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, 408 insertions, 0 deletions

diff --git a/drivers/video/fbdev/pmagb-b-fb.c b/drivers/video/fbdev/pmagb-b-fb.c
new file mode 100644
index 000000000..643249246
--- /dev/null
+++ b/drivers/video/fbdev/pmagb-b-fb.c
@@ -0,0 +1,408 @@
+/*
+ *	linux/drivers/video/pmagb-b-fb.c
+ *
+ *	PMAGB-B TURBOchannel Smart Frame Buffer (SFB) card support,
+ *	derived from:
+ *	"HP300 Topcat framebuffer support (derived from macfb of all things)
+ *	Phil Blundell <philb@gnu.org> 1998", the original code can be
+ *	found in the file hpfb.c in the same directory.
+ *
+ *	DECstation related code Copyright (C) 1999, 2000, 2001 by
+ *	Michael Engel <engel@unix-ag.org>,
+ *	Karsten Merker <merker@linuxtag.org> and
+ *	Harald Koerfgen.
+ *	Copyright (c) 2005, 2006  Maciej W. Rozycki
+ *
+ *	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/compiler.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/fb.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/tc.h>
+#include <linux/types.h>
+
+#include <asm/io.h>
+
+#include <video/pmagb-b-fb.h>
+
+
+struct pmagbbfb_par {
+	volatile void __iomem *mmio;
+	volatile void __iomem *smem;
+	volatile u32 __iomem *sfb;
+	volatile u32 __iomem *dac;
+	unsigned int osc0;
+	unsigned int osc1;
+	int slot;
+};
+
+
+static const struct fb_var_screeninfo pmagbbfb_defined = {
+	.bits_per_pixel	= 8,
+	.red.length	= 8,
+	.green.length	= 8,
+	.blue.length	= 8,
+	.activate	= FB_ACTIVATE_NOW,
+	.height		= -1,
+	.width		= -1,
+	.accel_flags	= FB_ACCEL_NONE,
+	.sync		= FB_SYNC_ON_GREEN,
+	.vmode		= FB_VMODE_NONINTERLACED,
+};
+
+static const struct fb_fix_screeninfo pmagbbfb_fix = {
+	.id		= "PMAGB-BA",
+	.smem_len	= (2048 * 1024),
+	.type		= FB_TYPE_PACKED_PIXELS,
+	.visual		= FB_VISUAL_PSEUDOCOLOR,
+	.mmio_len	= PMAGB_B_FBMEM,
+};
+
+
+static inline void sfb_write(struct pmagbbfb_par *par, unsigned int reg, u32 v)
+{
+	writel(v, par->sfb + reg / 4);
+}
+
+static inline u32 sfb_read(struct pmagbbfb_par *par, unsigned int reg)
+{
+	return readl(par->sfb + reg / 4);
+}
+
+static inline void dac_write(struct pmagbbfb_par *par, unsigned int reg, u8 v)
+{
+	writeb(v, par->dac + reg / 4);
+}
+
+static inline u8 dac_read(struct pmagbbfb_par *par, unsigned int reg)
+{
+	return readb(par->dac + reg / 4);
+}
+
+static inline void gp0_write(struct pmagbbfb_par *par, u32 v)
+{
+	writel(v, par->mmio + PMAGB_B_GP0);
+}
+
+
+/*
+ * Set the palette.
