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, 142 insertions, 0 deletions

diff --git a/drivers/char/agp/Kconfig b/drivers/char/agp/Kconfig
new file mode 100644
index 000000000..c47eb7bf0
--- /dev/null
+++ b/drivers/char/agp/Kconfig
@@ -0,0 +1,142 @@
+# SPDX-License-Identifier: GPL-2.0
+menuconfig AGP
+	tristate "/dev/agpgart (AGP Support)"
+	depends on ALPHA || PARISC || PPC || X86
+	depends on PCI
+	help
+	  AGP (Accelerated Graphics Port) is a bus system mainly used to
+	  connect graphics cards to the rest of the system.
+
+	  If you have an AGP system and you say Y here, it will be possible to
+	  use the AGP features of your 3D rendering video card. This code acts
+	  as a sort of "AGP driver" for the motherboard's chipset.
+
+	  If you need more texture memory than you can get with the AGP GART
+	  (theoretically up to 256 MB, but in practice usually 64 or 128 MB
+	  due to kernel allocation issues), you could use PCI accesses
+	  and have up to a couple gigs of texture space.
+
+	  Note that this is the only means to have X/GLX use
+	  write-combining with MTRR support on the AGP bus. Without it, OpenGL
+	  direct rendering will be a lot slower but still faster than PIO.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called agpgart.
+
+	  You should say Y here if you want to use GLX or DRI.
+
+	  If unsure, say N.
+
+config AGP_ALI
+	tristate "ALI chipset support"
+	depends on AGP && X86_32
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on the following ALi chipsets.  The supported chipsets
+	  include M1541, M1621, M1631, M1632, M1641,M1647,and M1651.
+	  For the ALi-chipset question, ALi suggests you refer to
+	  <http://www.ali.com.tw/>.
+
+	  The M1541 chipset can do AGP 1x and 2x, but note that there is an
+	  acknowledged incompatibility with Matrox G200 cards. Due to
+	  timing issues, this chipset cannot do AGP 2x with the G200.
+	  This is a hardware limitation. AGP 1x seems to be fine, though.
+
+config AGP_ATI
+	tristate "ATI chipset support"
+	depends on AGP && X86_32
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on the ATI RadeonIGP family of chipsets.
+
+config AGP_AMD
+	tristate "AMD Irongate, 761, and 762 chipset support"
+	depends on AGP && X86_32
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on AMD Irongate, 761, and 762 chipsets.
+
+config AGP_AMD64
+	tristate "AMD Opteron/Athlon64 on-CPU GART support"
+	depends on AGP && X86 && AMD_NB
+	help
+	  This option gives you AGP support for the GLX component of
+	  X using the on-CPU northbridge of the AMD Athlon64/Opteron CPUs.
+	  You still need an external AGP bridge like the AMD 8151, VIA
+	  K8T400M, SiS755. It may also support other AGP bridges when loaded
+	  with agp_try_unsupported=1.
+
+config AGP_INTEL
+	tristate "Intel 440LX/BX/GX, I8xx and E7x05 chipset support"
+	depends on AGP && X86
+	select INTEL_GTT
+	help
+	  This option gives you AGP support for the GLX component of X
+	  on Intel 440LX/BX/GX, 815, 820, 830, 840, 845, 850, 860, 875,
+	  E7205 and E7505 chipsets and full support for the 810, 815, 830M,
+	  845G, 852GM, 855GM, 865G and I915 integrated graphics chipsets.
+
+
+
+config AGP_NVIDIA
+	tristate "NVIDIA nForce/nForce2 chipset support"
+	depends on AGP && X86_32
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on NVIDIA chipsets including nForce and nForce2
+
+config AGP_SIS
+	tristate "SiS chipset support"
+	depends on AGP && X86
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on Silicon Integrated Systems [SiS] chipsets.
+
+	  Note that 5591/5592 AGP chipsets are NOT supported.
+
+
+config AGP_SWORKS
+	tristate "Serverworks LE/HE chipset support"
+	depends on AGP && X86_32
+	help
+	  Say Y here to support the Serverworks AGP card.  See
+	  <http://www.serverworks.com/> for product descriptions and images.
+
+config AGP_VIA
+	tristate "VIA chipset support"
+	depends on AGP && X86
+	help
+	  This option gives you AGP support for the GLX component of
+	  X on VIA MVP3/Apollo Pro chipsets.
+
+config AGP_PARISC
+	tristate "HP Quicksilver AGP support"
+	depends on AGP && PARISC && 64BIT && IOMMU_SBA
+	help
+	  This option gives you AGP GART support for the HP Quicksilver
+	  AGP bus adapter on HP PA-RISC machines (Ok, just on the C8000
+	  workstation...)
+
+config AGP_ALPHA_CORE
+	tristate "Alpha AGP support"
+	depends on AGP && (ALPHA_GENERIC || ALPHA_TITAN || ALPHA_MARVEL)
+	default AGP
+
+config AGP_UNINORTH
+	tristate "Apple UniNorth & U3 AGP support"
+	depends on AGP && PPC_PMAC
+	help
+	  This option gives you AGP support for Apple machines with a
+	  UniNorth or U3 (Apple G5) bridge.
+
+config AGP_EFFICEON
+	tristate "Transmeta Efficeon support"
+	depends on AGP && X86_32
+	help
+	  This option gives you AGP support for the Transmeta Efficeon
+	  series processors with integrated northbridges.
+
+config INTEL_GTT
+	tristate
+	depends on X86 && PCI
+