diff options
Diffstat (limited to 'arch/riscv/kernel/ftrace.c')
-rw-r--r-- | arch/riscv/kernel/ftrace.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/arch/riscv/kernel/ftrace.c b/arch/riscv/kernel/ftrace.c index 5bff37af4770..03a6434a8cdd 100644 --- a/arch/riscv/kernel/ftrace.c +++ b/arch/riscv/kernel/ftrace.c @@ -15,10 +15,19 @@ void ftrace_arch_code_modify_prepare(void) __acquires(&text_mutex) { mutex_lock(&text_mutex); + + /* + * The code sequences we use for ftrace can't be patched while the + * kernel is running, so we need to use stop_machine() to modify them + * for now. This doesn't play nice with text_mutex, we use this flag + * to elide the check. + */ + riscv_patch_in_stop_machine = true; } void ftrace_arch_code_modify_post_process(void) __releases(&text_mutex) { + riscv_patch_in_stop_machine = false; mutex_unlock(&text_mutex); } @@ -107,9 +116,9 @@ int ftrace_init_nop(struct module *mod, struct dyn_ftrace *rec) { int out; - ftrace_arch_code_modify_prepare(); + mutex_lock(&text_mutex); out = ftrace_make_nop(mod, rec, MCOUNT_ADDR); - ftrace_arch_code_modify_post_process(); + mutex_unlock(&text_mutex); return out; } |