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, 285 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/incomplete-devices.yaml b/Documentation/devicetree/bindings/incomplete-devices.yaml
new file mode 100644
index 000000000..4bb6c0141
--- /dev/null
+++ b/Documentation/devicetree/bindings/incomplete-devices.yaml
@@ -0,0 +1,285 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/incomplete-devices.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Rejected, Legacy or Incomplete Devices
+
+maintainers:
+  - Rob Herring <robh@kernel.org>
+
+description:
+  Some devices will not or should not get a proper Devicetree bindings, but
+  their compatibles are present in Linux drivers for various reasons.
+
+  Examples are devices using ACPI PRP0001 with non-updatable firmware/ACPI
+  tables or old PowerPC platforms without in-tree DTS.
+
+  Following list of devices is an incomplete schema with a goal to pass DT schema
+  checks on undocumented compatibles but also reject any DTS file using such
+  un-approved compatible.
+
+  Usage of any of following compatibles is not allowed in Devicetree sources,
+  even if they come from immutable firmware.
+
+properties:
+  compatible:
+    oneOf:
+      - description:
+          Rejected compatibles in Devicetree, but used in ACPI-based devices
+          with non-updatable firmware/ACPI tables (via ACPI PRP0001)
+        enum:
+          - broadcom,bcm5241
+          - ltr,ltrf216a
+
+      - description: Legacy compatibles used on Macintosh devices
+        enum:
+          - AAPL,3500
+          - AAPL,7500
+          - AAPL,8500
+          - AAPL,9500
+          - AAPL,accelerometer_1
+          - AAPL,e411
+          - AAPL,Gossamer
+          - AAPL,PowerBook1998
+          - AAPL,ShinerESB
+          - adm1030
+          - amd-0137
+          - B5221
+          - bmac+
+          - burgundy
+          - cobalt
+          - cy28508
+          - daca
+          - fcu
+          - gatwick
+          - gmac
+          - heathrow
+          - heathrow-ata
+          - heathrow-media-bay
+          - i2sbus
+          - i2s-modem
+          - iMac
+          - K2-GMAC
+          - k2-i2c
+          - K2-Keylargo
+          - K2-UATA
+          - kauai-ata
+          - Keylargo
+          - keylargo-ata
+          - keylargo-media-bay
+          - lm87cimt
+          - MAC,adm1030
+          - MAC,ds1775
+          - MacRISC
+          - MacRISC2
+          - MacRISC3
+          - MacRISC4
+          - max6690
+          - ohare
+          - ohare-media-bay
+          - ohare-swim3
+          - PowerBook1,1
+          - PowerBook2,1
+          - PowerBook2,2
+          - PowerBook3,1
+          - PowerBook3,2
+          - PowerBook3,3
+          - PowerBook3,4
+          - PowerBook3,5
+          - PowerBook4,1
+          - PowerBook4,2
+          - PowerBook4,3
+          - PowerBook5,1
+          - PowerBook5,2
+          - PowerBook5,3
+          - PowerBook5,4
+          - PowerBook5,5
+          - PowerBook5,6
+          - PowerBook5,7
+          - PowerBook5,8
+          - PowerBook5,9
+          - PowerBook6,3
+          - PowerBook6,5
+          - PowerBook6,7
+          - PowerMac10,1
+          - PowerMac10,2
+          - PowerMac1,1
+          - PowerMac11,2
+          - PowerMac12,1
+          - PowerMac2,1
+          - PowerMac2,2
+          - PowerMac3,1
+          - PowerMac3,4
+          - PowerMac3,5
+          - PowerMac3,6
+          - PowerMac4,1
+          - PowerMac4,2
+          - PowerMac4,4
+          - PowerMac4,5
+          - PowerMac7,2
+          - PowerMac7,3
+          - PowerMac8,1
+          - PowerMac8,2
+          - PowerMac9,1
+          - paddington
+          - RackMac1,1
+          - RackMac1,2
+          - RackMac3,1
+          - screamer
+          - shasta-ata
+          - sms
+          - smu-rpm-fans
+          - smu-sat
+          - smu-sensors
+          - snapper
+          - swim3
+          - tumbler
