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/drivers/video/logo/Kconfig b/drivers/video/logo/Kconfig
new file mode 100644
index 000000000..cda15b958
--- /dev/null
+++ b/drivers/video/logo/Kconfig
@@ -0,0 +1,79 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Logo configuration
+#
+
+menuconfig LOGO
+	bool "Bootup logo"
+	depends on FB_CORE || SGI_NEWPORT_CONSOLE
+	help
+	  Enable and select frame buffer bootup logos.
+	  Monochrome logos will also be used by the DRM panic handler, if
+	  enabled.
+
+if LOGO
+
+config FB_LOGO_EXTRA
+	bool
+	depends on FB=y
+	default y if SPU_BASE
+
+config LOGO_LINUX_MONO
+	bool "Standard black and white Linux logo"
+
+config LOGO_LINUX_MONO_FILE
+	string "Monochrome logo .pbm file"
+	depends on LOGO_LINUX_MONO
+	default "drivers/video/logo/logo_superh_mono.pbm" if SUPERH
+	default "drivers/video/logo/logo_linux_mono.pbm"
+	help
+	  Takes a path to a monochromatic logo in the portable pixmap file
+	  format (.pbm). This defaults to the Tux penguin.
+
+	  For example, the below ImageMagick command can be used to reduce
+	  an image to black and white and convert it into a pbm file:
+
+	    magick source_image -compress none destination.pbm
+
+config LOGO_LINUX_VGA16
+	bool "Standard 16-color Linux logo"
+
+config LOGO_LINUX_VGA16_FILE
+	string "16-color logo .ppm file"
+	depends on LOGO_LINUX_VGA16
+	default "drivers/video/logo/logo_superh_vga16.ppm" if SUPERH
+	default "drivers/video/logo/logo_linux_vga16.ppm"
+	help
+	  Takes a path to a logo in the portable pixmap file format (.ppm),
+	  using the 16 colors from the drivers/video/logo/clut_vga16.ppm
+	  palette. This defaults to the Tux penguin.
+
+	  For example, the below ImageMagick command can be used to reduce an
+	  image to the VGA 16 colors palette and convert into a ppm file:
+
+	    magick source_image -compress none \
+	      -remap drivers/video/logo/clut_vga16.ppm destination.ppm
+
+config LOGO_LINUX_CLUT224
+	bool "Standard 224-color Linux logo"
+	default y
+
+config LOGO_LINUX_CLUT224_FILE
+	string "224-color logo .ppm file"
+	depends on LOGO_LINUX_CLUT224
+	default "drivers/video/logo/logo_dec_clut224.ppm" if MACH_DECSTATION || ALPHA
+	default "drivers/video/logo/logo_parisc_clut224.ppm" if PARISC
+	default "drivers/video/logo/logo_sgi_clut224.ppm" if SGI_IP22 || SGI_IP27 || SGI_IP32
+	default "drivers/video/logo/logo_sun_clut224.ppm" if SPARC
+	default "drivers/video/logo/logo_superh_clut224.ppm" if SUPERH
+	default "drivers/video/logo/logo_linux_clut224.ppm"
+	help
+	  Takes a path to a 224-color logo in the portable pixmap file
+	  format (.ppm). This defaults to the Tux penguin.
+
+	  For example, the below ImageMagick command can be used to reduce
+	  an image palette to 224 colors and convert it into a ppm file:
+
+	    magick source_image -compress none -colors 224 destination.ppm
+
+endif # LOGO