+ */
+static int pmagbbfb_setcolreg(unsigned int regno, unsigned int red,
+			      unsigned int green, unsigned int blue,
+			      unsigned int transp, struct fb_info *info)
+{
+	struct pmagbbfb_par *par = info->par;
+
+	if (regno >= info->cmap.len)
+		return 1;
+
+	red   >>= 8;	/* The cmap fields are 16 bits    */
+	green >>= 8;	/* wide, but the hardware colormap */
+	blue  >>= 8;	/* registers are only 8 bits wide */
+
+	mb();
+	dac_write(par, BT459_ADDR_LO, regno);
+	dac_write(par, BT459_ADDR_HI, 0x00);
+	wmb();
+	dac_write(par, BT459_CMAP, red);
+	wmb();
+	dac_write(par, BT459_CMAP, green);
+	wmb();
+	dac_write(par, BT459_CMAP, blue);
+
+	return 0;
+}
+
+static const struct fb_ops pmagbbfb_ops = {
+	.owner		= THIS_MODULE,
+	FB_DEFAULT_IOMEM_OPS,
+	.fb_setcolreg	= pmagbbfb_setcolreg,
+};
+
+
+/*
+ * Turn the hardware cursor off.
+ */
+static void pmagbbfb_erase_cursor(struct fb_info *info)
+{
+	struct pmagbbfb_par *par = info->par;
+
+	mb();
+	dac_write(par, BT459_ADDR_LO, 0x00);
+	dac_write(par, BT459_ADDR_HI, 0x03);
+	wmb();
+	dac_write(par, BT459_DATA, 0x00);
+}
+
+/*
+ * Set up screen parameters.
+ */
+static void pmagbbfb_screen_setup(struct fb_info *info)
+{
+	struct pmagbbfb_par *par = info->par;
+
+	info->var.xres = ((sfb_read(par, SFB_REG_VID_HOR) >>
+			   SFB_VID_HOR_PIX_SHIFT) & SFB_VID_HOR_PIX_MASK) * 4;
+	info->var.xres_virtual = info->var.xres;
+	info->var.yres = (sfb_read(par, SFB_REG_VID_VER) >>
+			  SFB_VID_VER_SL_SHIFT) & SFB_VID_VER_SL_MASK;
+	info->var.yres_virtual = info->var.yres;
+	info->var.left_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				  SFB_VID_HOR_BP_SHIFT) &
+				 SFB_VID_HOR_BP_MASK) * 4;
+	info->var.right_margin = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				   SFB_VID_HOR_FP_SHIFT) &
+				  SFB_VID_HOR_FP_MASK) * 4;
+	info->var.upper_margin = (sfb_read(par, SFB_REG_VID_VER) >>
+				  SFB_VID_VER_BP_SHIFT) & SFB_VID_VER_BP_MASK;
+	info->var.lower_margin = (sfb_read(par, SFB_REG_VID_VER) >>
+				  SFB_VID_VER_FP_SHIFT) & SFB_VID_VER_FP_MASK;
+	info->var.hsync_len = ((sfb_read(par, SFB_REG_VID_HOR) >>
+				SFB_VID_HOR_SYN_SHIFT) &
+			       SFB_VID_HOR_SYN_MASK) * 4;
+	info->var.vsync_len = (sfb_read(par, SFB_REG_VID_VER) >>
+			       SFB_VID_VER_SYN_SHIFT) & SFB_VID_VER_SYN_MASK;
+
+	info->fix.line_length = info->var.xres;
+};
+
+/*
+ * Determine oscillator configuration.
