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, 395 insertions, 0 deletions

diff --git a/drivers/video/console/sticon.c b/drivers/video/console/sticon.c
new file mode 100644
index 000000000..6f58e6a9e
--- /dev/null
+++ b/drivers/video/console/sticon.c
@@ -0,0 +1,395 @@
+/*
+ *  linux/drivers/video/console/sticon.c - console driver using HP's STI firmware
+ *
+ *	Copyright (C) 2000 Philipp Rumpf <prumpf@tux.org>
+ *	Copyright (C) 2002-2020 Helge Deller <deller@gmx.de>
+ *
+ *  Based on linux/drivers/video/vgacon.c and linux/drivers/video/fbcon.c,
+ *  which were
+ *
+ *	Created 28 Sep 1997 by Geert Uytterhoeven
+ *	Rewritten by Martin Mares <mj@ucw.cz>, July 1998
+ *	Copyright (C) 1991, 1992  Linus Torvalds
+ *			    1995  Jay Estabrook
+ *	Copyright (C) 1995 Geert Uytterhoeven
+ *	Copyright (C) 1993 Bjoern Brauel
+ *			   Roman Hodek
+ *	Copyright (C) 1993 Hamish Macdonald
+ *			   Greg Harp
+ *	Copyright (C) 1994 David Carter [carter@compsci.bristol.ac.uk]
+ *
+ *	      with work by William Rucklidge (wjr@cs.cornell.edu)
+ *			   Geert Uytterhoeven
+ *			   Jes Sorensen (jds@kom.auc.dk)
+ *			   Martin Apel
+ *	      with work by Guenther Kelleter
+ *			   Martin Schaller
+ *			   Andreas Schwab
+ *			   Emmanuel Marty (core@ggi-project.org)
+ *			   Jakub Jelinek (jj@ultra.linux.cz)
+ *			   Martin Mares <mj@ucw.cz>
+ *
+ *  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/init.h>
+#include <linux/kernel.h>
+#include <linux/console.h>
+#include <linux/errno.h>
+#include <linux/vt_kern.h>
+#include <linux/kd.h>
+#include <linux/selection.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/font.h>
+#include <linux/crc32.h>
+#include <linux/fb.h>
+
+#include <asm/io.h>
+
+#include <video/sticore.h>
+
+/* switching to graphics mode */
+#define BLANK 0
+static int vga_is_gfx;
+
+#define STI_DEF_FONT	sticon_sti->font
+
+/* borrowed from fbcon.c */
+#define FNTREFCOUNT(fd)	(fd->refcount)
+#define FNTCRC(fd)	(fd->crc)
+static struct sti_cooked_font *font_data[MAX_NR_CONSOLES];
+
+/* this is the sti_struct used for this console */
+static struct sti_struct *sticon_sti;
+
+static const char *sticon_startup(void)
+{
+    return "STI console";
+}
+
+static void sticon_putcs(struct vc_data *conp, const u16 *s, unsigned int count,
+			 unsigned int ypos, unsigned int xpos)
+{
+    if (vga_is_gfx || console_blanked)
+	    return;
+
+    if (conp->vc_mode != KD_TEXT)
+    	    return;
+
+    while (count--) {
+	sti_putc(sticon_sti, scr_readw(s++), ypos, xpos++,
+		 font_data[conp->vc_num]);
+    }
+}
+
+static void sticon_cursor(struct vc_data *conp, bool enable)
+{
+    unsigned short car1;
+
+    /* no cursor update if screen is blanked */
+    if (vga_is_gfx || console_blanked)
+	return;
+
+    car1 = conp->vc_screenbuf[conp->state.x + conp->state.y * conp->vc_cols];
+    if (!enable) {
+	sti_putc(sticon_sti, car1, conp->state.y, conp->state.x,
+		 font_data[conp->vc_num]);
+	return;
+    }
+
+    switch (CUR_SIZE(conp->vc_cursor_type)) {
+    case CUR_UNDERLINE:
+    case CUR_LOWER_THIRD:
+    case CUR_LOWER_HALF:
+    case CUR_TWO_THIRDS:
+    case CUR_BLOCK:
+	sti_putc(sticon_sti, (car1 & 255) + (0 << 8) + (7 << 11),
+		 conp->state.y, conp->state.x, font_data[conp->vc_num]);
+	break;
+    }
+}
+
+static bool sticon_scroll(struct vc_data *conp, unsigned int t,
+		unsigned int b, enum con_scroll dir, unsigned int count)
+{
+    struct sti_struct *sti = sticon_sti;
+
+    if (vga_is_gfx)
+        return false;
+
