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, 223 insertions, 0 deletions

diff --git a/drivers/gpu/ipu-v3/ipu-vdi.c b/drivers/gpu/ipu-v3/ipu-vdi.c
new file mode 100644
index 000000000..af9631fd4
--- /dev/null
+++ b/drivers/gpu/ipu-v3/ipu-vdi.c
@@ -0,0 +1,223 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2012-2016 Mentor Graphics Inc.
+ * Copyright (C) 2005-2009 Freescale Semiconductor, Inc.
+ */
+#include <linux/io.h>
+#include "ipu-prv.h"
+
+struct ipu_vdi {
+	void __iomem *base;
+	u32 module;
+	spinlock_t lock;
+	int use_count;
+	struct ipu_soc *ipu;
+};
+
+
+/* VDI Register Offsets */
+#define VDI_FSIZE 0x0000
+#define VDI_C     0x0004
+
+/* VDI Register Fields */
+#define VDI_C_CH_420             (0 << 1)
+#define VDI_C_CH_422             (1 << 1)
+#define VDI_C_MOT_SEL_MASK       (0x3 << 2)
+#define VDI_C_MOT_SEL_FULL       (2 << 2)
+#define VDI_C_MOT_SEL_LOW        (1 << 2)
+#define VDI_C_MOT_SEL_MED        (0 << 2)
+#define VDI_C_BURST_SIZE1_4      (3 << 4)
+#define VDI_C_BURST_SIZE2_4      (3 << 8)
+#define VDI_C_BURST_SIZE3_4      (3 << 12)
+#define VDI_C_BURST_SIZE_MASK    0xF
+#define VDI_C_BURST_SIZE1_OFFSET 4
+#define VDI_C_BURST_SIZE2_OFFSET 8
+#define VDI_C_BURST_SIZE3_OFFSET 12
+#define VDI_C_VWM1_SET_1         (0 << 16)
+#define VDI_C_VWM1_SET_2         (1 << 16)
+#define VDI_C_VWM1_CLR_2         (1 << 19)
+#define VDI_C_VWM3_SET_1         (0 << 22)
+#define VDI_C_VWM3_SET_2         (1 << 22)
+#define VDI_C_VWM3_CLR_2         (1 << 25)
+#define VDI_C_TOP_FIELD_MAN_1    (1 << 30)
+#define VDI_C_TOP_FIELD_AUTO_1   (1 << 31)
+
+static inline u32 ipu_vdi_read(struct ipu_vdi *vdi, unsigned int offset)
+{
+	return readl(vdi->base + offset);
+}
+
+static inline void ipu_vdi_write(struct ipu_vdi *vdi, u32 value,
+				 unsigned int offset)
+{
+	writel(value, vdi->base + offset);
+}
+
+void ipu_vdi_set_field_order(struct ipu_vdi *vdi, v4l2_std_id std, u32 field)
+{
+	bool top_field_0 = false;
+	unsigned long flags;
+	u32 reg;
+
+	switch (field) {
+	case V4L2_FIELD_INTERLACED_TB:
+	case V4L2_FIELD_SEQ_TB:
+	case V4L2_FIELD_TOP:
+		top_field_0 = true;
+		break;
+	case V4L2_FIELD_INTERLACED_BT:
+	case V4L2_FIELD_SEQ_BT:
+	case V4L2_FIELD_BOTTOM:
+		top_field_0 = false;
+		break;
+	default:
+		top_field_0 = (std & V4L2_STD_525_60) ? true : false;
+		break;
+	}
+
+	spin_lock_irqsave(&vdi->lock, flags);
+
+	reg = ipu_vdi_read(vdi, VDI_C);
+	if (top_field_0)
+		reg &= ~(VDI_C_TOP_FIELD_MAN_1 | VDI_C_TOP_FIELD_AUTO_1);
+	else
+		reg |= VDI_C_TOP_FIELD_MAN_1 | VDI_C_TOP_FIELD_AUTO_1;
+	ipu_vdi_write(vdi, reg, VDI_C);
+
+	spin_unlock_irqrestore(&vdi->lock, flags);
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_set_field_order);
+
+void ipu_vdi_set_motion(struct ipu_vdi *vdi, enum ipu_motion_sel motion_sel)
