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

5 files changed, 425 insertions, 0 deletions

diff --git a/drivers/reset/sti/Kconfig b/drivers/reset/sti/Kconfig
new file mode 100644
index 000000000..0b599f7cf
--- /dev/null
+++ b/drivers/reset/sti/Kconfig
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-only
+if ARCH_STI || COMPILE_TEST
+
+config STIH407_RESET
+	bool "STIH407 Reset Driver" if COMPILE_TEST
+
+endif
diff --git a/drivers/reset/sti/Makefile b/drivers/reset/sti/Makefile
new file mode 100644
index 000000000..5e833496c
--- /dev/null
+++ b/drivers/reset/sti/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_STIH407_RESET) += reset-stih407.o reset-syscfg.o
diff --git a/drivers/reset/sti/reset-stih407.c b/drivers/reset/sti/reset-stih407.c
new file mode 100644
index 000000000..c3bf9a918
--- /dev/null
+++ b/drivers/reset/sti/reset-stih407.c
@@ -0,0 +1,159 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2014 STMicroelectronics (R&D) Limited
+ * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
+ */
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/platform_device.h>
+#include <dt-bindings/reset/stih407-resets.h>
+#include "reset-syscfg.h"
+
+/* STiH407 Peripheral powerdown definitions. */
+static const char stih407_core[] = "st,stih407-core-syscfg";
+static const char stih407_sbc_reg[] = "st,stih407-sbc-reg-syscfg";
+static const char stih407_lpm[] = "st,stih407-lpm-syscfg";
+
+#define STIH407_PDN_0(_bit) \
+	_SYSCFG_RST_CH(stih407_core, SYSCFG_5000, _bit, SYSSTAT_5500, _bit)
+#define STIH407_PDN_1(_bit) \
+	_SYSCFG_RST_CH(stih407_core, SYSCFG_5001, _bit, SYSSTAT_5501, _bit)
+#define STIH407_PDN_ETH(_bit, _stat) \
+	_SYSCFG_RST_CH(stih407_sbc_reg, SYSCFG_4032, _bit, SYSSTAT_4520, _stat)
+
+/* Powerdown requests control 0 */
+#define SYSCFG_5000	0x0
+#define SYSSTAT_5500	0x7d0
+/* Powerdown requests control 1 (High Speed Links) */
+#define SYSCFG_5001	0x4
+#define SYSSTAT_5501	0x7d4
+
+/* Ethernet powerdown/status/reset */
+#define SYSCFG_4032	0x80
+#define SYSSTAT_4520	0x820
+#define SYSCFG_4002	0x8
+
+static const struct syscfg_reset_channel_data stih407_powerdowns[] = {
+	[STIH407_EMISS_POWERDOWN] = STIH407_PDN_0(1),
+	[STIH407_NAND_POWERDOWN] = STIH407_PDN_0(0),
+	[STIH407_USB3_POWERDOWN] = STIH407_PDN_1(6),
+	[STIH407_USB2_PORT1_POWERDOWN] = STIH407_PDN_1(5),
+	[STIH407_USB2_PORT0_POWERDOWN] = STIH407_PDN_1(4),
+	[STIH407_PCIE1_POWERDOWN] = STIH407_PDN_1(3),
+	[STIH407_PCIE0_POWERDOWN] = STIH407_PDN_1(2),
+	[STIH407_SATA1_POWERDOWN] = STIH407_PDN_1(1),
+	[STIH407_SATA0_POWERDOWN] = STIH407_PDN_1(0),
+	[STIH407_ETH1_POWERDOWN] = STIH407_PDN_ETH(0, 2),
+};
+
+/* Reset Generator control 0/1 */
+#define SYSCFG_5128	0x200
+#define SYSCFG_5131	0x20c
+#define SYSCFG_5132	0x210
+
+#define LPM_SYSCFG_1	0x4	/* Softreset IRB & SBC UART */
+
+#define STIH407_SRST_CORE(_reg, _bit) \
+	_SYSCFG_RST_CH_NO_ACK(stih407_core, _reg, _bit)
+
+#define STIH407_SRST_SBC(_reg, _bit) \
+	_SYSCFG_RST_CH_NO_ACK(stih407_sbc_reg, _reg, _bit)
+
+#define STIH407_SRST_LPM(_reg, _bit) \
+	_SYSCFG_RST_CH_NO_ACK(stih407_lpm, _reg, _bit)
+
+static const struct syscfg_reset_channel_data stih407_softresets[] = {
+	[STIH407_ETH1_SOFTRESET] = STIH407_SRST_SBC(SYSCFG_4002, 4),
+	[STIH407_MMC1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 3),
+	[STIH407_USB2_PORT0_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 28),
+	[STIH407_USB2_PORT1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 29),
+	[STIH407_PICOPHY_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 30),
+	[STIH407_IRB_SOFTRESET] = STIH407_SRST_LPM(LPM_SYSCFG_1, 6),
+	[STIH407_PCIE0_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 6),
+	[STIH407_PCIE1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 15),
+	[STIH407_SATA0_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 7),
+	[STIH407_SATA1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 16),
+	[STIH407_MIPHY0_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 4),
