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 --- tools/build/tests/ex/Build | 11 ++++++ tools/build/tests/ex/Makefile | 27 +++++++++++++++ tools/build/tests/ex/a.c | 6 ++++ tools/build/tests/ex/arch/Build | 2 ++ tools/build/tests/ex/arch/e.c | 6 ++++ tools/build/tests/ex/arch/f.c | 6 ++++ tools/build/tests/ex/b.c | 6 ++++ tools/build/tests/ex/c.c | 6 ++++ tools/build/tests/ex/d.c | 6 ++++ tools/build/tests/ex/empty/Build | 0 tools/build/tests/ex/empty2/README | 2 ++ tools/build/tests/ex/ex.c | 22 ++++++++++++ tools/build/tests/ex/inc.c | 9 +++++ tools/build/tests/run.sh | 70 ++++++++++++++++++++++++++++++++++++++ 14 files changed, 179 insertions(+) create mode 100644 tools/build/tests/ex/Build create mode 100644 tools/build/tests/ex/Makefile create mode 100644 tools/build/tests/ex/a.c create mode 100644 tools/build/tests/ex/arch/Build create mode 100644 tools/build/tests/ex/arch/e.c create mode 100644 tools/build/tests/ex/arch/f.c create mode 100644 tools/build/tests/ex/b.c create mode 100644 tools/build/tests/ex/c.c create mode 100644 tools/build/tests/ex/d.c create mode 100644 tools/build/tests/ex/empty/Build create mode 100644 tools/build/tests/ex/empty2/README create mode 100644 tools/build/tests/ex/ex.c create mode 100644 tools/build/tests/ex/inc.c create mode 100755 tools/build/tests/run.sh (limited to 'tools/build/tests') diff --git a/tools/build/tests/ex/Build b/tools/build/tests/ex/Build new file mode 100644 index 000000000..4d502f9b1 --- /dev/null +++ b/tools/build/tests/ex/Build @@ -0,0 +1,11 @@ +ex-y += ex.o +ex-y += a.o +ex-y += b.o +ex-y += b.o +ex-y += empty/ +ex-y += empty2/ +ex-y += inc.o + +libex-y += c.o +libex-y += d.o +libex-y += arch/ diff --git a/tools/build/tests/ex/Makefile b/tools/build/tests/ex/Makefile new file mode 100644 index 000000000..fee032e06 --- /dev/null +++ b/tools/build/tests/ex/Makefile @@ -0,0 +1,27 @@ +# SPDX-License-Identifier: GPL-2.0 +export srctree := $(abspath ../../../..) +export CC := gcc +export LD := ld +export AR := ar + +ex: + +include $(srctree)/tools/build/Makefile.include + +ex: ex-in.o libex-in.o + $(CC) -o $@ $^ + +ex.%: fixdep FORCE + make -f $(srctree)/tools/build/Makefile.build dir=. $@ + +ex-in.o: fixdep FORCE + make $(build)=ex + +libex-in.o: fixdep FORCE + make $(build)=libex + +clean: + find . -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete + rm -f ex ex.i ex.s + +.PHONY: FORCE diff --git a/tools/build/tests/ex/a.c b/tools/build/tests/ex/a.c new file mode 100644 index 000000000..66017a9f4 --- /dev/null +++ b/tools/build/tests/ex/a.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int a(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/arch/Build b/tools/build/tests/ex/arch/Build new file mode 100644 index 000000000..55506189e --- /dev/null +++ b/tools/build/tests/ex/arch/Build @@ -0,0 +1,2 @@ +libex-y += e.o +libex-y += f.o diff --git a/tools/build/tests/ex/arch/e.c b/tools/build/tests/ex/arch/e.c new file mode 100644 index 000000000..f6ef585b5 --- /dev/null +++ b/tools/build/tests/ex/arch/e.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int e(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/arch/f.c b/tools/build/tests/ex/arch/f.c new file mode 100644 index 000000000..bffd9c67e --- /dev/null +++ b/tools/build/tests/ex/arch/f.