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.asm-headers | 105 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 105 insertions(+) create mode 100644 scripts/Makefile.asm-headers (limited to 'scripts/Makefile.asm-headers') diff --git a/scripts/Makefile.asm-headers b/scripts/Makefile.asm-headers new file mode 100644 index 000000000..b38931314 --- /dev/null +++ b/scripts/Makefile.asm-headers @@ -0,0 +1,105 @@ +# SPDX-License-Identifier: GPL-2.0 +# include/asm-generic contains a lot of files that are used +# verbatim by several architectures. +# +# This Makefile generates arch/$(SRCARCH)/include/generated/(uapi/)/asm +# headers from multiple sources: +# - a small wrapper to include the corresponding asm-generic/*.h +# is generated for each file listed as generic-y +# - uapi/asm/unistd_*.h files listed as syscalls-y are generated from +# syscall.tbl with the __NR_* macros +# - Corresponding asm/syscall_table_*.h are generated from the same input + +PHONY := all +all: + +src := $(srctree)/$(subst /generated,,$(obj)) + +syscall_abis_32 += common,32 +syscall_abis_64 += common,64 +syscalltbl := $(srctree)/scripts/syscall.tbl +syshdr-args := --emit-nr + +# let architectures override $(syscall_abis_%) and $(syscalltbl) +-include $(srctree)/arch/$(SRCARCH)/kernel/Makefile.syscalls +include $(srctree)/scripts/Kbuild.include +-include $(kbuild-file) + +syshdr := $(srctree)/scripts/syscallhdr.sh +systbl := $(srctree)/scripts/syscalltbl.sh + +# $(generic)/Kbuild lists mandatory-y. Exclude um since it is a special case. +ifneq ($(SRCARCH),um) +include $(srctree)/$(generic)/Kbuild +endif + +redundant := $(filter $(mandatory-y) $(generated-y), $(generic-y)) +redundant += $(foreach f, $(generic-y), $(if $(wildcard $(src)/$(f)),$(f))) +redundant := $(sort $(redundant)) +$(if $(redundant),\ + $(warning redundant generic-y found in $(src)/Kbuild: $(redundant))) + +# If arch does not implement mandatory headers, fallback to asm-generic ones. +mandatory-y := $(filter-out $(generated-y), $(mandatory-y)) +generic-y += $(foreach f, $(mandatory-y), $(if $(wildcard $(src)/$(f)),,$(f))) + +generic-y := $(addprefix $(obj)/, $(generic-y)) +syscall-y := $(addprefix $(obj)/, $(syscall-y)) +generated-y := $(addprefix $(obj)/, $(generated-y)) + +# Remove stale wrappers when the corresponding files are removed from generic-y +old-headers := $(shell test -d $(obj) && find $(obj) -name *.h) +unwanted := $(filter-out $(generic-y) $(generated-y) $(syscall-y),$(old-headers)) + +filechk_wrap = echo "\#include " + +quiet_cmd_remove = REMOVE $(unwanted) + cmd_remove = rm -f $(unwanted); find $(obj) -type d -empty -delete + +quiet_cmd_syshdr = SYSHDR $@ + cmd_syshdr = $(CONFIG_SHELL) $(syshdr) \ + $(if $(syshdr-args-$*),$(syshdr-args-$*),$(syshdr-args)) \ + $(if $(syscall_compat),--prefix "compat$*_") \ + --abis $(subst $(space),$(comma),$(strip $(syscall_abis_$*))) \ + $< $@ + +quiet_cmd_systbl = SYSTBL $@ + cmd_systbl = $(CONFIG_SHELL) $(systbl) \ + $(if $(systbl-args-$*),$(systbl-args-$*),$(systbl-args)) \ + --abis $(subst $(space),$(comma),$(strip $(syscall_abis_$*))) \ + $< $@ + +all: $(generic-y) $(syscall-y) + $(if $(unwanted),$(call cmd,remove)) + @: + +$(obj)/%.h: $(srctree)/$(generic)/%.h FORCE + $(call filechk,wrap) + +$(obj)/unistd_%.h: $(syscalltbl) $(syshdr) FORCE + $(call if_changed,syshdr) + +$(obj)/unistd_compat_%.h: syscall_compat:=1 +$(obj)/unistd_compat_%.h: $(syscalltbl) $(syshdr) FORCE + $(call if_changed,syshdr) + +$(obj)/syscall_table_%.h: $(syscalltbl) $(systbl) FORCE + $(call if_changed,systbl) + +targets := $(syscall-y) + +# Create output directory. Skip it if at least one old header exists +# since we know the output directory already exists. +ifeq ($(old-headers),) +$(shell mkdir -p $(obj)) +endif + +PHONY += FORCE + +FORCE: + +existing-targets := $(wildcard $(sort $(targets))) + +-include $(foreach f,$(existing-targets),$(dir $(f)).$(notdir $(f)).cmd) + +.PHONY: $(PHONY) -- cgit v1.3.1