+	[STIH407_MIPHY1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 13),
+	[STIH407_MIPHY2_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 22),
+	[STIH407_SATA0_PWR_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 5),
+	[STIH407_SATA1_PWR_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 14),
+	[STIH407_DELTA_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 3),
+	[STIH407_BLITTER_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 10),
+	[STIH407_HDTVOUT_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 11),
+	[STIH407_HDQVDP_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 12),
+	[STIH407_VDP_AUX_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 14),
+	[STIH407_COMPO_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 15),
+	[STIH407_HDMI_TX_PHY_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 21),
+	[STIH407_JPEG_DEC_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 23),
+	[STIH407_VP8_DEC_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 24),
+	[STIH407_GPU_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 30),
+	[STIH407_HVA_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 0),
+	[STIH407_ERAM_HVA_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5132, 1),
+	[STIH407_LPM_SOFTRESET] = STIH407_SRST_SBC(SYSCFG_4002, 2),
+	[STIH407_KEYSCAN_SOFTRESET] = STIH407_SRST_LPM(LPM_SYSCFG_1, 8),
+	[STIH407_ST231_AUD_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 26),
+	[STIH407_ST231_DMU_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 27),
+	[STIH407_ST231_GP0_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5131, 28),
+	[STIH407_ST231_GP1_SOFTRESET] = STIH407_SRST_CORE(SYSCFG_5128, 2),
+};
+
+/* PicoPHY reset/control */
+#define SYSCFG_5061	0x0f4
+
+static const struct syscfg_reset_channel_data stih407_picophyresets[] = {
+	[STIH407_PICOPHY0_RESET] = STIH407_SRST_CORE(SYSCFG_5061, 5),
+	[STIH407_PICOPHY1_RESET] = STIH407_SRST_CORE(SYSCFG_5061, 6),
+	[STIH407_PICOPHY2_RESET] = STIH407_SRST_CORE(SYSCFG_5061, 7),
+};
+
+static const struct syscfg_reset_controller_data stih407_powerdown_controller = {
+	.wait_for_ack = true,
+	.nr_channels = ARRAY_SIZE(stih407_powerdowns),
+	.channels = stih407_powerdowns,
+};
+
+static const struct syscfg_reset_controller_data stih407_softreset_controller = {
+	.wait_for_ack = false,
+	.active_low = true,
+	.nr_channels = ARRAY_SIZE(stih407_softresets),
+	.channels = stih407_softresets,
+};
+
+static const struct syscfg_reset_controller_data stih407_picophyreset_controller = {
+	.wait_for_ack = false,
+	.nr_channels = ARRAY_SIZE(stih407_picophyresets),
+	.channels = stih407_picophyresets,
+};
+
+static const struct of_device_id stih407_reset_match[] = {
+	{
+		.compatible = "st,stih407-powerdown",
+		.data = &stih407_powerdown_controller,
+	},
+	{
+		.compatible = "st,stih407-softreset",
+		.data = &stih407_softreset_controller,
+	},
+	{
+		.compatible = "st,stih407-picophyreset",
+		.data = &stih407_picophyreset_controller,
+	},
+	{ /* sentinel */ },
+};
+
+static struct platform_driver stih407_reset_driver = {
+	.probe = syscfg_reset_probe,
+	.driver = {
+		.name = "reset-stih407",
+		.of_match_table = stih407_reset_match,
+	},
+};
+
+static int __init stih407_reset_init(void)
+{
+	return platform_driver_register(&stih407_reset_driver);
+}
+
+arch_initcall(stih407_reset_init);
diff --git a/drivers/reset/sti/reset-syscfg.c b/drivers/reset/sti/reset-syscfg.c
new file mode 100644
index 000000000..38f78d78f
--- /dev/null
+++ b/drivers/reset/sti/reset-syscfg.c
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2013 STMicroelectronics Limited
+ * Author: Stephen Gallimore <stephen.gallimore@st.com>
+ *
+ * Inspired by mach-imx/src.c
+ */
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <linux/types.h>
+#include <linux/of.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
+
+#include "reset-syscfg.h"
+
+/**
+ * struct syscfg_reset_channel - Reset channel regmap configuration
+ *
+ * @reset: regmap field for the channel's reset bit.
