ftrace: Synchronize the initialization of ftrace_opsgrafted

There's some internal state that ftrace_ops needs to have set, but since
it can be declared outside of the ftrace.c code, it calls
ftrace_ops_init() on the ops in every global function. The issue is that
if two tasks call it on the same ops at the same time it is possible to
have the initialization of one corrupt the initialization of the other
call.

Create a ops_mutex to use to synchronize every initialization of the
ftrace_ops. The mutex is taken within checking the ftrace_ops flag that
states it was initializied but the flag is checked again after the mutex
has been taken. Checking first outside the mutex allows it to shortcut
having to take the mutex. But then the check needs to be done again after
the mute is taken in case of races.

Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home
Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock")
Reported-by: sashiko-bot@kernel.org
Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 253 insertions, 0 deletions

diff --git a/drivers/reset/reset-aspeed.c b/drivers/reset/reset-aspeed.c
new file mode 100644
index 000000000..dd2f860a6
--- /dev/null
+++ b/drivers/reset/reset-aspeed.c
@@ -0,0 +1,253 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2024 ASPEED Technology Inc.
+ */
+
+#include <linux/auxiliary_bus.h>
+#include <linux/cleanup.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/reset-controller.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/reset/aspeed,ast2700-scu.h>
+
+#define SCU0_RESET_CTRL1 0x200
+#define SCU0_RESET_CTRL2 0x220
+#define SCU1_RESET_CTRL1 0x200
+#define SCU1_RESET_CTRL2 0x220
+#define SCU1_PCIE3_CTRL 0x908
+
+struct ast2700_reset_signal {
+	bool dedicated_clr; /* dedicated reset clr offset */
+	u32 offset, bit;
+};
+
+struct aspeed_reset_info {
+	unsigned int nr_resets;
+	const struct ast2700_reset_signal *signal;
+};
+
+struct aspeed_reset {
+	struct reset_controller_dev rcdev;
+	struct aspeed_reset_info *info;
+	spinlock_t lock; /* Protect read-modify-write cycle */
+	void __iomem *base;
+};
+
+static const struct ast2700_reset_signal ast2700_reset0_signals[] = {
+	[SCU0_RESET_SDRAM] = { true, SCU0_RESET_CTRL1, BIT(0) },
+	[SCU0_RESET_DDRPHY] = { true, SCU0_RESET_CTRL1, BIT(1) },
+	[SCU0_RESET_RSA] = { true, SCU0_RESET_CTRL1, BIT(2) },
+	[SCU0_RESET_SHA3] = { true, SCU0_RESET_CTRL1, BIT(3) },
+	[SCU0_RESET_HACE] = { true, SCU0_RESET_CTRL1, BIT(4) },
+	[SCU0_RESET_SOC] = { true, SCU0_RESET_CTRL1, BIT(5) },
+	[SCU0_RESET_VIDEO] = { true, SCU0_RESET_CTRL1, BIT(6) },
+	[SCU0_RESET_2D] = { true, SCU0_RESET_CTRL1, BIT(7) },
+	[SCU0_RESET_PCIS] = { true, SCU0_RESET_CTRL1, BIT(8) },
+	[SCU0_RESET_RVAS0] = { true, SCU0_RESET_CTRL1, BIT(9) },
+	[SCU0_RESET_RVAS1] = { true, SCU0_RESET_CTRL1, BIT(10) },
+	[SCU0_RESET_SM3] = { true, SCU0_RESET_CTRL1, BIT(11) },
+	[SCU0_RESET_SM4] = { true, SCU0_RESET_CTRL1, BIT(12) },
