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, 200 insertions, 0 deletions

diff --git a/drivers/Makefile b/drivers/Makefile
new file mode 100644
index 000000000..0841ea851
--- /dev/null
+++ b/drivers/Makefile
@@ -0,0 +1,200 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Makefile for the Linux kernel device drivers.
+#
+# 15 Sep 2000, Christoph Hellwig <hch@infradead.org>
+# Rewritten to use lists instead of if-statements.
+#
+
+obj-y				+= cache/
+obj-y				+= irqchip/
+obj-y				+= bus/
+
+obj-y				+= phy/
+
+# GPIO must come after pinctrl as gpios may need to mux pins etc
+obj-$(CONFIG_PINCTRL)		+= pinctrl/
+obj-$(CONFIG_GPIOLIB)		+= gpio/
+obj-y				+= pwm/
+
+# LEDs must come before PCI, it is needed by NPEM driver
+obj-y				+= leds/
+
+obj-y				+= pci/
+
+obj-$(CONFIG_PARISC)		+= parisc/
+obj-$(CONFIG_RAPIDIO)		+= rapidio/
+obj-y				+= video/
+obj-y				+= idle/
+
+# IPMI must come before ACPI in order to provide IPMI opregion support
+obj-y				+= char/ipmi/
+
+obj-$(CONFIG_ACPI)		+= acpi/
+
+# PnP must come after ACPI since it will eventually need to check if acpi
+# was used and do nothing if so
+obj-$(CONFIG_PNP)		+= pnp/
+obj-y				+= amba/
+
+obj-y				+= clk/
+# Many drivers will want to use DMA so this has to be made available
+# really early.
+obj-$(CONFIG_DMADEVICES)	+= dma/
+
+# SOC specific infrastructure drivers.
+obj-y				+= soc/
+obj-$(CONFIG_PM_GENERIC_DOMAINS)	+= pmdomain/
+
+obj-y				+= virtio/
+obj-$(CONFIG_VDPA)		+= vdpa/
+obj-$(CONFIG_XEN)		+= xen/
+
+# regulators early, since some subsystems rely on them to initialize
+obj-$(CONFIG_REGULATOR)		+= regulator/
+
+# reset controllers early, since gpu drivers might rely on them to initialize
+obj-$(CONFIG_RESET_CONTROLLER)	+= reset/
+
+# tty/ comes before char/ so that the VT console is the boot-time
+# default.
+obj-y				+= tty/
+obj-y				+= char/
+
+# iommu/ comes before gpu as gpu are using iommu controllers
+obj-y				+= iommu/
+
+# gpu/ comes after char for AGP vs DRM startup and after iommu
+obj-y				+= gpu/
+
+obj-$(CONFIG_CONNECTOR)		+= connector/
+
+# i810fb depends on char/agp/
+obj-$(CONFIG_FB_I810)           += video/fbdev/i810/
+
+obj-$(CONFIG_PARPORT)		+= parport/
+obj-y				+= base/ block/ misc/ mfd/ nfc/
+obj-$(CONFIG_LIBNVDIMM)		+= nvdimm/
+obj-y				+= dax/
+obj-$(CONFIG_DMA_SHARED_BUFFER) += dma-buf/
+obj-$(CONFIG_NUBUS)		+= nubus/
+obj-y				+= cxl/
+obj-y				+= macintosh/
+obj-y				+= scsi/
+obj-y				+= nvme/
+obj-$(CONFIG_ATA)		+= ata/
+obj-$(CONFIG_TARGET_CORE)	+= target/
+obj-$(CONFIG_MTD)		+= mtd/
+obj-$(CONFIG_SPI)		+= spi/
+obj-$(CONFIG_SPMI)		+= spmi/
+obj-$(CONFIG_HSI)		+= hsi/
+obj-$(CONFIG_SLIMBUS)		+= slimbus/
+obj-y				+= net/
+obj-$(CONFIG_ATM)		+= atm/
+obj-$(CONFIG_FUSION)		+= message/
+obj-y				+= firewire/
+obj-$(CONFIG_UIO)		+= uio/
+obj-$(CONFIG_VFIO)		+= vfio/
+obj-y				+= cdrom/
+obj-y				+= auxdisplay/
+obj-$(CONFIG_PCCARD)		+= pcmcia/
+obj-$(CONFIG_DIO)		+= dio/
+obj-$(CONFIG_SBUS)		+= sbus/
+obj-$(CONFIG_ZORRO)		+= zorro/