+          - u3-agp
+          - u3-dart
+          - u3-ht
+          - u4-dart
+          - u4-pcie
+          - U4-pcie
+          - uni-n-i2c
+          - uni-north
+
+      - description: Legacy compatibles used on other PowerPC devices
+        enum:
+          - 1682m-gizmo
+          - 1682m-gpio
+          - 1682m-rng
+          - 1682m-sdc
+          - amcc,ppc440epx-rng
+          - amcc,ppc460ex-bcsr
+          - amcc,ppc460ex-crypto
+          - amcc,ppc460ex-rng
+          - amcc,ppc460sx-crypto
+          - amcc,ppc4xx-crypto
+          - amcc,sata-460ex
+          - CBEA,platform-open-pic
+          - CBEA,platform-spider-pic
+          - direct-mapped
+          - display
+          - gpio-mdio
+          - hawk-bridge
+          - hawk-pci
+          - IBM,CBEA
+          - IBM,lhca
+          - IBM,lhea
+          - IBM,lhea-ethernet
+          - ibm,axon-msic
+          - Momentum,Apache
+          - Momentum,Maple
+          - mai-logic,articia-s
+          - mpc10x-pci
+          - mpc5200b-fec-phy
+          - mpc5200-serial
+          - mpc5200-sram
+          - nintendo,flipper
+          - nintendo,flipper-exi
+          - nintendo,flipper-pi
+          - nintendo,flipper-pic
+          - nintendo,hollywood
+          - nintendo,hollywood-pic
+          - nintendo,latte-exi
+          - nintendo,latte-srnprot
+          - ohci-be
+          - ohci-bigendian
+          - ohci-le
+          - PA6T-1682M
+          - pasemi,1682m-iob
+          - pasemi,localbus
+          - pasemi,localbus-nand
+          - pasemi,nemo
+          - pasemi,pwrficient
+          - pasemi,pwrficient-rng
+          - pasemi,rootbus
+          - pasemi,sdc
+          - soc
+          - sony,ps3
+          - sti,platform-spider-pic
+
+      - description: Legacy compatibles used on SPARC devices
+        enum:
+          - bq4802
+          - ds1287
+          - i2cpcf,8584
+          - isa-m5819p
+          - isa-m5823p
+          - m5819
+          - qcn
+          - sab82532
+          - su
+          - sun4v
+          - SUNW,bbc-beep
+          - SUNW,bbc-i2c
+          - SUNW,CS4231
+          - SUNW,ebus-pic16f747-env
+          - SUNW,kt-cwq
+          - SUNW,kt-mau
+          - SUNW,n2-cwq
+          - SUNW,n2-mau
+          - SUNW,niusl
+          - SUNW,smbus-beep
+          - SUNW,sun4v-console
+          - SUNW,sun4v-pci
+          - SUNW,vf-cwq
+          - SUNW,vf-mau
+
+      - description: Incomplete and/or legacy compatibles for unknown devices
+        enum:
+          - electra-cf
+          - i2cpcf,8584
+          - virtio,uml
+
+      - description: Linux kernel unit tests and sample code
+        enum:
+          - audio-graph-card2-custom-sample
+          - compat1
+          - compat2
+          - compat3
+          - gpio-mockup
+          - gpio-simulator
+          - gpio-virtuser
+          - linux,spi-loopback-test
+          - mailbox-test
+          - regulator-virtual-consumer
+          - test-device
+
+      - description:
+          Devices on MIPS platform, without any DTS users.  These are
+          unlikely to get converted to DT schema.
+        enum:
+          - mti,ranchu
+
+      - description:
+          Devices on PowerPC platform, without any DTS users.  These are
+          unlikely to get converted to DT schema.
+        enum:
+          - fujitsu,coral
+          - fujitsu,lime
+          - fujitsu,MB86276
+          - fujitsu,MB86277
+          - fujitsu,MB86293
+          - fujitsu,MB86294
+          - fujitsu,mint
+          - ibm,axon-msic
+          - ibm,pmemory
+          - ibm,pmemory-v2
+          - ibm,power-rng
+          - ibm,ppc4xx-spi
+          - ibm,sdram-4xx-ddr2
+          - ibm,secureboot
+          - ibm,secureboot-v1
+          - ibm,secureboot-v2
+          - ibm,secvar-backend
+          - sgy,gpio-halt
+          - wrs,epld-localbus
+
+required:
+  - compatible
+  - broken-usage-of-incorrect-compatible
+
+additionalProperties: false