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int f(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/b.c b/tools/build/tests/ex/b.c new file mode 100644 index 000000000..2b29fb4d3 --- /dev/null +++ b/tools/build/tests/ex/b.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int b(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/c.c b/tools/build/tests/ex/c.c new file mode 100644 index 000000000..a63b20ab8 --- /dev/null +++ b/tools/build/tests/ex/c.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int c(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/d.c b/tools/build/tests/ex/d.c new file mode 100644 index 000000000..e114e8dca --- /dev/null +++ b/tools/build/tests/ex/d.c @@ -0,0 +1,6 @@ +// SPDX-License-Identifier: GPL-2.0 + +int d(void) +{ + return 0; +} diff --git a/tools/build/tests/ex/empty/Build b/tools/build/tests/ex/empty/Build new file mode 100644 index 000000000..e69de29bb diff --git a/tools/build/tests/ex/empty2/README b/tools/build/tests/ex/empty2/README new file mode 100644 index 000000000..2107cc5bf --- /dev/null +++ b/tools/build/tests/ex/empty2/README @@ -0,0 +1,2 @@ +This directory is left intentionally without Build file +to test proper nesting into Build-less directories. diff --git a/tools/build/tests/ex/ex.c b/tools/build/tests/ex/ex.c new file mode 100644 index 000000000..3c02756ef --- /dev/null +++ b/tools/build/tests/ex/ex.c @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0 + +int a(void); +int b(void); +int c(void); +int d(void); +int e(void); +int f(void); +int inc(void); + +int main(void) +{ + a(); + b(); + c(); + d(); + e(); + f(); + inc(); + + return 0; +} diff --git a/tools/build/tests/ex/inc.c b/tools/build/tests/ex/inc.c new file mode 100644 index 000000000..3636ab5bf --- /dev/null +++ b/tools/build/tests/ex/inc.c @@ -0,0 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0 +#ifdef INCLUDE +#include "krava.h" +#endif + +int inc(void) +{ + return 0; +} diff --git a/tools/build/tests/run.sh b/tools/build/tests/run.sh new file mode 100755 index 000000000..2c54e4d43 --- /dev/null +++ b/tools/build/tests/run.sh @@ -0,0 +1,70 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0 + +function test_ex { + make -C ex V=1 clean > ex.out 2>&1 + make -C ex V=1 >> ex.out 2>&1 + + if [ ! -x ./ex/ex ]; then + echo FAILED + exit -1 + fi + + make -C ex V=1 clean > /dev/null 2>&1 + rm -f ex.out +} + +function test_ex_suffix { + make -C ex V=1 clean > ex.out 2>&1 + + # use -rR to disable make's builtin rules + make -rR -C ex V=1 ex.o >> ex.out 2>&1 + make -rR -C ex V=1 ex.i >> ex.out 2>&1 + make -rR -C ex V=1 ex.s >> ex.out 2>&1 + + if [ -x ./ex/ex ]; then + echo FAILED + exit -1 + fi + + if [ ! -f ./ex/ex.o -o ! -f ./ex/ex.i -o ! -f ./ex/ex.s ]; then + echo FAILED + exit -1 + fi + + make -C ex V=1 clean > /dev/null 2>&1 + rm -f ex.out +} + +function test_ex_include { + make -C ex V=1 clean > ex.out 2>&1 + + # build with krava.h include + touch ex/krava.h + make -C ex V=1 CFLAGS=-DINCLUDE >> ex.out 2>&1 + + if [ ! -x ./ex/ex ]; then + echo FAILED + exit -1 + fi + + # build without the include + rm -f ex/krava.h ex/ex + make -C ex V=1 >> ex.out 2>&1 + + if [ ! -x ./ex/ex ]; then + echo FAILED + exit -1 + fi + + make -C ex V=1 clean > /dev/null 2>&1 + rm -f ex.out +} + +echo -n Testing.. + +test_ex +test_ex_suffix +test_ex_include + +echo OK -- cgit v1.3.1