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

3 files changed, 300 insertions, 0 deletions

diff --git a/drivers/phy/canaan/Kconfig b/drivers/phy/canaan/Kconfig
new file mode 100644
index 000000000..1ff883184
--- /dev/null
+++ b/drivers/phy/canaan/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Phy drivers for Canaan platforms
+#
+config PHY_CANAAN_USB
+	tristate "Canaan USB2 PHY Driver"
+	depends on (ARCH_CANAAN || COMPILE_TEST) && OF
+	select GENERIC_PHY
+	help
+	Enable this driver to support the USB 2.0 PHY controller
+	on Canaan K230 RISC-V SoCs. This PHY controller
+	provides physical layer functionality for USB 2.0 devices.
+	If you have a Canaan K230 board and need USB 2.0 support,
+	say Y or M here.
diff --git a/drivers/phy/canaan/Makefile b/drivers/phy/canaan/Makefile
new file mode 100644
index 000000000..d73857ba2
--- /dev/null
+++ b/drivers/phy/canaan/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_PHY_CANAAN_USB)		+= phy-k230-usb.o
diff --git a/drivers/phy/canaan/phy-k230-usb.c b/drivers/phy/canaan/phy-k230-usb.c
new file mode 100644
index 000000000..52dad35fc
--- /dev/null
+++ b/drivers/phy/canaan/phy-k230-usb.c
@@ -0,0 +1,284 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Canaan usb PHY driver
+ *
+ * Copyright (C) 2026 Jiayu Du <jiayu.riscv@isrc.iscas.ac.cn>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+
+#define MAX_PHYS		2
+
+/* Register offsets within the HiSysConfig system controller */
+#define K230_USB0_TEST_REG_BASE     0x70
+#define K230_USB0_CTL_REG_BASE      0xb0
+#define K230_USB1_TEST_REG_BASE     0x90
+#define K230_USB1_CTL_REG_BASE      0xb8
+
+/* Relative offsets within each PHY's control/test block */
+#define CTL0_OFFSET		0x00
+#define CTL1_OFFSET		0x04
+#define TEST_CTL3_OFFSET	0x0c
+
+/* Bit definitions for TEST_CTL3 */
+#define USB_IDPULLUP0		BIT(4)
+#define USB_DMPULLDOWN0		BIT(8)
+#define USB_DPPULLDOWN0		BIT(9)
+
+/* USB control register 0 in HiSysConfig system controller */
+/* PLL Integral Path Tune */
+#define USB_CTL0_PLLITUNE_MASK		GENMASK(23, 22)
+
+/* PLL Proportional Path Tune */
+#define USB_CTL0_PLLPTUNE_MASK		GENMASK(21, 18)
+
+/* PLL Bandwidth Adjustment */
+#define USB_CTL0_PLLBTUNE_MASK		GENMASK(17, 17)
+
+/* VReg18 Bypass Control */
+#define USB_CTL0_VREGBYPASS_MASK	GENMASK(16, 16)
+
+/* Retention Mode Enable */
+#define USB_CTL0_RETENABLEN_MASK	GENMASK(15, 15)
+
+/* Reserved Request Input */
+#define USB_CTL0_RESREQIN_MASK		GENMASK(14, 14)
+
+/* External VBUS Valid Select */
+#define USB_CTL0_VBUSVLDEXTSEL0_MASK	GENMASK(13, 13)
+
+/* OTG Block Disable Control */
+#define USB_CTL0_OTGDISABLE0_MASK	GENMASK(12, 12)
+
+/* Drive VBUS Enable */
+#define USB_CTL0_DRVVBUS0_MASK		GENMASK(11, 11)
+
+/* Autoresume Mode Enable */
+#define USB_CTL0_AUTORSMENB0_MASK	GENMASK(10, 10)
+
+/* HS Transceiver Asynchronous Control */
+#define USB_CTL0_HSXCVREXTCTL0_MASK	GENMASK(9, 9)
+
+/* USB 1.1 Transmit Data */
+#define USB_CTL0_FSDATAEXT0_MASK	GENMASK(8, 8)
+
+/* USB 1.1 SE0 Generation */
+#define USB_CTL0_FSSE0EXT0_MASK		GENMASK(7, 7)
+
+/* USB 1.1 Data Enable */
+#define USB_CTL0_TXENABLEN0_MASK	GENMASK(6, 6)
+
+/* Disconnect Threshold */
+#define USB_CTL0_COMPDISTUNE0_MASK	GENMASK(5, 3)