+ */
+static void pmagbbfb_osc_setup(struct fb_info *info)
+{
+	static unsigned int pmagbbfb_freqs[] = {
+		130808, 119843, 104000, 92980, 74370, 72800,
+		69197, 66000, 65000, 50350, 36000, 32000, 25175
+	};
+	struct pmagbbfb_par *par = info->par;
+	struct tc_bus *tbus = to_tc_dev(info->device)->bus;
+	u32 count0 = 8, count1 = 8, counttc = 16 * 256 + 8;
+	u32 freq0, freq1, freqtc = tc_get_speed(tbus) / 250;
+	int i, j;
+
+	gp0_write(par, 0);				/* select Osc0 */
+	for (j = 0; j < 16; j++) {
+		mb();
+		sfb_write(par, SFB_REG_TCCLK_COUNT, 0);
+		mb();
+		for (i = 0; i < 100; i++) {	/* nominally max. 20.5us */
+			if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
+				break;
+			udelay(1);
+		}
+		count0 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
+	}
+
+	gp0_write(par, 1);				/* select Osc1 */
+	for (j = 0; j < 16; j++) {
+		mb();
+		sfb_write(par, SFB_REG_TCCLK_COUNT, 0);
+
+		for (i = 0; i < 100; i++) {	/* nominally max. 20.5us */
+			if (sfb_read(par, SFB_REG_TCCLK_COUNT) == 0)
+				break;
+			udelay(1);
+		}
+		count1 += sfb_read(par, SFB_REG_VIDCLK_COUNT);
+	}
+
+	freq0 = (freqtc * count0 + counttc / 2) / counttc;
+	par->osc0 = freq0;
+	if (freq0 >= pmagbbfb_freqs[0] - (pmagbbfb_freqs[0] + 32) / 64 &&
+	    freq0 <= pmagbbfb_freqs[0] + (pmagbbfb_freqs[0] + 32) / 64)
+		par->osc0 = pmagbbfb_freqs[0];
+
+	freq1 = (par->osc0 * count1 + count0 / 2) / count0;
+	par->osc1 = freq1;
+	for (i = 0; i < ARRAY_SIZE(pmagbbfb_freqs); i++)
+		if (freq1 >= pmagbbfb_freqs[i] -
+			     (pmagbbfb_freqs[i] + 128) / 256 &&
+		    freq1 <= pmagbbfb_freqs[i] +
+			     (pmagbbfb_freqs[i] + 128) / 256) {
+			par->osc1 = pmagbbfb_freqs[i];
+			break;
+		}
+
+	if (par->osc0 - par->osc1 <= (par->osc0 + par->osc1 + 256) / 512 ||
+	    par->osc1 - par->osc0 <= (par->osc0 + par->osc1 + 256) / 512)
+		par->osc1 = 0;
+
+	gp0_write(par, par->osc1 != 0);			/* reselect OscX */
+
+	info->var.pixclock = par->osc1 ?
+			     (1000000000 + par->osc1 / 2) / par->osc1 :
+			     (1000000000 + par->osc0 / 2) / par->osc0;
+};
+
+
+static int pmagbbfb_probe(struct device *dev)
+{
+	struct tc_dev *tdev = to_tc_dev(dev);
+	resource_size_t start, len;
+	struct fb_info *info;
+	struct pmagbbfb_par *par;
+	char freq0[12], freq1[12];
+	u32 vid_base;
+	int err;
+
+	info = framebuffer_alloc(sizeof(struct pmagbbfb_par), dev);
+	if (!info)
+		return -ENOMEM;
+
+	par = info->par;
+	dev_set_drvdata(dev, info);
+
+	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
+		printk(KERN_ERR "%s: Cannot allocate color map\n",
+		       dev_name(dev));
+		err = -ENOMEM;
+		goto err_alloc;
+	}
+
+	info->fbops = &pmagbbfb_ops;
+	info->fix = pmagbbfb_fix;
+	info->var = pmagbbfb_defined;
+
+	/* Request the I/O MEM resource.  */
+	start = tdev->resource.start;
+	len = tdev->resource.end - start + 1;
+	if (!request_mem_region(start, len, dev_name(dev))) {
+		printk(KERN_ERR "%s: Cannot reserve FB region\n",
+		       dev_name(dev));
+		err = -EBUSY;