+	[SCU0_RESET_CRT0] = { true, SCU0_RESET_CTRL1, BIT(13) },
+	[SCU0_RESET_ECC] = { true, SCU0_RESET_CTRL1, BIT(14) },
+	[SCU0_RESET_DP_PCI] = { true, SCU0_RESET_CTRL1, BIT(15) },
+	[SCU0_RESET_UFS] = { true, SCU0_RESET_CTRL1, BIT(16) },
+	[SCU0_RESET_EMMC] = { true, SCU0_RESET_CTRL1, BIT(17) },
+	[SCU0_RESET_PCIE1RST] = { true, SCU0_RESET_CTRL1, BIT(18) },
+	[SCU0_RESET_PCIE1RSTOE] = { true, SCU0_RESET_CTRL1, BIT(19) },
+	[SCU0_RESET_PCIE0RST] = { true, SCU0_RESET_CTRL1, BIT(20) },
+	[SCU0_RESET_PCIE0RSTOE] = { true, SCU0_RESET_CTRL1, BIT(21) },
+	[SCU0_RESET_JTAG] = { true, SCU0_RESET_CTRL1, BIT(22) },
+	[SCU0_RESET_MCTP0] = { true, SCU0_RESET_CTRL1, BIT(23) },
+	[SCU0_RESET_MCTP1] = { true, SCU0_RESET_CTRL1, BIT(24) },
+	[SCU0_RESET_XDMA0] = { true, SCU0_RESET_CTRL1, BIT(25) },
+	[SCU0_RESET_XDMA1] = { true, SCU0_RESET_CTRL1, BIT(26) },
+	[SCU0_RESET_H2X1] = { true, SCU0_RESET_CTRL1, BIT(27) },
+	[SCU0_RESET_DP] = { true, SCU0_RESET_CTRL1, BIT(28) },
+	[SCU0_RESET_DP_MCU] = { true, SCU0_RESET_CTRL1, BIT(29) },
+	[SCU0_RESET_SSP] = { true, SCU0_RESET_CTRL1, BIT(30) },
+	[SCU0_RESET_H2X0] = { true, SCU0_RESET_CTRL1, BIT(31) },
+	[SCU0_RESET_PORTA_VHUB] = { true, SCU0_RESET_CTRL2, BIT(0) },
+	[SCU0_RESET_PORTA_PHY3] = { true, SCU0_RESET_CTRL2, BIT(1) },
+	[SCU0_RESET_PORTA_XHCI] = { true, SCU0_RESET_CTRL2, BIT(2) },
+	[SCU0_RESET_PORTB_VHUB] = { true, SCU0_RESET_CTRL2, BIT(3) },
+	[SCU0_RESET_PORTB_PHY3] = { true, SCU0_RESET_CTRL2, BIT(4) },
+	[SCU0_RESET_PORTB_XHCI] = { true, SCU0_RESET_CTRL2, BIT(5) },
+	[SCU0_RESET_PORTA_VHUB_EHCI] = { true, SCU0_RESET_CTRL2, BIT(6) },
+	[SCU0_RESET_PORTB_VHUB_EHCI] = { true, SCU0_RESET_CTRL2, BIT(7) },
+	[SCU0_RESET_UHCI] = { true, SCU0_RESET_CTRL2, BIT(8) },
+	[SCU0_RESET_TSP] = { true, SCU0_RESET_CTRL2, BIT(9) },
+	[SCU0_RESET_E2M0] = { true, SCU0_RESET_CTRL2, BIT(10) },
+	[SCU0_RESET_E2M1] = { true, SCU0_RESET_CTRL2, BIT(11) },
+	[SCU0_RESET_VLINK] = { true, SCU0_RESET_CTRL2, BIT(12) },
+};
+
+static const struct ast2700_reset_signal ast2700_reset1_signals[] = {
+	[SCU1_RESET_LPC0] = { true, SCU1_RESET_CTRL1, BIT(0) },
+	[SCU1_RESET_LPC1] = { true, SCU1_RESET_CTRL1, BIT(1) },
+	[SCU1_RESET_MII] = { true, SCU1_RESET_CTRL1, BIT(2) },
+	[SCU1_RESET_PECI] = { true, SCU1_RESET_CTRL1, BIT(3) },
+	[SCU1_RESET_PWM] = { true, SCU1_RESET_CTRL1, BIT(4) },
+	[SCU1_RESET_MAC0] = { true, SCU1_RESET_CTRL1, BIT(5) },
+	[SCU1_RESET_MAC1] = { true, SCU1_RESET_CTRL1, BIT(6) },
+	[SCU1_RESET_MAC2] = { true, SCU1_RESET_CTRL1, BIT(7) },
+	[SCU1_RESET_ADC] = { true, SCU1_RESET_CTRL1, BIT(8) },
+	[SCU1_RESET_SD] = { true, SCU1_RESET_CTRL1, BIT(9) },
+	[SCU1_RESET_ESPI0] = { true, SCU1_RESET_CTRL1, BIT(10) },
+	[SCU1_RESET_ESPI1] = { true, SCU1_RESET_CTRL1, BIT(11) },
+	[SCU1_RESET_JTAG1] = { true, SCU1_RESET_CTRL1, BIT(12) },
+	[SCU1_RESET_SPI0] = { true, SCU1_RESET_CTRL1, BIT(13) },
+	[SCU1_RESET_SPI1] = { true, SCU1_RESET_CTRL1, BIT(14) },