+    sticon_cursor(conp, false);
+
+    switch (dir) {
+    case SM_UP:
+	sti_bmove(sti, t + count, 0, t, 0, b - t - count, conp->vc_cols,
+		  font_data[conp->vc_num]);
+	sti_clear(sti, b - count, 0, count, conp->vc_cols,
+		  conp->vc_video_erase_char, font_data[conp->vc_num]);
+	break;
+
+    case SM_DOWN:
+	sti_bmove(sti, t, 0, t + count, 0, b - t - count, conp->vc_cols,
+		  font_data[conp->vc_num]);
+	sti_clear(sti, t, 0, count, conp->vc_cols,
+		  conp->vc_video_erase_char, font_data[conp->vc_num]);
+	break;
+    }
+
+    return false;
+}
+
+static void sticon_set_def_font(int unit)
+{
+	if (font_data[unit] != STI_DEF_FONT) {
+		if (--FNTREFCOUNT(font_data[unit]) == 0) {
+			kfree(font_data[unit]->raw_ptr);
+			kfree(font_data[unit]);
+		}
+		font_data[unit] = STI_DEF_FONT;
+	}
+}
+
+static int sticon_set_font(struct vc_data *vc, const struct console_font *op,
+			   unsigned int vpitch)
+{
+	struct sti_struct *sti = sticon_sti;
+	int vc_cols, vc_rows, vc_old_cols, vc_old_rows;
+	int unit = vc->vc_num;
+	int w = op->width;
+	int h = op->height;
+	int size, i, bpc, pitch;
+	struct sti_rom_font *new_font;
+	struct sti_cooked_font *cooked_font;
+	unsigned char *data = op->data, *p;
+
+	if ((w < 6) || (h < 6) || (w > 32) || (h > 32) || (vpitch != 32)
+	    || (op->charcount != 256 && op->charcount != 512))
+		return -EINVAL;
+	pitch = ALIGN(w, 8) / 8;
+	bpc = pitch * h;
+	size = bpc * op->charcount;
+
+	new_font = kmalloc(sizeof(*new_font) + size, STI_LOWMEM);
+	if (!new_font)
+		return -ENOMEM;
+
+	new_font->first_char = 0;
+	new_font->last_char = op->charcount - 1;
+	new_font->width = w;
+	new_font->height = h;
+	new_font->font_type = STI_FONT_HPROMAN8;
+	new_font->bytes_per_char = bpc;
+	new_font->underline_height = 0;
+	new_font->underline_pos = 0;
+
+	cooked_font = kzalloc_obj(*cooked_font);
+	if (!cooked_font) {
+		kfree(new_font);
+		return -ENOMEM;
+	}
+	cooked_font->raw = new_font;
+	cooked_font->raw_ptr = new_font;
+	cooked_font->width = w;
+	cooked_font->height = h;
+	FNTREFCOUNT(cooked_font) = 0;	/* usage counter */
+
+	p = (unsigned char *) new_font;
+	p += sizeof(*new_font);
+	for (i = 0; i < op->charcount; i++) {
+		memcpy(p, data, bpc);
+		data += pitch*32;
+		p += bpc;
+	}
+	FNTCRC(cooked_font) = crc32(0, new_font, size + sizeof(*new_font));
+	sti_font_convert_bytemode(sti, cooked_font);
+	new_font = cooked_font->raw_ptr;
+
+	/* check if font is already used by other console */
+	for (i = 0; i < MAX_NR_CONSOLES; i++) {
+		if (font_data[i] != STI_DEF_FONT
+		    && (FNTCRC(font_data[i]) == FNTCRC(cooked_font))) {
+			kfree(new_font);
+			kfree(cooked_font);
+			/* current font is the same as the new one */
+			if (i == unit)
+				return 0;
+			cooked_font = font_data[i];
+			new_font = cooked_font->raw_ptr;
+			break;
+		}
+	}
+
+	/* clear screen with old font: we now may have less rows */
+	vc_old_rows = vc->vc_rows;
+	vc_old_cols = vc->vc_cols;
+	sti_clear(sticon_sti, 0, 0, vc_old_rows, vc_old_cols,
+		  vc->vc_video_erase_char, font_data[vc->vc_num]);
+
+	/* delete old font in case it is a user font */
+	sticon_set_def_font(unit);
+
+	FNTREFCOUNT(cooked_font)++;
+	font_data[unit] = cooked_font;
+
+	vc_cols = sti_onscreen_x(sti) / cooked_font->width;
+	vc_rows = sti_onscreen_y(sti) / cooked_font->height;
+	vc_resize(vc, vc_cols, vc_rows);
+
+	/* need to repaint screen if cols & rows are same as old font */
+	if (vc_cols == vc_old_cols && vc_rows == vc_old_rows)
+		update_screen(vc);
+
+	return 0;
+}
+