+
+/* Squelch Threshold */
+#define USB_CTL0_SQRXTUNE0_MASK		GENMASK(2, 0)
+
+/* USB control register 1 in HiSysConfig system controller */
+/* Data Detect Voltage */
+#define USB_CTL1_VDATREFTUNE0_MASK	GENMASK(23, 22)
+
+/* VBUS Valid Threshold */
+#define USB_CTL1_OTGTUNE0_MASK		GENMASK(21, 19)
+
+/* Transmitter High-Speed Crossover */
+#define USB_CTL1_TXHSXVTUNE0_MASK	GENMASK(18, 17)
+
+/* FS/LS Source Impedance */
+#define USB_CTL1_TXFSLSTUNE0_MASK	GENMASK(16, 13)
+
+/* HS DC Voltage Level */
+#define USB_CTL1_TXVREFTUNE0_MASK	GENMASK(12, 9)
+
+/* HS Transmitter Rise/Fall Time */
+#define USB_CTL1_TXRISETUNE0_MASK	GENMASK(8, 7)
+
+/* USB Source Impedance */
+#define USB_CTL1_TXRESTUNE0_MASK	GENMASK(6, 5)
+
+/* HS Transmitter Pre-Emphasis Current Control */
+#define USB_CTL1_TXPREEMPAMPTUNE0_MASK	GENMASK(4, 3)
+
+/* HS Transmitter Pre-Emphasis Duration Control */
+#define USB_CTL1_TXPREEMPPULSETUNE0_MASK	GENMASK(2, 2)
+
+/* charging detection */
+#define USB_CTL1_CHRGSRCPUENB0_MASK	GENMASK(1, 0)
+
+#define K230_PHY_CTL0_VAL \
+( \
+	FIELD_PREP(USB_CTL0_PLLITUNE_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_PLLPTUNE_MASK, 0xc) | \
+	FIELD_PREP(USB_CTL0_PLLBTUNE_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL0_VREGBYPASS_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL0_RETENABLEN_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL0_RESREQIN_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_VBUSVLDEXTSEL0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_OTGDISABLE0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_DRVVBUS0_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL0_AUTORSMENB0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_HSXCVREXTCTL0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_FSDATAEXT0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_FSSE0EXT0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_TXENABLEN0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL0_COMPDISTUNE0_MASK, 0x3) | \
+	FIELD_PREP(USB_CTL0_SQRXTUNE0_MASK, 0x3) \
+)
+
+#define K230_PHY_CTL1_VAL \
+( \
+	FIELD_PREP(USB_CTL1_VDATREFTUNE0_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL1_OTGTUNE0_MASK, 0x3) | \
+	FIELD_PREP(USB_CTL1_TXHSXVTUNE0_MASK, 0x3) | \
+	FIELD_PREP(USB_CTL1_TXFSLSTUNE0_MASK, 0x3) | \
+	FIELD_PREP(USB_CTL1_TXVREFTUNE0_MASK, 0x3) | \
+	FIELD_PREP(USB_CTL1_TXRISETUNE0_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL1_TXRESTUNE0_MASK, 0x1) | \
+	FIELD_PREP(USB_CTL1_TXPREEMPAMPTUNE0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL1_TXPREEMPPULSETUNE0_MASK, 0x0) | \
+	FIELD_PREP(USB_CTL1_CHRGSRCPUENB0_MASK, 0x0) \
+)
+
+struct k230_usb_phy_instance {
+	struct k230_usb_phy_global *global;
+	struct phy *phy;
+	u32 test_offset;
+	u32 ctl_offset;
+	int index;
+};
+
+struct k230_usb_phy_global {
+	struct k230_usb_phy_instance phys[MAX_PHYS];
+	void __iomem *base;
+};
+
+static int k230_usb_phy_power_on(struct phy *phy)
+{
+	struct k230_usb_phy_instance *inst = phy_get_drvdata(phy);
+	struct k230_usb_phy_global *global = inst->global;
+	void __iomem *base = global->base;
+	u32 val;
+
+	/* Apply recommended settings */
