x1a, 0xa7,	0x1b, 0x23,
+	0x1c, 0x00,	0x1d, 0x08,	0x1e, 0xff,	0x1f, 0x01,
+	0x10, 0x20,	0
+};
+
+static u8 bw2regs_analog[] = {
+	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x03,	0x17, 0x13,
+	0x18, 0xb0,	0x19, 0x03,	0x1a, 0xa6,	0x1b, 0x22,
+	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
+	0x10, 0x20,	0
+};
+
+static u8 bw2regs_76hz[] = {
+	0x14, 0xb7,	0x15, 0x27,	0x16, 0x03,	0x17, 0x0f,
+	0x18, 0xae,	0x19, 0x03,	0x1a, 0xae,	0x1b, 0x2a,
+	0x1c, 0x01,	0x1d, 0x09,	0x1e, 0xff,	0x1f, 0x01,
+	0x10, 0x24,	0
+};
+
+static u8 bw2regs_66hz[] = {
+	0x14, 0xbb,	0x15, 0x2b,	0x16, 0x04,	0x17, 0x14,
+	0x18, 0xae,	0x19, 0x03,	0x1a, 0xa8,	0x1b, 0x24,
+	0x1c, 0x01,	0x1d, 0x05,	0x1e, 0xff,	0x1f, 0x01,
+	0x10, 0x20,	0
+};
+
+static int bw2_do_default_mode(struct bw2_par *par, struct fb_info *info,
+			       int *linebytes)
+{
+	u8 status, mon;
+	u8 *p;
+
+	status = sbus_readb(&par->regs->status);
+	mon = status & BWTWO_SR_RES_MASK;
+	switch (status & BWTWO_SR_ID_MASK) {
+	case BWTWO_SR_ID_MONO_ECL:
+		if (mon == BWTWO_SR_1600_1280) {
+			p = bw2regs_1600;
+			info->var.xres = info->var.xres_virtual = 1600;
+			info->var.yres = info->var.yres_virtual = 1280;
+			*linebytes = 1600 / 8;
+		} else
+			p = bw2regs_ecl;
+		break;
+
+	case BWTWO_SR_ID_MONO:
+		p = bw2regs_analog;
+		break;
+
+	case BWTWO_SR_ID_MSYNC:
+		if (mon == BWTWO_SR_1152_900_76_A ||
+		    mon == BWTWO_SR_1152_900_76_B)
+			p = bw2regs_76hz;
+		else
+			p = bw2regs_66hz;
+		break;
+
+	case BWTWO_SR_ID_NOCONN:
+		return 0;
+
+	default:
+		printk(KERN_ERR "bw2: can't handle SR %02x\n",
+		       status);
+		return -EINVAL;
+	}
+	for ( ; *p; p += 2) {
+		u8 __iomem *regp = &((u8 __iomem *)par->regs)[p[0]];
+		sbus_writeb(p[1], regp);
+	}
+	return 0;
+}
+
+static int bw2_probe(struct platform_device *op)
+{
+	struct device_node *dp = op->dev.of_node;
+	struct fb_info *info;
+	struct bw2_par *par;
+	int linebytes, err;
+
+	info = framebuffer_alloc(sizeof(struct bw2_par), &op->dev);
+
+	err = -ENOMEM;
+	if (!info)
+		goto out_err;
+	par = info->par;
+
+	spin_lock_init(&par->lock);
+
+	info->fix.smem_start = op->resource[0].start;
+	par->which_io = op->resource[0].flags & IORESOURCE_BITS;
+
+	sbusfb_fill_var(&info->var, dp, 1);
+	linebytes = of_getintprop_default(dp, "linebytes",
+					  info->var.xres);
+
+	info->var.red.length = info->var.green.length =
+		info->var.blue.length = info->var.bits_per_pixel;
+	info->var.red.offset = info->var.green.offset =
+		info->var.blue.offset = 0;
+
+	par->regs = of_ioremap(&op->resource[0], BWTWO_REGISTER_OFFSET,
+			       sizeof(struct bw2_regs), "bw2 regs");
+	if (!par->regs)
+		goto out_release_fb;
+
+	if (!of_property_present(dp, "width")) {
+		err = bw2_do_default_mode(par, info, &linebytes);
+		if (err)
+			goto out_unmap_regs;
+	}
+
+	info->fix.smem_len = PAGE_ALIGN(linebytes * info->var.yres);
+
+	info->fbops = &bw2_ops;
+
+	info->screen_base = of_ioremap(&op->resource[0], 0,
+				       info->fix.smem_len, "bw2 ram");
+	if (!info->screen_base) {
+		err = -ENOMEM;
+		goto out_unmap_regs;
+	}
+
+	bw2_blank(FB_BLANK_UNBLANK, info);
+
+	bw2_init_fix(info, linebytes);
+
+	err = register_framebuffer(info);
+	if (err < 0)
+		goto out_unmap_screen;
+
+	dev_set_drvdata(&op->dev, info);
+
+	printk(KERN_INFO "%pOF: bwtwo at %lx:%lx\n",
+	       dp, par->which_io, info->fix.smem_start);
+
+	return 0;
+
+out_unmap_screen:
+	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
+
+out_unmap_regs:
+	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
+
+out_release_fb:
+	framebuffer_release(info);
+
+out_err:
+	return err;
+}
+
+static void bw2_remove(struct platform_device *op)
+{
+	struct fb_info *info = dev_get_drvdata(&op->dev);
+	struct bw2_par *par = info->par;
+
+	unregister_framebuffer(info);
+
+	of_iounmap(&op->resource[0], par->regs, sizeof(struct bw2_regs));
+	of_iounmap(&op->resource[0], info->screen_base, info->fix.smem_len);
+
+	framebuffer_release(info);
+}
+
+static const struct of_device_id bw2_match[] = {
+	{
+		.name = "bwtwo",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, bw2_match);
+
+static struct platform_driver bw2_driver = {
+	.driver = {
+		.name = "bw2",
+		.of_match_table = bw2_match,
+	},
+	.probe		= bw2_probe,
+	.remove		= bw2_remove,
+};
+
+static int __init bw2_init(void)
+{
+	if (fb_get_options("bw2fb", NULL))
+		return -ENODEV;
+
+	return platform_driver_register(&bw2_driver);
+}
+
+static void __exit bw2_exit(void)
+{
+	platform_driver_unregister(&bw2_driver);
+}
+
+module_init(bw2_init);
+module_exit(bw2_exit);
+
+MODULE_DESCRIPTION("framebuffer driver for BWTWO chipsets");
+MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");
+MODULE_VERSION("2.0");
+MODULE_LICENSE("GPL");