+ * @ack: regmap field for the channel's ack bit (optional).
+ */
+struct syscfg_reset_channel {
+	struct regmap_field *reset;
+	struct regmap_field *ack;
+};
+
+/**
+ * struct syscfg_reset_controller - A reset controller which groups together
+ * a set of related reset bits, which may be located in different system
+ * configuration registers.
+ *
+ * @rst: base reset controller structure.
+ * @active_low: are the resets in this controller active low, i.e. clearing
+ *              the reset bit puts the hardware into reset.
+ * @channels: An array of reset channels for this controller.
+ */
+struct syscfg_reset_controller {
+	struct reset_controller_dev rst;
+	bool active_low;
+	struct syscfg_reset_channel channels[];
+};
+
+#define to_syscfg_reset_controller(_rst) \
+	container_of(_rst, struct syscfg_reset_controller, rst)
+
+static int syscfg_reset_program_hw(struct reset_controller_dev *rcdev,
+				   unsigned long idx, int assert)
+{
+	struct syscfg_reset_controller *rst = to_syscfg_reset_controller(rcdev);
+	const struct syscfg_reset_channel *ch;
+	u32 ctrl_val = rst->active_low ? !assert : !!assert;
+	int err;
+
+	if (idx >= rcdev->nr_resets)
+		return -EINVAL;
+
+	ch = &rst->channels[idx];
+
+	err = regmap_field_write(ch->reset, ctrl_val);
+	if (err)
+		return err;
+
+	if (ch->ack) {
+		u32 ack_val;
+
+		err = regmap_field_read_poll_timeout(ch->ack, ack_val, (ack_val == ctrl_val),
+						     100, USEC_PER_SEC);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
+static int syscfg_reset_assert(struct reset_controller_dev *rcdev,
+			       unsigned long idx)
+{
+	return syscfg_reset_program_hw(rcdev, idx, true);
+}
+
+static int syscfg_reset_deassert(struct reset_controller_dev *rcdev,
+				 unsigned long idx)
+{
+	return syscfg_reset_program_hw(rcdev, idx, false);
+}
+
+static int syscfg_reset_dev(struct reset_controller_dev *rcdev,
+			    unsigned long idx)
+{
+	int err;
+
+	err = syscfg_reset_assert(rcdev, idx);
+	if (err)
+		return err;
+
+	return syscfg_reset_deassert(rcdev, idx);
+}
+
+static int syscfg_reset_status(struct reset_controller_dev *rcdev,
+			       unsigned long idx)
+{
+	struct syscfg_reset_controller *rst = to_syscfg_reset_controller(rcdev);
+	const struct syscfg_reset_channel *ch;
+	u32 ret_val = 0;
+	int err;
+
+	if (idx >= rcdev->nr_resets)
+		return -EINVAL;
+
+	ch = &rst->channels[idx];
+	if (ch->ack)
+		err = regmap_field_read(ch->ack, &ret_val);
+	else
+		err = regmap_field_read(ch->reset, &ret_val);
+	if (err)
+		return err;
+
+	return rst->active_low ? !ret_val : !!ret_val;
+}
+
+static const struct reset_control_ops syscfg_reset_ops = {
+	.reset    = syscfg_reset_dev,
+	.assert   = syscfg_reset_assert,
+	.deassert = syscfg_reset_deassert,
+	.status   = syscfg_reset_status,
+};
+
+static int syscfg_reset_controller_register(struct device *dev,
+				const struct syscfg_reset_controller_data *data)
+{
+	struct syscfg_reset_controller *rc;
+	int i, err;
+
+	rc = devm_kzalloc(dev, struct_size(rc, channels, data->nr_channels), GFP_KERNEL);
+	if (!rc)
+		return -ENOMEM;
+
+	rc->rst.ops = &syscfg_reset_ops;
+	rc->rst.of_node = dev->of_node;
+	rc->rst.nr_resets = data->nr_channels;
+	rc->active_low = data->active_low;
+
+	for (i = 0; i < data->nr_channels; i++) {
+		struct regmap *map;
+		struct regmap_field *f;