+	[SCU1_RESET_SPI2] = { true, SCU1_RESET_CTRL1, BIT(15) },
+	[SCU1_RESET_I3C0] = { true, SCU1_RESET_CTRL1, BIT(16) },
+	[SCU1_RESET_I3C1] = { true, SCU1_RESET_CTRL1, BIT(17) },
+	[SCU1_RESET_I3C2] = { true, SCU1_RESET_CTRL1, BIT(18) },
+	[SCU1_RESET_I3C3] = { true, SCU1_RESET_CTRL1, BIT(19) },
+	[SCU1_RESET_I3C4] = { true, SCU1_RESET_CTRL1, BIT(20) },
+	[SCU1_RESET_I3C5] = { true, SCU1_RESET_CTRL1, BIT(21) },
+	[SCU1_RESET_I3C6] = { true, SCU1_RESET_CTRL1, BIT(22) },
+	[SCU1_RESET_I3C7] = { true, SCU1_RESET_CTRL1, BIT(23) },
+	[SCU1_RESET_I3C8] = { true, SCU1_RESET_CTRL1, BIT(24) },
+	[SCU1_RESET_I3C9] = { true, SCU1_RESET_CTRL1, BIT(25) },
+	[SCU1_RESET_I3C10] = { true, SCU1_RESET_CTRL1, BIT(26) },
+	[SCU1_RESET_I3C11] = { true, SCU1_RESET_CTRL1, BIT(27) },
+	[SCU1_RESET_I3C12] = { true, SCU1_RESET_CTRL1, BIT(28) },
+	[SCU1_RESET_I3C13] = { true, SCU1_RESET_CTRL1, BIT(29) },
+	[SCU1_RESET_I3C14] = { true, SCU1_RESET_CTRL1, BIT(30) },
+	[SCU1_RESET_I3C15] = { true, SCU1_RESET_CTRL1, BIT(31) },
+	[SCU1_RESET_MCU0] = { true, SCU1_RESET_CTRL2, BIT(0) },
+	[SCU1_RESET_MCU1] = { true, SCU1_RESET_CTRL2, BIT(1) },
+	[SCU1_RESET_H2A_SPI1] = { true, SCU1_RESET_CTRL2, BIT(2) },
+	[SCU1_RESET_H2A_SPI2] = { true, SCU1_RESET_CTRL2, BIT(3) },
+	[SCU1_RESET_UART0] = { true, SCU1_RESET_CTRL2, BIT(4) },
+	[SCU1_RESET_UART1] = { true, SCU1_RESET_CTRL2, BIT(5) },
+	[SCU1_RESET_UART2] = { true, SCU1_RESET_CTRL2, BIT(6) },
+	[SCU1_RESET_UART3] = { true, SCU1_RESET_CTRL2, BIT(7) },
+	[SCU1_RESET_I2C_FILTER] = { true, SCU1_RESET_CTRL2, BIT(8) },
+	[SCU1_RESET_CALIPTRA] = { true, SCU1_RESET_CTRL2, BIT(9) },
+	[SCU1_RESET_XDMA] = { true, SCU1_RESET_CTRL2, BIT(10) },
+	[SCU1_RESET_FSI] = { true, SCU1_RESET_CTRL2, BIT(12) },
+	[SCU1_RESET_CAN] = { true, SCU1_RESET_CTRL2, BIT(13) },
+	[SCU1_RESET_MCTP] = { true, SCU1_RESET_CTRL2, BIT(14) },
+	[SCU1_RESET_I2C] = { true, SCU1_RESET_CTRL2, BIT(15) },
+	[SCU1_RESET_UART6] = { true, SCU1_RESET_CTRL2, BIT(16) },
+	[SCU1_RESET_UART7] = { true, SCU1_RESET_CTRL2, BIT(17) },
+	[SCU1_RESET_UART8] = { true, SCU1_RESET_CTRL2, BIT(18) },
+	[SCU1_RESET_UART9] = { true, SCU1_RESET_CTRL2, BIT(19) },
+	[SCU1_RESET_LTPI0] = { true, SCU1_RESET_CTRL2, BIT(20) },
+	[SCU1_RESET_VGAL] = { true, SCU1_RESET_CTRL2, BIT(21) },
+	[SCU1_RESET_LTPI1] = { true, SCU1_RESET_CTRL2, BIT(22) },
+	[SCU1_RESET_ACE] = { true, SCU1_RESET_CTRL2, BIT(23) },
+	[SCU1_RESET_E2M] = { true, SCU1_RESET_CTRL2, BIT(24) },
+	[SCU1_RESET_UHCI] = { true, SCU1_RESET_CTRL2, BIT(25) },
+	[SCU1_RESET_PORTC_USB2UART] = { true, SCU1_RESET_CTRL2, BIT(26) },
+	[SCU1_RESET_PORTC_VHUB_EHCI] = { true, SCU1_RESET_CTRL2, BIT(27) },
+	[SCU1_RESET_PORTD_USB2UART] = { true, SCU1_RESET_CTRL2, BIT(28) },
+	[SCU1_RESET_PORTD_VHUB_EHCI] = { true, SCU1_RESET_CTRL2, BIT(29) },
+	[SCU1_RESET_H2X] = { true, SCU1_RESET_CTRL2, BIT(30) },
+	[SCU1_RESET_I3CDMA] = { true, SCU1_RESET_CTRL2, BIT(31) },
