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, 442 insertions, 0 deletions

diff --git a/drivers/mfd/ipaq-micro.c b/drivers/mfd/ipaq-micro.c
new file mode 100644
index 000000000..5146a6eb0
--- /dev/null
+++ b/drivers/mfd/ipaq-micro.c
@@ -0,0 +1,442 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Compaq iPAQ h3xxx Atmel microcontroller companion support
+ *
+ * This is an Atmel AT90LS8535 with a special flashed-in firmware that
+ * implements the special protocol used by this driver.
+ *
+ * based on previous kernel 2.4 version by Andrew Christian
+ * Author : Alessandro Gardich <gremlin@gremlin.it>
+ * Author : Dmitry Artamonow <mad_soft@inbox.ru>
+ * Author : Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pm.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/ipaq-micro.h>
+#include <linux/string.h>
+#include <linux/string_choices.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+
+#include <mach/hardware.h>
+
+static void ipaq_micro_trigger_tx(struct ipaq_micro *micro)
+{
+	struct ipaq_micro_txdev *tx = &micro->tx;
+	struct ipaq_micro_msg *msg = micro->msg;
+	int i, bp;
+	u8 checksum;
+	u32 val;
+
+	bp = 0;
+	tx->buf[bp++] = CHAR_SOF;
+
+	checksum = ((msg->id & 0x0f) << 4) | (msg->tx_len & 0x0f);
+	tx->buf[bp++] = checksum;
+
+	for (i = 0; i < msg->tx_len; i++) {
+		tx->buf[bp++] = msg->tx_data[i];
+		checksum += msg->tx_data[i];
+	}
+
+	tx->buf[bp++] = checksum;
+	tx->len = bp;
+	tx->index = 0;
+
+	/* Enable interrupt */
+	val = readl(micro->base + UTCR3);
+	val |= UTCR3_TIE;
+	writel(val, micro->base + UTCR3);
+}
+
+int ipaq_micro_tx_msg(struct ipaq_micro *micro, struct ipaq_micro_msg *msg)
+{
+	unsigned long flags;
+
+	dev_dbg(micro->dev, "TX msg: %02x, %d bytes\n", msg->id, msg->tx_len);
+
+	spin_lock_irqsave(&micro->lock, flags);
+	if (micro->msg) {
+		list_add_tail(&msg->node, &micro->queue);
+		spin_unlock_irqrestore(&micro->lock, flags);
+		return 0;
+	}
+	micro->msg = msg;
+	ipaq_micro_trigger_tx(micro);
+	spin_unlock_irqrestore(&micro->lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL(ipaq_micro_tx_msg);
+
+static void micro_rx_msg(struct ipaq_micro *micro, u8 id, int len, u8 *data)
+{
+	dev_dbg(micro->dev, "RX msg: %02x, %d bytes\n", id, len);
+
+	spin_lock(&micro->lock);
+	switch (id) {
+	case MSG_VERSION:
+	case MSG_EEPROM_READ:
+	case MSG_EEPROM_WRITE:
+	case MSG_BACKLIGHT:
+	case MSG_NOTIFY_LED:
+	case MSG_THERMAL_SENSOR:
+	case MSG_BATTERY:
+		/* Handle synchronous messages */
+		if (micro->msg && micro->msg->id == id) {
+			struct ipaq_micro_msg *msg = micro->msg;
+
+			memcpy(msg->rx_data, data, len);
+			msg->rx_len = len;
+			complete(&micro->msg->ack);
+			if (!list_empty(&micro->queue)) {
+				micro->msg = list_entry(micro->queue.next,
+							struct ipaq_micro_msg,
+							node);
+				list_del_init(&micro->msg->node);
+				ipaq_micro_trigger_tx(micro);
+			} else
+				micro->msg = NULL;