+		goto err_cmap;
+	}
+
+	/* MMIO mapping setup.  */
+	info->fix.mmio_start = start;
+	par->mmio = ioremap(info->fix.mmio_start, info->fix.mmio_len);
+	if (!par->mmio) {
+		printk(KERN_ERR "%s: Cannot map MMIO\n", dev_name(dev));
+		err = -ENOMEM;
+		goto err_resource;
+	}
+	par->sfb = par->mmio + PMAGB_B_SFB;
+	par->dac = par->mmio + PMAGB_B_BT459;
+
+	/* Frame buffer mapping setup.  */
+	info->fix.smem_start = start + PMAGB_B_FBMEM;
+	par->smem = ioremap(info->fix.smem_start, info->fix.smem_len);
+	if (!par->smem) {
+		printk(KERN_ERR "%s: Cannot map FB\n", dev_name(dev));
+		err = -ENOMEM;
+		goto err_mmio_map;
+	}
+	vid_base = sfb_read(par, SFB_REG_VID_BASE);
+	info->screen_base = (void __iomem *)par->smem + vid_base * 0x1000;
+	info->screen_size = info->fix.smem_len - 2 * vid_base * 0x1000;
+
+	pmagbbfb_erase_cursor(info);
+	pmagbbfb_screen_setup(info);
+	pmagbbfb_osc_setup(info);
+
+	err = register_framebuffer(info);
+	if (err < 0) {
+		printk(KERN_ERR "%s: Cannot register framebuffer\n",
+		       dev_name(dev));
+		goto err_smem_map;
+	}
+
+	get_device(dev);
+
+	snprintf(freq0, sizeof(freq0), "%u.%03uMHz",
+		 par->osc0 / 1000, par->osc0 % 1000);
+	snprintf(freq1, sizeof(freq1), "%u.%03uMHz",
+		 par->osc1 / 1000, par->osc1 % 1000);
+
+	fb_info(info, "%s frame buffer device at %s\n",
+		info->fix.id, dev_name(dev));
+	fb_info(info, "Osc0: %s, Osc1: %s, Osc%u selected\n",
+		freq0, par->osc1 ? freq1 : "disabled", par->osc1 != 0);
+
+	return 0;
+
+
+err_smem_map:
+	iounmap(par->smem);
+
+err_mmio_map:
+	iounmap(par->mmio);
+
+err_resource:
+	release_mem_region(start, len);
+
+err_cmap:
+	fb_dealloc_cmap(&info->cmap);
+
+err_alloc:
+	framebuffer_release(info);
+	return err;
+}
+
+static int pmagbbfb_remove(struct device *dev)
+{
+	struct tc_dev *tdev = to_tc_dev(dev);
+	struct fb_info *info = dev_get_drvdata(dev);
+	struct pmagbbfb_par *par = info->par;
+	resource_size_t start, len;
+
+	put_device(dev);
+	unregister_framebuffer(info);
+	iounmap(par->smem);
+	iounmap(par->mmio);
+	start = tdev->resource.start;
+	len = tdev->resource.end - start + 1;
+	release_mem_region(start, len);
+	fb_dealloc_cmap(&info->cmap);
+	framebuffer_release(info);
+	return 0;
+}
+
+
+/*
+ * Initialize the framebuffer.
+ */
+static const struct tc_device_id pmagbbfb_tc_table[] = {
+	{ "DEC     ", "PMAGB-BA" },
+	{ }
+};
+MODULE_DEVICE_TABLE(tc, pmagbbfb_tc_table);
+
+static struct tc_driver pmagbbfb_driver = {
+	.id_table	= pmagbbfb_tc_table,
+	.driver		= {
+		.name	= "pmagbbfb",
+		.bus	= &tc_bus_type,
+		.probe	= pmagbbfb_probe,
+		.remove	= pmagbbfb_remove,
+	},
+};
+
+static int __init pmagbbfb_init(void)
+{
+#ifndef MODULE
+	if (fb_get_options("pmagbbfb", NULL))
+		return -ENXIO;
+#endif
+	return tc_register_driver(&pmagbbfb_driver);
+}
+
+static void __exit pmagbbfb_exit(void)
+{
+	tc_unregister_driver(&pmagbbfb_driver);
+}
+
+
+module_init(pmagbbfb_init);
+module_exit(pmagbbfb_exit);
+
+MODULE_LICENSE("GPL");