From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops 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 --- scripts/Makefile.dtbs | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 scripts/Makefile.dtbs (limited to 'scripts/Makefile.dtbs') diff --git a/scripts/Makefile.dtbs b/scripts/Makefile.dtbs new file mode 100644 index 000000000..c4e466390 --- /dev/null +++ b/scripts/Makefile.dtbs @@ -0,0 +1,153 @@ +# SPDX-License-Identifier: GPL-2.0-only + +all-dtb := $(dtb-y) $(dtb-) + +# If CONFIG_OF_ALL_DTBS is enabled, all DT blobs are built +dtb-$(CONFIG_OF_ALL_DTBS) += $(dtb-) + +# Composite DTB (i.e. DTB constructed by overlay) +multi-dtb-y := $(call multi-search, $(dtb-y), .dtb, -dtbs) +# Primitive DTB compiled from *.dts +real-dtb-y := $(call real-search, $(dtb-y), .dtb, -dtbs) +# Base DTB that overlay is applied onto +base-dtb-y := $(filter %.dtb, $(call real-search, $(multi-dtb-y), .dtb, -dtbs)) + +# Ensure that any .dtbo is applied to at least one base .dtb. Otherwise, it +# does not get validated. +applied-dtbo := $(filter %.dtbo, \ + $(call real-search, $(call multi-search, $(all-dtb), .dtb, -dtbs), .dtb, -dtbs)) +unapplied-dtbo := $(filter-out $(applied-dtbo),$(filter %.dtbo, $(dtb-y))) +$(if $(unapplied-dtbo), $(warning .dtbo is not applied to any base: $(unapplied-dtbo))) + +dtb-y := $(addprefix $(obj)/, $(dtb-y)) +multi-dtb-y := $(addprefix $(obj)/, $(multi-dtb-y)) +real-dtb-y := $(addprefix $(obj)/, $(real-dtb-y)) + +always-y += $(dtb-y) +targets += $(real-dtb-y) + +# dtbs-list +# --------------------------------------------------------------------------- + +ifdef need-dtbslist +subdir-dtbslist := $(addsuffix /dtbs-list, $(subdir-ym)) +dtb-y += $(subdir-dtbslist) +always-y += $(obj)/dtbs-list +endif + +$(subdir-dtbslist): $(obj)/%/dtbs-list: $(obj)/% ; + +$(obj)/dtbs-list: $(dtb-y) FORCE + $(call if_changed,gen_order) + +# Assembly file to wrap dtb(o) +# --------------------------------------------------------------------------- + +builtin-dtb-section = $(if $(filter arch/$(SRCARCH)/boot/dts%, $(obj)),.dtb.init.rodata,.rodata) + +# Generate an assembly file to wrap the output of the device tree compiler +quiet_cmd_wrap_S_dtb = WRAP $@ + cmd_wrap_S_dtb = { \ + symbase=__$(patsubst .%,%,$(suffix $<))_$(subst -,_,$(notdir $*)); \ + echo '\#include '; \ + echo '.section $(builtin-dtb-section),"a"'; \ + echo '.balign STRUCT_ALIGNMENT'; \ + echo ".global $${symbase}_begin"; \ + echo "$${symbase}_begin:"; \ + echo '.incbin "$<" '; \ + echo ".global $${symbase}_end"; \ + echo "$${symbase}_end:"; \ + echo '.balign STRUCT_ALIGNMENT'; \ + } > $@ + +$(obj)/%.dtb.S: $(obj)/%.dtb FORCE + $(call if_changed,wrap_S_dtb) + +$(obj)/%.dtbo.S: $(obj)/%.dtbo FORCE + $(call if_changed,wrap_S_dtb) + +# Schema check +# --------------------------------------------------------------------------- + +ifneq ($(CHECK_DTBS),) +DT_CHECKER ?