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/arch/xtensa/include/asm/barrier.h | 18 ++++++++++++ tools/arch/xtensa/include/uapi/asm/mman.h | 46 +++++++++++++++++++++++++++++++ 2 files changed, 64 insertions(+) create mode 100644 tools/arch/xtensa/include/asm/barrier.h create mode 100644 tools/arch/xtensa/include/uapi/asm/mman.h (limited to 'tools/arch/xtensa/include') diff --git a/tools/arch/xtensa/include/asm/barrier.h b/tools/arch/xtensa/include/asm/barrier.h new file mode 100644 index 000000000..583800bd7 --- /dev/null +++ b/tools/arch/xtensa/include/asm/barrier.h @@ -0,0 +1,18 @@ +/* + * Copied from the kernel sources to tools/: + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * Copyright (C) 2001 - 2012 Tensilica Inc. + */ + +#ifndef _TOOLS_LINUX_XTENSA_SYSTEM_H +#define _TOOLS_LINUX_XTENSA_SYSTEM_H + +#define mb() ({ __asm__ __volatile__("memw" : : : "memory"); }) +#define rmb() barrier() +#define wmb() mb() + +#endif /* _TOOLS_LINUX_XTENSA_SYSTEM_H */ diff --git a/tools/arch/xtensa/include/uapi/asm/mman.h b/tools/arch/xtensa/include/uapi/asm/mman.h new file mode 100644 index 000000000..f2b08c990 --- /dev/null +++ b/tools/arch/xtensa/include/uapi/asm/mman.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ +#ifndef TOOLS_ARCH_XTENSA_UAPI_ASM_MMAN_FIX_H +#define TOOLS_ARCH_XTENSA_UAPI_ASM_MMAN_FIX_H +#define MADV_DODUMP 17 +#define MADV_DOFORK 11 +#define MADV_DONTDUMP 16 +#define MADV_DONTFORK 10 +#define MADV_DONTNEED 4 +#define MADV_FREE 8 +#define MADV_HUGEPAGE 14 +#define MADV_MERGEABLE 12 +#define MADV_NOHUGEPAGE 15 +#define MADV_NORMAL 0 +#define MADV_RANDOM 1 +#define MADV_REMOVE 9 +#define MADV_SEQUENTIAL 2 +#define MADV_UNMERGEABLE 13 +#define MADV_WILLNEED 3 +#define MAP_ANONYMOUS 0x0800 +#define MAP_DENYWRITE 0x2000 +#define MAP_EXECUTABLE 0x4000 +#define MAP_FILE 0 +#define MAP_FIXED 0x010 +#define MAP_GROWSDOWN 0x1000 +#define MAP_HUGETLB 0x80000 +#define MAP_LOCKED 0x8000 +#define MAP_NONBLOCK 0x20000 +#define MAP_NORESERVE 0x0400 +#define MAP_POPULATE 0x10000 +#define MAP_STACK 0x40000 +#define PROT_EXEC 0x4 +#define PROT_GROWSDOWN 0x01000000 +#define PROT_GROWSUP 0x02000000 +#define PROT_NONE 0x0 +#define PROT_READ 0x1 +#define PROT_SEM 0x10 +#define PROT_WRITE 0x2 +/* MADV_HWPOISON is undefined on xtensa, fix it for perf */ +#define MADV_HWPOISON 100 +/* MADV_SOFT_OFFLINE is undefined on xtensa, fix it for perf */ +#define MADV_SOFT_OFFLINE 101 +/* MAP_32BIT is undefined on xtensa, fix it for perf */ +#define MAP_32BIT 0 +/* MAP_UNINITIALIZED is undefined on xtensa, fix it for perf */ +#define MAP_UNINITIALIZED 0 +#endif -- cgit v1.3.1