+			dev_dbg(micro->dev, "OK RX message 0x%02x\n", id);
+		} else {
+			dev_err(micro->dev,
+				"out of band RX message 0x%02x\n", id);
+			if (!micro->msg)
+				dev_info(micro->dev, "no message queued\n");
+			else
+				dev_info(micro->dev, "expected message %02x\n",
+					 micro->msg->id);
+		}
+		break;
+	case MSG_KEYBOARD:
+		if (micro->key)
+			micro->key(micro->key_data, len, data);
+		else
+			dev_dbg(micro->dev, "key message ignored, no handle\n");
+		break;
+	case MSG_TOUCHSCREEN:
+		if (micro->ts)
+			micro->ts(micro->ts_data, len, data);
+		else
+			dev_dbg(micro->dev, "touchscreen message ignored, no handle\n");
+		break;
+	default:
+		dev_err(micro->dev,
+			"unknown msg %d [%d] %*ph\n", id, len, len, data);
+		break;
+	}
+	spin_unlock(&micro->lock);
+}
+
+static void micro_process_char(struct ipaq_micro *micro, u8 ch)
+{
+	struct ipaq_micro_rxdev *rx = &micro->rx;
+
+	switch (rx->state) {
+	case STATE_SOF:	/* Looking for SOF */
+		if (ch == CHAR_SOF)
+			rx->state = STATE_ID; /* Next byte is the id and len */
+		break;
+	case STATE_ID: /* Looking for id and len byte */
+		rx->id = (ch & 0xf0) >> 4;
+		rx->len = (ch & 0x0f);
+		rx->index = 0;
+		rx->chksum = ch;
+		rx->state = (rx->len > 0) ? STATE_DATA : STATE_CHKSUM;
+		break;
+	case STATE_DATA: /* Looking for 'len' data bytes */
+		rx->chksum += ch;
+		rx->buf[rx->index] = ch;
+		if (++rx->index == rx->len)
+			rx->state = STATE_CHKSUM;
+		break;
+	case STATE_CHKSUM: /* Looking for the checksum */
+		if (ch == rx->chksum)
+			micro_rx_msg(micro, rx->id, rx->len, rx->buf);
+		rx->state = STATE_SOF;
+		break;
+	}
+}
+
+static void micro_rx_chars(struct ipaq_micro *micro)
+{
+	u32 status, ch;
+
+	while ((status = readl(micro->base + UTSR1)) & UTSR1_RNE) {
+		ch = readl(micro->base + UTDR);
+		if (status & UTSR1_PRE)
+			dev_err(micro->dev, "rx: parity error\n");
+		else if (status & UTSR1_FRE)
+			dev_err(micro->dev, "rx: framing error\n");
+		else if (status & UTSR1_ROR)
+			dev_err(micro->dev, "rx: overrun error\n");
+		micro_process_char(micro, ch);
+	}
+}
+
+static void ipaq_micro_get_version(struct ipaq_micro *micro)
+{
+	struct ipaq_micro_msg msg = {
+		.id = MSG_VERSION,
+	};
+
+	ipaq_micro_tx_msg_sync(micro, &msg);
+	if (msg.rx_len == 4) {
+		memcpy(micro->version, msg.rx_data, 4);
+		micro->version[4] = '\0';
+	} else if (msg.rx_len == 9) {
+		memcpy(micro->version, msg.rx_data, 4);
+		micro->version[4] = '\0';
+		/* Bytes 4-7 are "pack", byte 8 is "boot type" */
+	} else {
+		dev_err(micro->dev,
+			"illegal version message %d bytes\n", msg.rx_len);
+	}
+}
+
+static void ipaq_micro_eeprom_read(struct ipaq_micro *micro,
+				   u8 address, u8 len, u8 *data)
+{
+	struct ipaq_micro_msg msg = {
+		.id = MSG_EEPROM_READ,
+	};
+	u8 i;
+
+	for (i = 0; i < len; i++) {
+		msg.tx_data[0] = address + i;
+		msg.tx_data[1] = 1;
+		msg.tx_len = 2;
+		ipaq_micro_tx_msg_sync(micro, &msg);
