[PATCH v8 13/17] x86/ftrace: enable dynamic ftrace without CONFIG_MODULES
From: Mike Rapoport <rppt@kernel.org>
Date: 2024-05-05 14:28:58
Also in:
bpf, linux-arch, linux-arm-kernel, linux-mips, linux-mm, linux-modules, linux-riscv, linux-s390, linuxppc-dev, lkml, loongarch, netdev, sparclinux
Subsystem:
function hooks (ftrace), the rest, x86 architecture (32-bit and 64-bit) · Maintainers:
Steven Rostedt, Masami Hiramatsu, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen
From: "Mike Rapoport (IBM)" <rppt@kernel.org> Dynamic ftrace must allocate memory for code and this was impossible without CONFIG_MODULES. With execmem separated from the modules code, execmem_text_alloc() is available regardless of CONFIG_MODULES. Remove dependency of dynamic ftrace on CONFIG_MODULES and make CONFIG_DYNAMIC_FTRACE select CONFIG_EXECMEM in Kconfig. Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> --- arch/x86/Kconfig | 1 + arch/x86/kernel/ftrace.c | 10 ---------- 2 files changed, 1 insertion(+), 10 deletions(-)
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 4474bf32d0a4..f2917ccf4fb4 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig@@ -34,6 +34,7 @@ config X86_64 select SWIOTLB select ARCH_HAS_ELFCORE_COMPAT select ZONE_DMA32 + select EXECMEM if DYNAMIC_FTRACE config FORCE_DYNAMIC_FTRACE def_bool y
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index c8ddb7abda7c..8da0e66ca22d 100644
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c@@ -261,8 +261,6 @@ void arch_ftrace_update_code(int command) /* Currently only x86_64 supports dynamic trampolines */ #ifdef CONFIG_X86_64 -#ifdef CONFIG_MODULES -/* Module allocation simplifies allocating memory for code */ static inline void *alloc_tramp(unsigned long size) { return execmem_alloc(EXECMEM_FTRACE, size);
@@ -271,14 +269,6 @@ static inline void tramp_free(void *tramp) { execmem_free(tramp); } -#else -/* Trampolines can only be created if modules are supported */ -static inline void *alloc_tramp(unsigned long size) -{ - return NULL; -} -static inline void tramp_free(void *tramp) { } -#endif /* Defined as markers to the end of the ftrace default trampolines */ extern void ftrace_regs_caller_end(void);
--
2.43.0