= dt-validate +DT_CHECKER_FLAGS ?= $(if $(DT_SCHEMA_FILES),-l $(DT_SCHEMA_FILES),-m) +DT_BINDING_DIR := Documentation/devicetree/bindings +DT_TMP_SCHEMA := $(objtree)/$(DT_BINDING_DIR)/processed-schema.json +dtb-check-enabled = $(if $(filter %.dtb, $@),y) +endif + +quiet_dtb_check_tag = $(if $(dtb-check-enabled),[C], ) +cmd_dtb_check = $(if $(dtb-check-enabled),; $(DT_CHECKER) $(DT_CHECKER_FLAGS) -u $(srctree)/$(DT_BINDING_DIR) -p $(DT_TMP_SCHEMA) $@ || true) + +# Overlay +# --------------------------------------------------------------------------- + +# NOTE: +# Do not replace $(filter %.dtb %.dtbo, $^) with $(real-prereqs). When a single +# DTB is turned into a multi-blob DTB, $^ will contain header file dependencies +# recorded in the .*.cmd file. +quiet_cmd_fdtoverlay = OVL $(quiet_dtb_check_tag) $@ + cmd_fdtoverlay = $(objtree)/scripts/dtc/fdtoverlay -o $@ -i $(filter %.dtb %.dtbo, $^) $(cmd_dtb_check) + +$(multi-dtb-y): $(DT_TMP_SCHEMA) FORCE + $(call if_changed,fdtoverlay) +$(call multi_depend, $(multi-dtb-y), .dtb, -dtbs) + +# DTC +# --------------------------------------------------------------------------- + +DTC ?= $(objtree)/scripts/dtc/dtc +DTC_FLAGS += -Wno-unique_unit_address + +# Disable noisy checks by default +ifeq ($(findstring 1,$(KBUILD_EXTRA_WARN)),) +DTC_FLAGS += -Wno-unit_address_vs_reg \ + -Wno-avoid_unnecessary_addr_size \ + -Wno-alias_paths \ + -Wno-interrupt_map \ + -Wno-simple_bus_reg +else +DTC_FLAGS += -Wunique_unit_address_if_enabled +endif + +ifneq ($(findstring 2,$(KBUILD_EXTRA_WARN)),) +DTC_FLAGS += -Wnode_name_chars_strict \ + -Wproperty_name_chars_strict \ + -Wunique_unit_address +endif + +DTC_FLAGS += $(DTC_FLAGS_$(target-stem)) + +# Set -@ if the target is a base DTB that overlay is applied onto +DTC_FLAGS += $(if $(filter $(patsubst $(obj)/%,%,$@), $(base-dtb-y)), -@) + +DTC_INCLUDE := $(srctree)/scripts/dtc/include-prefixes + +dtc_cpp_flags = -Wp,-MMD,$(depfile).pre.tmp -nostdinc -I $(DTC_INCLUDE) -undef -D__DTS__ + +dtc-tmp = $(subst $(comma),_,$(dot-target).dts.tmp) + +quiet_cmd_dtc = DTC $(quiet_dtb_check_tag) $@ + cmd_dtc = \ + $(HOSTCC) -E $(dtc_cpp_flags) -x assembler-with-cpp -o $(dtc-tmp) $< ; \ + $(DTC) -o $@ -b 0 $(addprefix -i,$(dir $<) $(DTC_INCLUDE)) \ + $(DTC_FLAGS) -d $(depfile).dtc.tmp $(dtc-tmp) ; \ + cat $(depfile).pre.tmp $(depfile).dtc.tmp > $(depfile) \ + $(cmd_dtb_check) + +$(obj)/%.dtb: $(obj)/%.dts $(DTC) $(DT_TMP_SCHEMA) FORCE + $(call if_changed_dep,dtc) + +$(obj)/%.dtbo: $(src)/%.dtso $(DTC) FORCE + $(call if_changed_dep,dtc) + +# targets +# --------------------------------------------------------------------------- + +targets += $(always-y) + +# %.dtb.o <- %.dtb.S <- %.dtb <- %.dts +# %.dtbo.o <- %.dtbo.S <- %.dtbo <- %.dtso +targets += $(call intermediate_targets, .dtb.o, .dtb.S .dtb) \ + $(call intermediate_targets, .dtbo.o, .dtbo.S .dtbo) -- cgit v1.3.1