+		memcpy(data + (i * 2), msg.rx_data, 2);
+	}
+}
+
+static char *ipaq_micro_str(u8 *wchar, u8 len)
+{
+	char retstr[256] = { 0 };
+	u8 i;
+
+	for (i = 0; i < len / 2; i++)
+		retstr[i] = wchar[i * 2];
+	return kstrdup(retstr, GFP_KERNEL);
+}
+
+static u16 ipaq_micro_to_u16(u8 *data)
+{
+	return data[1] << 8 | data[0];
+}
+
+static void __init ipaq_micro_eeprom_dump(struct ipaq_micro *micro)
+{
+	u8 dump[256];
+	char *str;
+
+	ipaq_micro_eeprom_read(micro, 0, 128, dump);
+	str = ipaq_micro_str(dump, 10);
+	if (str) {
+		dev_info(micro->dev, "HW version %s\n", str);
+		kfree(str);
+	}
+	str = ipaq_micro_str(dump+10, 40);
+	if (str) {
+		dev_info(micro->dev, "serial number: %s\n", str);
+		/* Feed the random pool with this */
+		add_device_randomness(str, strlen(str));
+		kfree(str);
+	}
+	str = ipaq_micro_str(dump+50, 20);
+	if (str) {
+		dev_info(micro->dev, "module ID: %s\n", str);
+		kfree(str);
+	}
+	str = ipaq_micro_str(dump+70, 10);
+	if (str) {
+		dev_info(micro->dev, "product revision: %s\n", str);
+		kfree(str);
+	}
+	dev_info(micro->dev, "product ID: %u\n", ipaq_micro_to_u16(dump+80));
+	dev_info(micro->dev, "frame rate: %u fps\n",
+		 ipaq_micro_to_u16(dump+82));
+	dev_info(micro->dev, "page mode: %u\n", ipaq_micro_to_u16(dump+84));
+	dev_info(micro->dev, "country ID: %u\n", ipaq_micro_to_u16(dump+86));
+	dev_info(micro->dev, "color display: %s\n",
+		 str_yes_no(ipaq_micro_to_u16(dump + 88)));
+	dev_info(micro->dev, "ROM size: %u MiB\n", ipaq_micro_to_u16(dump+90));
+	dev_info(micro->dev, "RAM size: %u KiB\n", ipaq_micro_to_u16(dump+92));
+	dev_info(micro->dev, "screen: %u x %u\n",
+		 ipaq_micro_to_u16(dump+94), ipaq_micro_to_u16(dump+96));
+}
+
+static void micro_tx_chars(struct ipaq_micro *micro)
+{
+	struct ipaq_micro_txdev *tx = &micro->tx;
+	u32 val;
+
+	while ((tx->index < tx->len) &&
+	       (readl(micro->base + UTSR1) & UTSR1_TNF)) {
+		writel(tx->buf[tx->index], micro->base + UTDR);
+		tx->index++;
+	}
+
+	/* Stop interrupts */
+	val = readl(micro->base + UTCR3);
+	val &= ~UTCR3_TIE;
+	writel(val, micro->base + UTCR3);
+}
+
+static void micro_reset_comm(struct ipaq_micro *micro)
+{
+	struct ipaq_micro_rxdev *rx = &micro->rx;
+	u32 val;
+
+	if (micro->msg)
+		complete(&micro->msg->ack);
+
+	/* Initialize Serial channel protocol frame */
+	rx->state = STATE_SOF;  /* Reset the state machine */
+
+	/* Set up interrupts */
+	writel(0x01, micro->sdlc + 0x0); /* Select UART mode */
+
+	/* Clean up CR3 */
+	writel(0x0, micro->base + UTCR3);
+
+	/* Format: 8N1 */
+	writel(UTCR0_8BitData | UTCR0_1StpBit, micro->base + UTCR0);
+
+	/* Baud rate: 115200 */
+	writel(0x0, micro->base + UTCR1);
+	writel(0x1, micro->base + UTCR2);
+
+	/* Clear SR0 */
+	writel(0xff, micro->base + UTSR0);
+
+	/* Enable RX int, disable TX int */
+	writel(UTCR3_TXE | UTCR3_RXE | UTCR3_RIE, micro->base + UTCR3);
+	val = readl(micro->base + UTCR3);
+	val &= ~UTCR3_TIE;