+	writel(K230_PHY_CTL0_VAL, base + inst->ctl_offset + CTL0_OFFSET);
+	writel(K230_PHY_CTL1_VAL, base + inst->ctl_offset + CTL1_OFFSET);
+
+	/* Configure test register (pull-ups/pull-downs) */
+	val = readl(base + inst->test_offset + TEST_CTL3_OFFSET);
+	val |= USB_IDPULLUP0;
+
+	if (inst->index == 1)
+		val |= (USB_DMPULLDOWN0 | USB_DPPULLDOWN0);
+	else
+		val &= ~(USB_DMPULLDOWN0 | USB_DPPULLDOWN0);
+
+	writel(val, base + inst->test_offset + TEST_CTL3_OFFSET);
+
+	return 0;
+}
+
+static int k230_usb_phy_power_off(struct phy *phy)
+{
+	struct k230_usb_phy_instance *inst = phy_get_drvdata(phy);
+	struct k230_usb_phy_global *global = inst->global;
+	void __iomem *base = global->base;
+	u32 val;
+
+	val = readl(base + inst->test_offset + TEST_CTL3_OFFSET);
+	val &= ~(USB_DMPULLDOWN0 | USB_DPPULLDOWN0);
+	writel(val, base + inst->test_offset + TEST_CTL3_OFFSET);
+
+	return 0;
+}
+
+static const struct phy_ops k230_usb_phy_ops = {
+	.power_on = k230_usb_phy_power_on,
+	.power_off = k230_usb_phy_power_off,
+	.owner = THIS_MODULE,
+};
+
+static struct phy *k230_usb_phy_xlate(struct device *dev,
+				      const struct of_phandle_args *args)
+{
+	struct k230_usb_phy_global *global = dev_get_drvdata(dev);
+	unsigned int idx = args->args[0];
+
+	if (idx >= MAX_PHYS)
+		return ERR_PTR(-EINVAL);
+
+	return global->phys[idx].phy;
+}
+
+static int k230_usb_phy_probe(struct platform_device *pdev)
+{
+	struct k230_usb_phy_global *global;
+	struct device *dev = &pdev->dev;
+	struct phy_provider *provider;
+	int i;
+
+	global = devm_kzalloc(dev, sizeof(*global), GFP_KERNEL);
+	if (!global)
+		return -ENOMEM;
+	dev_set_drvdata(dev, global);
+
+	global->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(global->base))
+		return dev_err_probe(dev, PTR_ERR(global->base),
+				     "failed to map registers\n");
+
+	static const struct {
+		u32 test_offset;
+		u32 ctl_offset;
+	} phy_reg_info[MAX_PHYS] = {
+		[0] = { K230_USB0_TEST_REG_BASE, K230_USB0_CTL_REG_BASE },
+		[1] = { K230_USB1_TEST_REG_BASE, K230_USB1_CTL_REG_BASE },
+	};
+
+	for (i = 0; i < MAX_PHYS; i++) {
+		struct k230_usb_phy_instance *inst = &global->phys[i];
+		struct phy *phy;
+
+		inst->global = global;
+		inst->index = i;
+		inst->test_offset = phy_reg_info[i].test_offset;
+		inst->ctl_offset  = phy_reg_info[i].ctl_offset;
+
+		phy = devm_phy_create(dev, NULL, &k230_usb_phy_ops);
+		if (IS_ERR(phy)) {
+			dev_err(dev, "failed to create phy%d\n", i);
+			return PTR_ERR(phy);
+		}
+
+		phy_set_drvdata(phy, inst);
+		inst->phy = phy;
+	}
+
+	provider = devm_of_phy_provider_register(dev, k230_usb_phy_xlate);
+	if (IS_ERR(provider))
+		return PTR_ERR(provider);
+
+	return 0;
+}
+
+static const struct of_device_id k230_usb_phy_of_match[] = {
+	{ .compatible = "canaan,k230-usb-phy" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, k230_usb_phy_of_match);
+
+static struct platform_driver k230_usb_phy_driver = {
+	.probe = k230_usb_phy_probe,
+	.driver = {
+		.name = "k230-usb-phy",
+		.of_match_table = k230_usb_phy_of_match,
+	},
+};
+module_platform_driver(k230_usb_phy_driver);
+
+MODULE_DESCRIPTION("Canaan Kendryte K230 USB 2.0 PHY driver");
+MODULE_AUTHOR("Jiayu Du <jiayu.riscv@isrc.iscas.ac.cn>");
+MODULE_LICENSE("GPL");