+static int sticon_font_default(struct vc_data *vc, struct console_font *op,
+			       const char *name)
+{
+	sticon_set_def_font(vc->vc_num);
+
+	return 0;
+}
+
+static int sticon_font_set(struct vc_data *vc, const struct console_font *font,
+			   unsigned int vpitch, unsigned int flags)
+{
+	return sticon_set_font(vc, font, vpitch);
+}
+
+static void sticon_init(struct vc_data *c, bool init)
+{
+    struct sti_struct *sti = sticon_sti;
+    int vc_cols, vc_rows;
+
+    sti_set(sti, 0, 0, sti_onscreen_y(sti), sti_onscreen_x(sti), 0);
+    vc_cols = sti_onscreen_x(sti) / sti->font->width;
+    vc_rows = sti_onscreen_y(sti) / sti->font->height;
+    c->vc_can_do_color = 1;
+
+    if (init) {
+	c->vc_cols = vc_cols;
+	c->vc_rows = vc_rows;
+    } else {
+	vc_resize(c, vc_cols, vc_rows);
+    }
+}
+
+static void sticon_deinit(struct vc_data *c)
+{
+    int i;
+
+    /* free memory used by user font */
+    for (i = 0; i < MAX_NR_CONSOLES; i++)
+	sticon_set_def_font(i);
+}
+
+static void sticon_clear(struct vc_data *conp, unsigned int sy, unsigned int sx,
+			 unsigned int width)
+{
+    sti_clear(sticon_sti, sy, sx, 1, width,
+	      conp->vc_video_erase_char, font_data[conp->vc_num]);
+}
+
+static bool sticon_switch(struct vc_data *conp)
+{
+    return true;	/* needs refreshing */
+}
+
+static bool sticon_blank(struct vc_data *c, enum vesa_blank_mode blank,
+			 bool mode_switch)
+{
+    if (blank == VESA_NO_BLANKING) {
+	if (mode_switch)
+	    vga_is_gfx = 0;
+	return true;
+    }
+    sti_clear(sticon_sti, 0, 0, c->vc_rows, c->vc_cols, BLANK,
+	      font_data[c->vc_num]);
+    if (mode_switch)
+	vga_is_gfx = 1;
+
+    return true;
+}
+
+static u8 sticon_build_attr(struct vc_data *conp, u8 color,
+			    enum vc_intensity intens,
+			    bool blink, bool underline, bool reverse,
+			    bool italic)
+{
+	u8 fg = color & 7;
+	u8 bg = (color & 0x70) >> 4;
+
+	if (reverse)
+		return (fg << 3) | bg;
+	else
+		return (bg << 3) | fg;
+}
+
+static void sticon_invert_region(struct vc_data *conp, u16 *p, int count)
+{
+    int col = 1; /* vga_can_do_color; */
+
+    while (count--) {
+	u16 a = scr_readw(p);
+
+	if (col)
+		a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
+	else
+		a = ((a & 0x0700) == 0x0100) ? 0x7000 : 0x7700;
+
+	scr_writew(a, p++);
+    }
+}
+
+static const struct consw sti_con = {
+	.owner			= THIS_MODULE,
+	.con_startup		= sticon_startup,
+	.con_init		= sticon_init,
+	.con_deinit		= sticon_deinit,
+	.con_clear		= sticon_clear,
+	.con_putcs		= sticon_putcs,
+	.con_cursor		= sticon_cursor,
+	.con_scroll		= sticon_scroll,
+	.con_switch		= sticon_switch,
+	.con_blank		= sticon_blank,
+	.con_font_set		= sticon_font_set,
+	.con_font_default	= sticon_font_default,
+	.con_build_attr		= sticon_build_attr,
+	.con_invert_region	= sticon_invert_region,
+};
+
+
+
+static int __init sticonsole_init(void)
+{
+    int err, i;
+
+    /* already initialized ? */
+    if (sticon_sti)
+	 return 0;
+
+    sticon_sti = sti_get_rom(0);
+    if (!sticon_sti)
+	return -ENODEV;
+
+    for (i = 0; i < MAX_NR_CONSOLES; i++)
+	font_data[i] = STI_DEF_FONT;
+
+    pr_info("sticon: Initializing STI text console on %s at [%s]\n",
+	sticon_sti->sti_data->inq_outptr.dev_name,
+	sticon_sti->pa_path);
+    console_lock();
+    err = do_take_over_console(&sti_con, 0, MAX_NR_CONSOLES - 1,
+		PAGE0->mem_cons.cl_class != CL_DUPLEX);
+    console_unlock();
+
+    return err;
+}
+
+module_init(sticonsole_init);
+MODULE_DESCRIPTION("HP STI console driver");
+MODULE_LICENSE("GPL");