+	writel(val, micro->base + UTCR3);
+}
+
+static irqreturn_t micro_serial_isr(int irq, void *dev_id)
+{
+	struct ipaq_micro *micro = dev_id;
+	struct ipaq_micro_txdev *tx = &micro->tx;
+	u32 status;
+
+	status = readl(micro->base + UTSR0);
+	do {
+		if (status & (UTSR0_RID | UTSR0_RFS)) {
+			if (status & UTSR0_RID)
+				/* Clear the Receiver IDLE bit */
+				writel(UTSR0_RID, micro->base + UTSR0);
+			micro_rx_chars(micro);
+		}
+
+		/* Clear break bits */
+		if (status & (UTSR0_RBB | UTSR0_REB))
+			writel(status & (UTSR0_RBB | UTSR0_REB),
+			       micro->base + UTSR0);
+
+		if (status & UTSR0_TFS)
+			micro_tx_chars(micro);
+
+		status = readl(micro->base + UTSR0);
+
+	} while (((tx->index < tx->len) && (status & UTSR0_TFS)) ||
+		 (status & (UTSR0_RFS | UTSR0_RID)));
+
+	return IRQ_HANDLED;
+}
+
+static const struct mfd_cell micro_cells[] = {
+	{ .name = "ipaq-micro-backlight", },
+	{ .name = "ipaq-micro-battery", },
+	{ .name = "ipaq-micro-keys", },
+	{ .name = "ipaq-micro-ts", },
+	{ .name = "ipaq-micro-leds", },
+};
+
+static int __maybe_unused micro_resume(struct device *dev)
+{
+	struct ipaq_micro *micro = dev_get_drvdata(dev);
+
+	micro_reset_comm(micro);
+	mdelay(10);
+
+	return 0;
+}
+
+static int __init micro_probe(struct platform_device *pdev)
+{
+	struct ipaq_micro *micro;
+	int ret;
+	int irq;
+
+	micro = devm_kzalloc(&pdev->dev, sizeof(*micro), GFP_KERNEL);
+	if (!micro)
+		return -ENOMEM;
+
+	micro->dev = &pdev->dev;
+
+	micro->base = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
+	if (IS_ERR(micro->base))
+		return PTR_ERR(micro->base);
+
+	micro->sdlc = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(micro->sdlc))
+		return PTR_ERR(micro->sdlc);
+
+	micro_reset_comm(micro);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -EINVAL;
+	ret = devm_request_irq(&pdev->dev, irq, micro_serial_isr,
+			       IRQF_SHARED, "ipaq-micro",
+			       micro);
+	if (ret) {
+		dev_err(&pdev->dev, "unable to grab serial port IRQ\n");
+		return ret;
+	} else
+		dev_info(&pdev->dev, "grabbed serial port IRQ\n");
+
+	spin_lock_init(&micro->lock);
+	INIT_LIST_HEAD(&micro->queue);
+	platform_set_drvdata(pdev, micro);
+
+	ret = mfd_add_devices(&pdev->dev, pdev->id, micro_cells,
+			      ARRAY_SIZE(micro_cells), NULL, 0, NULL);
+	if (ret) {
+		dev_err(&pdev->dev, "error adding MFD cells");
+		return ret;
+	}
+
+	/* Check version */
+	ipaq_micro_get_version(micro);
+	dev_info(&pdev->dev, "Atmel micro ASIC version %s\n", micro->version);
+	ipaq_micro_eeprom_dump(micro);
+
+	return 0;
+}
+
+static const struct dev_pm_ops micro_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(NULL, micro_resume)
+};
+
+static struct platform_driver micro_device_driver = {
+	.driver   = {
+		.name	= "ipaq-h3xxx-micro",
+		.pm	= &micro_dev_pm_ops,
+		.suppress_bind_attrs = true,
+	},
+};
+builtin_platform_driver_probe(micro_device_driver, micro_probe);