+		const char *compatible = data->channels[i].compatible;
+
+		map = syscon_regmap_lookup_by_compatible(compatible);
+		if (IS_ERR(map))
+			return PTR_ERR(map);
+
+		f = devm_regmap_field_alloc(dev, map, data->channels[i].reset);
+		if (IS_ERR(f))
+			return PTR_ERR(f);
+
+		rc->channels[i].reset = f;
+
+		if (!data->wait_for_ack)
+			continue;
+
+		f = devm_regmap_field_alloc(dev, map, data->channels[i].ack);
+		if (IS_ERR(f))
+			return PTR_ERR(f);
+
+		rc->channels[i].ack = f;
+	}
+
+	err = reset_controller_register(&rc->rst);
+	if (!err)
+		dev_info(dev, "registered\n");
+
+	return err;
+}
+
+int syscfg_reset_probe(struct platform_device *pdev)
+{
+	struct device *dev = pdev ? &pdev->dev : NULL;
+	const void *data;
+
+	if (!dev || !dev->driver)
+		return -ENODEV;
+
+	data = device_get_match_data(&pdev->dev);
+	if (!data)
+		return -EINVAL;
+
+	return syscfg_reset_controller_register(dev, data);
+}
diff --git a/drivers/reset/sti/reset-syscfg.h b/drivers/reset/sti/reset-syscfg.h
new file mode 100644
index 000000000..4e3e69de1
--- /dev/null
+++ b/drivers/reset/sti/reset-syscfg.h
@@ -0,0 +1,65 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Copyright (C) 2013 STMicroelectronics (R&D) Limited
+ * Author: Stephen Gallimore <stephen.gallimore@st.com>
+ */
+#ifndef __STI_RESET_SYSCFG_H
+#define __STI_RESET_SYSCFG_H
+
+#include <linux/device.h>
+#include <linux/regmap.h>
+#include <linux/reset-controller.h>
+
+/**
+ * Reset channel description for a system configuration register based
+ * reset controller.
+ *
+ * @compatible: Compatible string of the syscon regmap containing this
+ *              channel's control and ack (status) bits.
+ * @reset: Regmap field description of the channel's reset bit.
+ * @ack: Regmap field description of the channel's acknowledge bit.
+ */
+struct syscfg_reset_channel_data {
+	const char *compatible;
+	struct reg_field reset;
+	struct reg_field ack;
+};
+
+#define _SYSCFG_RST_CH(_c, _rr, _rb, _ar, _ab)		\
+	{ .compatible	= _c,				\
+	  .reset	= REG_FIELD(_rr, _rb, _rb),	\
+	  .ack		= REG_FIELD(_ar, _ab, _ab), }
+
+#define _SYSCFG_RST_CH_NO_ACK(_c, _rr, _rb)		\
+	{ .compatible	= _c,			\
+	  .reset	= REG_FIELD(_rr, _rb, _rb), }
+
+/**
+ * Description of a system configuration register based reset controller.
+ *
+ * @wait_for_ack: The controller will wait for reset assert and de-assert to
+ *                be "ack'd" in a channel's ack field.
+ * @active_low: Are the resets in this controller active low, i.e. clearing
+ *              the reset bit puts the hardware into reset.
+ * @nr_channels: The number of reset channels in this controller.
+ * @channels: An array of reset channel descriptions.
+ */
+struct syscfg_reset_controller_data {
+	bool wait_for_ack;
+	bool active_low;
+	int nr_channels;
+	const struct syscfg_reset_channel_data *channels;
+};
+
+/**
+ * syscfg_reset_probe(): platform device probe function used by syscfg
+ *                       reset controller drivers. This registers a reset
+ *                       controller configured by the OF match data for
+ *                       the compatible device which should be of type
+ *                       "struct syscfg_reset_controller_data".
+ *
+ * @pdev: platform device
+ */
+int syscfg_reset_probe(struct platform_device *pdev);
+
+#endif /* __STI_RESET_SYSCFG_H */