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, 204 insertions, 0 deletions

diff --git a/arch/arm/Kconfig.platforms b/arch/arm/Kconfig.platforms
new file mode 100644
index 000000000..2e118b65f
--- /dev/null
+++ b/arch/arm/Kconfig.platforms
@@ -0,0 +1,204 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+menu "Platform selection"
+	depends on MMU
+
+comment "CPU Core family selection"
+
+config ARCH_MULTI_V4
+	bool "ARMv4 based platforms (FA526, StrongARM)"
+	depends on !ARCH_MULTI_V6_V7
+	select ARCH_MULTI_V4_V5
+	select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
+
+config ARCH_MULTI_V4T
+	bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
+	depends on !ARCH_MULTI_V6_V7
+	select ARCH_MULTI_V4_V5
+	select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
+		CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
+		CPU_ARM925T || CPU_ARM940T)
+
+config ARCH_MULTI_V5
+	bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
+	depends on !ARCH_MULTI_V6_V7
+	select ARCH_MULTI_V4_V5
+	select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
+		CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
+		CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
+
+config ARCH_MULTI_V4_V5
+	bool
+
+config ARCH_MULTI_V6
+	bool "ARMv6 based platforms (ARM11)"
+	select ARCH_MULTI_V6_V7
+	select CPU_ARM1176
+
+config ARCH_MULTI_V7
+	bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
+	default y
+	select ARCH_MULTI_V6_V7
+	select CPU_V7
+	select HAVE_SMP
+
+config ARCH_MULTI_V6_V7
+	bool
+	select MIGHT_HAVE_CACHE_L2X0
+
+config ARCH_MULTI_CPU_AUTO
+	def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
+	select ARCH_MULTI_V5
+
+endmenu
+
+config ARCH_VIRT
+	bool "Dummy Virtual Machine"
+	depends on ARCH_MULTI_V7
+	select ARM_AMBA
+	select ARM_GIC
+	select ARM_GIC_V2M if PCI
+	select ARM_GIC_V3
+	select ARM_GIC_V3_ITS if PCI
+	select ARM_PSCI
+	select HAVE_ARM_ARCH_TIMER
+
+config ARCH_AIROHA
+	bool "Airoha SoC Support"
+	depends on ARCH_MULTI_V7
+	select ARM_AMBA
+	select ARM_GIC
+	select ARM_GIC_V3
+	select ARM_PSCI
+	select HAVE_ARM_ARCH_TIMER
+	help
+	  Support for Airoha EN7523 SoCs
+
+config MACH_ASM9260
+	bool "Alphascale ASM9260"
+	depends on ARCH_MULTI_V5
+	depends on CPU_LITTLE_ENDIAN
+	select CPU_ARM926T
+	select ASM9260_TIMER
+	help
+	  Support for Alphascale ASM9260 based platform.
+
+menuconfig ARCH_HPE
+	bool "HPE SoC support"
+	depends on ARCH_MULTI_V7
+	help
+	  This enables support for HPE ARM based BMC chips.
+
+if ARCH_HPE
+
+config ARCH_HPE_GXP
+	bool "HPE GXP SoC"
+	depends on ARCH_MULTI_V7
+	select ARM_VIC
+	select GENERIC_IRQ_CHIP
+	select CLKSRC_MMIO
+	help
+	  HPE GXP is the name of the HPE Soc. This SoC is used to implement many
+	  BMC features at HPE. It supports ARMv7 architecture based on the Cortex
+	  A9 core. It is capable of using an AXI bus to which a memory controller
+	  is attached. It has multiple SPI interfaces to connect boot flash and
+	  BIOS flash. It uses a 10/100/1000 MAC for network connectivity. It
+	  has multiple i2c engines to drive connectivity with a host
+	  infrastructure.
+
+endif
+
+menuconfig ARCH_MOXART
+	bool "MOXA ART SoC"
+	depends on ARCH_MULTI_V4
+	depends on CPU_LITTLE_ENDIAN
+	select CPU_FA526
+	select ARM_DMA_MEM_BUFFERABLE
+	select FARADAY_FTINTC010
+	select FTTMR010_TIMER
+	select GPIOLIB
+	select PHYLIB if NETDEVICES
+	help
+	  Say Y here if you want to run your kernel on hardware with a
+	  MOXA ART SoC.
+	  The MOXA ART SoC is based on a Faraday FA526 ARMv4 32-bit
+	  192 MHz CPU with MMU and 16KB/8KB D/I-cache (UC-7112-LX).
+	  Used on models UC-7101, UC-7112/UC-7110, IA240/IA241, IA3341.
+
+if ARCH_MOXART
+
+config MACH_UC7112LX
+	bool "MOXA UC-7112-LX"
+	depends on ARCH_MOXART
+	help
+	  Say Y here if you intend to run this kernel on a MOXA
+	  UC-7112-LX embedded computer.
+
+endif
+
+config ARCH_NSPIRE
+	bool "TI-NSPIRE based"
+	depends on ARCH_MULTI_V4T
+	depends on CPU_LITTLE_ENDIAN
+	select CPU_ARM926T
+	select GENERIC_IRQ_CHIP
+	select ARM_AMBA
+	select ARM_VIC
+	select ARM_TIMER_SP804
+	select NSPIRE_TIMER
+	select POWER_RESET
+	select POWER_RESET_SYSCON
+	help
+	  This enables support for systems using the TI-NSPIRE CPU
+
+config ARCH_RDA
+	bool "RDA Micro SoCs"
+	depends on ARCH_MULTI_V7
+	select RDA_INTC
+	select RDA_TIMER
+	help
+	  This enables support for the RDA Micro 8810PL SoC family.
+
+menuconfig ARCH_SUNPLUS
+	bool "Sunplus SoCs"
+	depends on ARCH_MULTI_V7
+	help
+	  Support for Sunplus SoC family: SP7021 and succeeding SoC-based systems,
+	  such as the Banana Pi BPI-F2S development board (and derivatives).
+	  (<http://www.sinovoip.com.cn/ecp_view.asp?id=586>)
+	  (<https://tibbo.com/store/plus1.html>)
+
+if ARCH_SUNPLUS
+
+config SOC_SP7021
+	bool "Sunplus SP7021 SoC support"
+	default ARCH_SUNPLUS
+	select HAVE_ARM_ARCH_TIMER
+	select ARM_GIC
+	select ARM_PSCI
+	select PINCTRL
+	select PINCTRL_SPPCTL
+	select SERIAL_SUNPLUS if TTY
+	select SERIAL_SUNPLUS_CONSOLE if TTY
+	help
+	  Support for Sunplus SP7021 SoC. It is based on ARM 4-core
+	  Cortex-A7 with various peripherals (e.g.: I2C, SPI, SDIO,
+	  Ethernet, etc.), FPGA interface,  chip-to-chip bus.
+	  It is designed for industrial control.
+
+endif
+
+config ARCH_UNIPHIER
+	bool "Socionext UniPhier SoCs"
+	depends on ARCH_MULTI_V7
+	select ARCH_HAS_RESET_CONTROLLER
+	select ARM_AMBA
+	select ARM_GLOBAL_TIMER
+	select ARM_GIC
+	select HAVE_ARM_SCU
+	select HAVE_ARM_TWD if SMP
+	select PINCTRL
+	select RESET_CONTROLLER
+	help
+	  Support for UniPhier SoC family developed by Socionext Inc.
+	  (formerly, System LSI Business Division of Panasonic Corporation)