+obj-$(CONFIG_ATA_OVER_ETH)	+= block/aoe/
+obj-$(CONFIG_TC)		+= tc/
+obj-$(CONFIG_USB_PHY)		+= usb/
+obj-$(CONFIG_USB)		+= usb/
+obj-$(CONFIG_USB_SUPPORT)	+= usb/
+obj-$(CONFIG_PCI)		+= usb/
+obj-$(CONFIG_USB_GADGET)	+= usb/
+obj-$(CONFIG_OF)		+= usb/
+obj-$(CONFIG_SERIO)		+= input/serio/
+obj-$(CONFIG_GAMEPORT)		+= input/gameport/
+obj-$(CONFIG_INPUT)		+= input/
+obj-$(CONFIG_RTC_LIB)		+= rtc/
+obj-y				+= i2c/ i3c/ media/
+obj-$(CONFIG_PPS)		+= pps/
+obj-y				+= ptp/
+obj-$(CONFIG_W1)		+= w1/
+obj-y				+= power/
+obj-$(CONFIG_HWMON)		+= hwmon/
+obj-$(CONFIG_THERMAL)		+= thermal/
+obj-$(CONFIG_WATCHDOG)		+= watchdog/
+obj-$(CONFIG_MD)		+= md/
+obj-$(CONFIG_BT)		+= bluetooth/
+obj-$(CONFIG_ACCESSIBILITY)	+= accessibility/
+obj-$(CONFIG_EDAC)		+= edac/
+obj-$(CONFIG_EISA)		+= eisa/
+obj-$(CONFIG_PM_OPP)		+= opp/
+obj-$(CONFIG_CPU_FREQ)		+= cpufreq/
+obj-$(CONFIG_CPU_IDLE)		+= cpuidle/
+obj-y				+= mmc/
+obj-y				+= ufs/
+obj-$(CONFIG_MEMSTICK)		+= memstick/
+obj-$(CONFIG_INFINIBAND)	+= infiniband/
+obj-y				+= firmware/
+obj-$(CONFIG_FWCTL)		+= fwctl/
+obj-$(CONFIG_CRYPTO)		+= crypto/
+obj-$(CONFIG_SUPERH)		+= sh/
+obj-y				+= clocksource/
+obj-$(CONFIG_DCA)		+= dca/
+obj-$(CONFIG_HID_SUPPORT)	+= hid/
+obj-$(CONFIG_PPC_PS3)		+= ps3/
+obj-$(CONFIG_OF)		+= of/
+obj-$(CONFIG_SSB)		+= ssb/
+obj-$(CONFIG_BCMA)		+= bcma/
+obj-$(CONFIG_VHOST_RING)	+= vhost/
+obj-$(CONFIG_VHOST_IOTLB)	+= vhost/
+obj-$(CONFIG_VHOST)		+= vhost/
+obj-$(CONFIG_GREYBUS)		+= greybus/
+obj-$(CONFIG_COMEDI)		+= comedi/
+obj-$(CONFIG_GPIB)		+= gpib/
+obj-$(CONFIG_STAGING)		+= staging/
+obj-y				+= platform/
+
+obj-$(CONFIG_MAILBOX)		+= mailbox/
+obj-$(CONFIG_HWSPINLOCK)	+= hwspinlock/
+obj-$(CONFIG_REMOTEPROC)	+= remoteproc/
+obj-$(CONFIG_RPMSG)		+= rpmsg/
+obj-$(CONFIG_SOUNDWIRE)		+= soundwire/
+
+# Virtualization drivers
+obj-y				+= virt/
+obj-$(CONFIG_HYPERV)		+= hv/
+
+obj-$(CONFIG_PM_DEVFREQ)	+= devfreq/
+obj-$(CONFIG_EXTCON)		+= extcon/
+obj-$(CONFIG_MEMORY)		+= memory/
+obj-$(CONFIG_IIO)		+= iio/
+obj-$(CONFIG_IPACK_BUS)		+= ipack/
+obj-$(CONFIG_NTB)		+= ntb/
+obj-$(CONFIG_POWERCAP)		+= powercap/
+obj-$(CONFIG_MCB)		+= mcb/
+obj-$(CONFIG_PERF_EVENTS)	+= perf/
+obj-$(CONFIG_RAS)		+= ras/
+obj-$(CONFIG_USB4)		+= thunderbolt/
+obj-$(CONFIG_CORESIGHT)		+= hwtracing/coresight/
+obj-y				+= hwtracing/intel_th/
+obj-$(CONFIG_STM)		+= hwtracing/stm/
+obj-$(CONFIG_HISI_PTT)		+= hwtracing/ptt/
+obj-y				+= android/
+obj-$(CONFIG_NVMEM)		+= nvmem/
+obj-$(CONFIG_FPGA)		+= fpga/
+obj-$(CONFIG_FSI)		+= fsi/
+obj-$(CONFIG_TEE)		+= tee/
+obj-$(CONFIG_MULTIPLEXER)	+= mux/
+obj-$(CONFIG_SIOX)		+= siox/
+obj-$(CONFIG_GNSS)		+= gnss/
+obj-$(CONFIG_INTERCONNECT)	+= interconnect/
+obj-$(CONFIG_COUNTER)		+= counter/
+obj-$(CONFIG_MOST)		+= most/
+obj-$(CONFIG_PECI)		+= peci/
+obj-$(CONFIG_HTE)		+= hte/
+obj-$(CONFIG_DRM_ACCEL)		+= accel/
+obj-$(CONFIG_CDX_BUS)		+= cdx/
+obj-$(CONFIG_DPLL)		+= dpll/
+obj-y				+= resctrl/
+
+obj-$(CONFIG_DIBS)		+= dibs/
+obj-$(CONFIG_S390)		+= s390/