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/include/asm/alternative.h | 19 ++++++++++++ tools/include/asm/atomic.h | 11 +++++++ tools/include/asm/barrier.h | 65 +++++++++++++++++++++++++++++++++++++++++ tools/include/asm/bug.h | 46 +++++++++++++++++++++++++++++ tools/include/asm/export.h | 7 +++++ tools/include/asm/io.h | 11 +++++++ tools/include/asm/rwonce.h | 0 tools/include/asm/sections.h | 4 +++ tools/include/asm/timex.h | 13 +++++++++ 9 files changed, 176 insertions(+) create mode 100644 tools/include/asm/alternative.h create mode 100644 tools/include/asm/atomic.h create mode 100644 tools/include/asm/barrier.h create mode 100644 tools/include/asm/bug.h create mode 100644 tools/include/asm/export.h create mode 100644 tools/include/asm/io.h create mode 100644 tools/include/asm/rwonce.h create mode 100644 tools/include/asm/sections.h create mode 100644 tools/include/asm/timex.h (limited to 'tools/include/asm') diff --git a/tools/include/asm/alternative.h b/tools/include/asm/alternative.h new file mode 100644 index 000000000..8e548ac8f --- /dev/null +++ b/tools/include/asm/alternative.h @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TOOLS_ASM_ALTERNATIVE_ASM_H +#define _TOOLS_ASM_ALTERNATIVE_ASM_H + +#if defined(__s390x__) +#ifdef __ASSEMBLY__ +.macro ALTERNATIVE oldinstr, newinstr, feature + \oldinstr +.endm +#endif +#else + +/* Just disable it so we can build arch/x86/lib/memcpy_64.S for perf bench: */ + +#define ALTERNATIVE # + +#endif + +#endif diff --git a/tools/include/asm/atomic.h b/tools/include/asm/atomic.h new file mode 100644 index 000000000..8c9bfffd4 --- /dev/null +++ b/tools/include/asm/atomic.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __TOOLS_LINUX_ASM_ATOMIC_H +#define __TOOLS_LINUX_ASM_ATOMIC_H + +#if defined(__i386__) || defined(__x86_64__) +#include "../../arch/x86/include/asm/atomic.h" +#else +#include +#endif + +#endif /* __TOOLS_LINUX_ASM_ATOMIC_H */ diff --git a/tools/include/asm/barrier.h b/tools/include/asm/barrier.h new file mode 100644 index 000000000..0c21678ac --- /dev/null +++ b/tools/include/asm/barrier.h @@ -0,0 +1,65 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#include +#if defined(__i386__) || defined(__x86_64__) +#include "../../arch/x86/include/asm/barrier.h" +#elif defined(__arm__) +#include "../../arch/arm/include/asm/barrier.h" +#elif defined(__aarch64__) +#include "../../arch/arm64/include/asm/barrier.h" +#elif defined(__powerpc__) +#include "../../arch/powerpc/include/asm/barrier.h" +#elif defined(__riscv) +#include "../../arch/riscv/include/asm/barrier.h" +#elif defined(__s390__) +#include "../../arch/s390/include/asm/barrier.h" +#elif defined(__sh__) +#include "../../arch/sh/include/asm/barrier.h" +#elif defined(__sparc__) +#include "../../arch/sparc/include/asm/barrier.h" +#elif defined(__tile__) +#include "../../arch/tile/include/asm/barrier.h" +#elif defined(__alpha__) +#include "../../arch/alpha/include/asm/barrier.h" +#elif defined(__mips__) +#include "../../arch/mips/include/asm/barrier.h" +#elif defined(__ia64__) +#include "../../arch/ia64/include/asm/barrier.h" +#elif defined(__xtensa__) +#include "../../arch/xtensa/include/asm/barrier.h" +#else +#include +#endif + +/* + * Generic fallback smp_*() definitions for archs that haven't + * been updated yet. + */ + +#ifndef smp_rmb +# define smp_rmb() rmb() +#endif + +#ifndef smp_wmb +# define smp_wmb() wmb() +#endif + +#ifndef smp_mb +# define smp_mb() mb() +#endif + +#ifndef smp_store_release +# define smp_store_release(p, v) \ +do { \ + smp_mb(); \ + WRITE_ONCE(*p, v); \ +} while (0) +#endif + +#ifndef smp_load_acquire +# define smp_load_acquire(p) \ +({ \ + typeof(*p) ___p1 = READ_ONCE(*p); \ + smp_mb(); \ + ___p1; \ +}) +#endif diff --git a/tools/include/asm/bug.h b/tools/include/asm/bug.h new file mode 100644 index 000000000..550223f0a --- /dev/null +++ b/tools/include/asm/bug.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TOOLS_ASM_BUG_H +#define _TOOLS_ASM_BUG_H + +#include +#include + +#define __WARN_printf(arg...) do { fprintf(stderr, arg); } while (0) + +#define WARN(condition, format...) ({ \ + int __ret_warn_on = !!(condition); \ + if (unlikely(__ret_warn_on)) \ + __WARN_printf(format); \ + unlikely(__ret_warn_on); \ +}) + +#define WARN_ON(condition) ({ \ + int __ret_warn_on = !!(condition); \ + if (unlikely(__ret_warn_on)) \ + __WARN_printf("assertion failed at %s:%d\n", \ + __FILE__, __LINE__); \ + unlikely(__ret_warn_on); \ +}) + +#define WARN_ON_ONCE(condition) ({ \ + static int __warned; \ + int __ret_warn_once = !!(condition); \ + \ + if (unlikely(__ret_warn_once && !__warned)) { \ + __warned = true; \ + WARN_ON(1); \ + } \ + unlikely(__ret_warn_once); \ +}) + +#define WARN_ONCE(condition, format...) ({ \ + static int __warned; \ + int __ret_warn_once = !!(condition); \ + \ + if (unlikely(__ret_warn_once)) \ + if (WARN(!__warned, format)) \ + __warned = 1; \ + unlikely(__ret_warn_once); \ +}) + +#endif /* _TOOLS_ASM_BUG_H */ diff --git a/tools/include/asm/export.h b/tools/include/asm/export.h new file mode 100644 index 000000000..2cb1a0d83 --- /dev/null +++ b/tools/include/asm/export.h @@ -0,0 +1,7 @@ +#ifndef _TOOLS_ASM_EXPORT_H +#define _TOOLS_ASM_EXPORT_H + +#define EXPORT_SYMBOL(x) +#define EXPORT_SYMBOL_GPL(x) + +#endif /* _TOOLS_ASM_EXPORT_H */ diff --git a/tools/include/asm/io.h b/tools/include/asm/io.h new file mode 100644 index 000000000..eed5066f2 --- /dev/null +++ b/tools/include/asm/io.h @@ -0,0 +1,11 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _TOOLS_ASM_IO_H +#define _TOOLS_ASM_IO_H + +#if defined(__i386__) || defined(__x86_64__) +#include "../../arch/x86/include/asm/io.h" +#else +#include +#endif + +#endif /* _TOOLS_ASM_IO_H */ diff --git a/tools/include/asm/rwonce.h b/tools/include/asm/rwonce.h new file mode 100644 index 000000000..e69de29bb diff --git a/tools/include/asm/sections.h b/tools/include/asm/sections.h new file mode 100644 index 000000000..a80643d7a --- /dev/null +++ b/tools/include/asm/sections.h @@ -0,0 +1,4 @@ +#ifndef __TOOLS_INCLUDE_LINUX_ASM_SECTIONS_H +#define __TOOLS_INCLUDE_LINUX_ASM_SECTIONS_H + +#endif /* __TOOLS_INCLUDE_LINUX_ASM_SECTIONS_H */ diff --git a/tools/include/asm/timex.h b/tools/include/asm/timex.h new file mode 100644 index 000000000..5adfe3c6d --- /dev/null +++ b/tools/include/asm/timex.h @@ -0,0 +1,13 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __TOOLS_LINUX_ASM_TIMEX_H +#define __TOOLS_LINUX_ASM_TIMEX_H + +#include + +#define cycles_t clock_t + +static inline cycles_t get_cycles(void) +{ + return clock(); +} +#endif // __TOOLS_LINUX_ASM_TIMEX_H -- cgit v1.3.1