diff options
Diffstat (limited to 'arch/x86/kernel/ftrace.c')
| -rw-r--r-- | arch/x86/kernel/ftrace.c | 38 |
1 files changed, 11 insertions, 27 deletions
diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c index c39f906cdc4e..bd165004776d 100644 --- a/arch/x86/kernel/ftrace.c +++ b/arch/x86/kernel/ftrace.c @@ -37,7 +37,7 @@ static int ftrace_poke_late = 0; -int ftrace_arch_code_modify_prepare(void) +void ftrace_arch_code_modify_prepare(void) __acquires(&text_mutex) { /* @@ -47,10 +47,9 @@ int ftrace_arch_code_modify_prepare(void) */ mutex_lock(&text_mutex); ftrace_poke_late = 1; - return 0; } -int ftrace_arch_code_modify_post_process(void) +void ftrace_arch_code_modify_post_process(void) __releases(&text_mutex) { /* @@ -61,7 +60,6 @@ int ftrace_arch_code_modify_post_process(void) text_poke_finish(); ftrace_poke_late = 0; mutex_unlock(&text_mutex); - return 0; } static const char *ftrace_nop_replace(void) @@ -93,6 +91,7 @@ static int ftrace_verify_code(unsigned long ip, const char *old_code) /* Make sure it is what we expect it to be */ if (memcmp(cur_code, old_code, MCOUNT_INSN_SIZE) != 0) { + ftrace_expected = old_code; WARN_ON(1); return -EINVAL; } @@ -303,7 +302,7 @@ union ftrace_op_code_union { } __attribute__((packed)); }; -#define RET_SIZE 1 +#define RET_SIZE (IS_ENABLED(CONFIG_RETPOLINE) ? 5 : 1 + IS_ENABLED(CONFIG_SLS)) static unsigned long create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) @@ -316,12 +315,12 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) unsigned long offset; unsigned long npages; unsigned long size; - unsigned long retq; unsigned long *ptr; void *trampoline; void *ip; /* 48 8b 15 <offset> is movq <offset>(%rip), %rdx */ unsigned const char op_ref[] = { 0x48, 0x8b, 0x15 }; + unsigned const char retq[] = { RET_INSN_OPCODE, INT3_INSN_OPCODE }; union ftrace_op_code_union op_ptr; int ret; @@ -359,12 +358,10 @@ create_trampoline(struct ftrace_ops *ops, unsigned int *tramp_size) goto fail; ip = trampoline + size; - - /* The trampoline ends with ret(q) */ - retq = (unsigned long)ftrace_stub; - ret = copy_from_kernel_nofault(ip, (void *)retq, RET_SIZE); - if (WARN_ON(ret < 0)) - goto fail; + if (cpu_feature_enabled(X86_FEATURE_RETHUNK)) + __text_gen_insn(ip, JMP32_INSN_OPCODE, ip, &__x86_return_thunk, JMP32_INSN_SIZE); + else + memcpy(ip, retq, sizeof(retq)); /* No need to test direct calls on created trampolines */ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS) { @@ -584,9 +581,7 @@ void arch_ftrace_trampoline_free(struct ftrace_ops *ops) #ifdef CONFIG_FUNCTION_GRAPH_TRACER -#ifdef CONFIG_DYNAMIC_FTRACE - -#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS +#if defined(CONFIG_DYNAMIC_FTRACE) && !defined(CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS) extern void ftrace_graph_call(void); static const char *ftrace_jmp_replace(unsigned long ip, unsigned long addr) { @@ -615,18 +610,7 @@ int ftrace_disable_ftrace_graph_caller(void) return ftrace_mod_jmp(ip, &ftrace_stub); } -#else /* !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ -int ftrace_enable_ftrace_graph_caller(void) -{ - return 0; -} - -int ftrace_disable_ftrace_graph_caller(void) -{ - return 0; -} -#endif /* CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ -#endif /* !CONFIG_DYNAMIC_FTRACE */ +#endif /* CONFIG_DYNAMIC_FTRACE && !CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS */ /* * Hook the return address and push it in the stack of return addrs |