+	[SCU1_RESET_PCIE2RST] = { false, SCU1_PCIE3_CTRL, BIT(0) },
+};
+
+static inline struct aspeed_reset *to_aspeed_reset(struct reset_controller_dev *rcdev)
+{
+	return container_of(rcdev, struct aspeed_reset, rcdev);
+}
+
+static int aspeed_reset_assert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	if (rc->info->signal[id].dedicated_clr) {
+		writel(rc->info->signal[id].bit, reg_offset);
+	} else {
+		guard(spinlock_irqsave)(&rc->lock);
+		writel(readl(reg_offset) & ~rc->info->signal[id].bit, reg_offset);
+	}
+
+	return 0;
+}
+
+static int aspeed_reset_deassert(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	if (rc->info->signal[id].dedicated_clr) {
+		writel(rc->info->signal[id].bit, reg_offset + 0x04);
+	} else {
+		guard(spinlock_irqsave)(&rc->lock);
+		writel(readl(reg_offset) | rc->info->signal[id].bit, reg_offset);
+	}
+
+	return 0;
+}
+
+static int aspeed_reset_status(struct reset_controller_dev *rcdev, unsigned long id)
+{
+	struct aspeed_reset *rc = to_aspeed_reset(rcdev);
+	void __iomem *reg_offset = rc->base + rc->info->signal[id].offset;
+
+	return (readl(reg_offset) & rc->info->signal[id].bit) ? 1 : 0;
+}
+
+static const struct reset_control_ops aspeed_reset_ops = {
+	.assert = aspeed_reset_assert,
+	.deassert = aspeed_reset_deassert,
+	.status = aspeed_reset_status,
+};
+
+static int aspeed_reset_probe(struct auxiliary_device *adev,
+			      const struct auxiliary_device_id *id)
+{
+	struct aspeed_reset *reset;
+	struct device *dev = &adev->dev;
+
+	reset = devm_kzalloc(dev, sizeof(*reset), GFP_KERNEL);
+	if (!reset)
+		return -ENOMEM;
+
+	spin_lock_init(&reset->lock);
+
+	reset->info = (struct aspeed_reset_info *)id->driver_data;
+	reset->rcdev.owner = THIS_MODULE;
+	reset->rcdev.nr_resets = reset->info->nr_resets;
+	reset->rcdev.ops = &aspeed_reset_ops;
+	reset->rcdev.of_node = dev->parent->of_node;
+	reset->rcdev.dev = dev;
+	reset->rcdev.of_reset_n_cells = 1;
+	reset->base = (void __iomem *)adev->dev.platform_data;
+
+	return devm_reset_controller_register(dev, &reset->rcdev);
+}
+
+static const struct aspeed_reset_info ast2700_reset0_info = {
+	.nr_resets = ARRAY_SIZE(ast2700_reset0_signals),
+	.signal = ast2700_reset0_signals,
+};
+
+static const struct aspeed_reset_info ast2700_reset1_info = {
+	.nr_resets = ARRAY_SIZE(ast2700_reset1_signals),
+	.signal = ast2700_reset1_signals,
+};
+
+static const struct auxiliary_device_id aspeed_reset_ids[] = {
+	{ .name = "clk_ast2700.reset0", .driver_data = (kernel_ulong_t)&ast2700_reset0_info },
+	{ .name = "clk_ast2700.reset1", .driver_data = (kernel_ulong_t)&ast2700_reset1_info },
+	{ }
+};
+MODULE_DEVICE_TABLE(auxiliary, aspeed_reset_ids);
+
+static struct auxiliary_driver aspeed_reset_driver = {
+	.probe		= aspeed_reset_probe,
+	.id_table	= aspeed_reset_ids,
+};
+
+module_auxiliary_driver(aspeed_reset_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED SoC Reset Controller Driver");
+MODULE_LICENSE("GPL");