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.compiler | 93 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 93 insertions(+) create mode 100644 scripts/Makefile.compiler (limited to 'scripts/Makefile.compiler') diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler new file mode 100644 index 000000000..06bbe29c8 --- /dev/null +++ b/scripts/Makefile.compiler @@ -0,0 +1,93 @@ +# SPDX-License-Identifier: GPL-2.0-only + +# cc-cross-prefix +# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-) +# Return first where a gcc is found in PATH. +# If no gcc found in PATH with listed prefixes return nothing +# +# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it +# would try to directly execute the shell builtin 'command'. This workaround +# should be kept for a long time since this issue was fixed only after the +# GNU Make 4.2.1 release. +cc-cross-prefix = $(firstword $(foreach c, $(1), \ + $(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c)))) + +# output directory for tests below +TMPOUT = .tmp_$$$$ + +# try-run +# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise) +# Exit code chooses option. "$$TMP" serves as a temporary file and is +# automatically cleaned up. +try-run = $(shell set -e; \ + TMP=$(TMPOUT)/tmp; \ + trap "rm -rf $(TMPOUT)" EXIT; \ + mkdir -p $(TMPOUT); \ + if ($(1)) >/dev/null 2>&1; \ + then echo "$(2)"; \ + else echo "$(3)"; \ + fi) + +# as-option +# Usage: aflags-y += $(call as-option,-Wa$(comma)-isa=foo,) + +as-option = $(call try-run,\ + $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) $(1) -c -x assembler-with-cpp /dev/null -o "$$TMP",$(1),$(2)) + +# as-instr +# Usage: aflags-y += $(call as-instr,instr,option1,option2) + +as-instr = $(call try-run,\ + printf "%b\n" "$(1)" | $(CC) -Werror $(CLANG_FLAGS) $(KBUILD_AFLAGS) -Wa$(comma)--fatal-warnings -c -x assembler-with-cpp -o "$$TMP" -,$(2),$(3)) + +# __cc-option +# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586) +__cc-option = $(call try-run,\ + $(1) -Werror $(2) $(3:-Wno-%=-W%) -c -x c /dev/null -o "$$TMP",$(3),$(4)) + +# cc-option +# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586) + +cc-option = $(call __cc-option, $(CC),\ + $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2)) + +# cc-option-yn +# Usage: flag := $(call cc-option-yn,-march=winchip-c6) +cc-option-yn = $(if $(call cc-option,$1),y,n) + +# cc-disable-warning +# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) +cc-disable-warning = $(call cc-option,-Wno-$(strip $1)) + +# gcc-min-version +# Usage: cflags-$(call gcc-min-version, 110100) += -foo +gcc-min-version = $(call test-ge, $(CONFIG_GCC_VERSION), $1) + +# clang-min-version +# Usage: cflags-$(call clang-min-version, 110000) += -foo +clang-min-version = $(call test-ge, $(CONFIG_CLANG_VERSION), $1) + +# rustc-min-version +# Usage: rustc-$(call rustc-min-version, 108500) += -Cfoo +rustc-min-version = $(call test-ge, $(CONFIG_RUSTC_VERSION), $1) + +# ld-option +# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y) +ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3)) + +# __rustc-option +# Usage: MY_RUSTFLAGS += $(call __rustc-option,$(RUSTC),$(MY_RUSTFLAGS),-Cinstrument-coverage,-Zinstrument-coverage) +# TODO: remove RUSTC_BOOTSTRAP=1 when we raise the minimum GNU Make version to 4.4 +__rustc-option = $(call try-run,\ + echo '$(pound)![allow(missing_docs)]$(pound)![feature(no_core)]$(pound)![no_core]' | RUSTC_BOOTSTRAP=1\ + $(1) --sysroot=/dev/null $(KBUILD_RUSTFLAGS_OPTION_CHKS) $(filter-out --sysroot=/dev/null --target=%target.json,$(2)) $(3)\ + --crate-type=rlib --out-dir=$(TMPOUT) --emit=obj=- - >/dev/null,$(3),$(4)) + +# rustc-option +# Usage: rustflags-y += $(call rustc-option,-Cinstrument-coverage,-Zinstrument-coverage) +rustc-option = $(call __rustc-option, $(RUSTC),\ + $(KBUILD_RUSTFLAGS),$(1),$(2)) + +# rustc-option-yn +# Usage: flag := $(call rustc-option-yn,-Cinstrument-coverage) +rustc-option-yn = $(if $(call rustc-option,$1),y,n) -- cgit v1.3.1