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, 79 insertions, 0 deletions

diff --git a/include/video/kyro.h b/include/video/kyro.h
new file mode 100644
index 000000000..418eef6c5
--- /dev/null
+++ b/include/video/kyro.h
@@ -0,0 +1,79 @@
+/*
+ *  linux/drivers/video/kyro/kryo.h
+ *
+ *  Copyright (C) 2002 STMicroelectronics
+ *  Copyright (C) 2004 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _KYRO_H
+#define _KYRO_H
+
+struct kyrofb_info {
+	void __iomem *regbase;
+
+	u32 palette[16];
+	u32 HTot;	/* Hor Total Time    */
+	u32 HFP;	/* Hor Front Porch   */
+	u32 HST;	/* Hor Sync Time     */
+	u32 HBP;	/* Hor Back Porch    */
+	s32 HSP;		/* Hor Sync Polarity */
+	u32 VTot;	/* Ver Total Time    */
+	u32 VFP;	/* Ver Front Porch   */
+	u32 VST;	/* Ver Sync Time     */
+	u32 VBP;	/* Ver Back Porch    */
+	s32 VSP;		/* Ver Sync Polarity */
+	u32 XRES;	/* X Resolution      */
+	u32 YRES;	/* Y Resolution      */
+	u32 VFREQ;	/* Ver Frequency     */
+	u32 PIXCLK;	/* Pixel Clock       */
+	u32 HCLK;	/* Hor Clock         */
+
+	/* Useful to hold depth here for Linux */
+	u8 PIXDEPTH;
+
+	int wc_cookie;
+};
+
+/*
+ * benedict.gaster@superh.com
+ * Added the follow IOCTLS for the creation of overlay services...
+ */
+#define KYRO_IOC_MAGIC 'k'
+
+#define KYRO_IOCTL_OVERLAY_CREATE       _IO(KYRO_IOC_MAGIC, 0)
+#define KYRO_IOCTL_OVERLAY_VIEWPORT_SET _IO(KYRO_IOC_MAGIC, 1)
+#define KYRO_IOCTL_SET_VIDEO_MODE       _IO(KYRO_IOC_MAGIC, 2)
+#define KYRO_IOCTL_UVSTRIDE             _IO(KYRO_IOC_MAGIC, 3)
+#define KYRO_IOCTL_OVERLAY_OFFSET       _IO(KYRO_IOC_MAGIC, 4)
+#define KYRO_IOCTL_STRIDE               _IO(KYRO_IOC_MAGIC, 5)
+
+/*
+ * The follow 3 structures are used to pass data from user space into the kernel
+ * for the creation of overlay surfaces and setting the video mode.
+ */
+typedef struct _OVERLAY_CREATE {
+	u32 ulWidth;
+	u32 ulHeight;
+	int bLinear;
+} overlay_create;
+
+typedef struct _OVERLAY_VIEWPORT_SET {
+	u32 xOrgin;
+	u32 yOrgin;
+	u32 xSize;
+	u32 ySize;
+} overlay_viewport_set;
+
+typedef struct _SET_VIDEO_MODE {
+	u32 ulWidth;
+	u32 ulHeight;
+	u32 ulScan;
+	u8 displayDepth;
+	int bLinear;
+} set_video_mode;
+
+#endif /* _KYRO_H */