+{
+	unsigned long flags;
+	u32 reg;
+
+	spin_lock_irqsave(&vdi->lock, flags);
+
+	reg = ipu_vdi_read(vdi, VDI_C);
+
+	reg &= ~VDI_C_MOT_SEL_MASK;
+
+	switch (motion_sel) {
+	case MED_MOTION:
+		reg |= VDI_C_MOT_SEL_MED;
+		break;
+	case HIGH_MOTION:
+		reg |= VDI_C_MOT_SEL_FULL;
+		break;
+	default:
+		reg |= VDI_C_MOT_SEL_LOW;
+		break;
+	}
+
+	ipu_vdi_write(vdi, reg, VDI_C);
+
+	spin_unlock_irqrestore(&vdi->lock, flags);
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_set_motion);
+
+void ipu_vdi_setup(struct ipu_vdi *vdi, u32 code, int xres, int yres)
+{
+	unsigned long flags;
+	u32 pixel_fmt, reg;
+
+	spin_lock_irqsave(&vdi->lock, flags);
+
+	reg = ((yres - 1) << 16) | (xres - 1);
+	ipu_vdi_write(vdi, reg, VDI_FSIZE);
+
+	/*
+	 * Full motion, only vertical filter is used.
+	 * Burst size is 4 accesses
+	 */
+	if (code == MEDIA_BUS_FMT_UYVY8_2X8 ||
+	    code == MEDIA_BUS_FMT_UYVY8_1X16 ||
+	    code == MEDIA_BUS_FMT_YUYV8_2X8 ||
+	    code == MEDIA_BUS_FMT_YUYV8_1X16)
+		pixel_fmt = VDI_C_CH_422;
+	else
+		pixel_fmt = VDI_C_CH_420;
+
+	reg = ipu_vdi_read(vdi, VDI_C);
+	reg |= pixel_fmt;
+	reg |= VDI_C_BURST_SIZE2_4;
+	reg |= VDI_C_BURST_SIZE1_4 | VDI_C_VWM1_CLR_2;
+	reg |= VDI_C_BURST_SIZE3_4 | VDI_C_VWM3_CLR_2;
+	ipu_vdi_write(vdi, reg, VDI_C);
+
+	spin_unlock_irqrestore(&vdi->lock, flags);
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_setup);
+
+int ipu_vdi_enable(struct ipu_vdi *vdi)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&vdi->lock, flags);
+
+	if (!vdi->use_count)
+		ipu_module_enable(vdi->ipu, vdi->module);
+
+	vdi->use_count++;
+
+	spin_unlock_irqrestore(&vdi->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_enable);
+
+int ipu_vdi_disable(struct ipu_vdi *vdi)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&vdi->lock, flags);
+
+	if (vdi->use_count) {
+		if (!--vdi->use_count)
+			ipu_module_disable(vdi->ipu, vdi->module);
+	}
+
+	spin_unlock_irqrestore(&vdi->lock, flags);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_disable);
+
+struct ipu_vdi *ipu_vdi_get(struct ipu_soc *ipu)
+{
+	return ipu->vdi_priv;
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_get);
+
+void ipu_vdi_put(struct ipu_vdi *vdi)
+{
+}
+EXPORT_SYMBOL_GPL(ipu_vdi_put);
+
+int ipu_vdi_init(struct ipu_soc *ipu, struct device *dev,
+		 unsigned long base, u32 module)
+{
+	struct ipu_vdi *vdi;
+
+	vdi = devm_kzalloc(dev, sizeof(*vdi), GFP_KERNEL);
+	if (!vdi)
+		return -ENOMEM;
+
+	ipu->vdi_priv = vdi;
+
+	spin_lock_init(&vdi->lock);
+	vdi->module = module;
+	vdi->base = devm_ioremap(dev, base, PAGE_SIZE);
+	if (!vdi->base)
+		return -ENOMEM;
+
+	dev_dbg(dev, "VDI base: 0x%08lx remapped to %p\n", base, vdi->base);
+	vdi->ipu = ipu;
+
+	return 0;
+}
+
+void ipu_vdi_exit(struct ipu_soc *ipu)
+{
+}