diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index 412505d94865..60bf8a6d55ce 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1552,7 +1552,9 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end) struct ftrace_page *pg; struct dyn_ftrace *rec; struct dyn_ftrace key; + unsigned long ip = 0; + rcu_read_lock(); key.ip = start; key.flags = end; /* overload flags, as it is unsigned long */ @@ -1565,10 +1567,13 @@ unsigned long ftrace_location_range(unsigned long start, unsigned long end) sizeof(struct dyn_ftrace), ftrace_cmp_recs); if (rec) - return rec->ip; + { + ip = rec->ip; + break; + } } - - return 0; + rcu_read_unlock(); + return ip; } /** @@ -5736,6 +5741,8 @@ static int ftrace_process_locs(struct module *mod, /* We should have used all pages unless we skipped some */ if (pg_unuse) { WARN_ON(!skipped); + /* Need to synchronize with ftrace_location_range() */ + synchronize_rcu(); ftrace_free_pages(pg_unuse); } return ret; @@ -5889,6 +5896,9 @@ void ftrace_release_mod(struct module *mod) out_unlock: mutex_unlock(&ftrace_lock); + /* Need to synchronize with ftrace_location_range() */ + if (tmp_page) + synchronize_rcu(); for (pg = tmp_page; pg; pg = tmp_page) { /* Needs to be called outside of ftrace_lock */ @@ -6196,6 +6206,7 @@ void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) unsigned long start = (unsigned long)(start_ptr); unsigned long end = (unsigned long)(end_ptr); struct ftrace_page **last_pg = &ftrace_pages_start; + struct ftrace_page *tmp_page = NULL; struct ftrace_page *pg; struct dyn_ftrace *rec; struct dyn_ftrace key; @@ -6239,12 +6250,8 @@ void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) ftrace_update_tot_cnt--; if (!pg->index) { *last_pg = pg->next; - if (pg->records) { - free_pages((unsigned long)pg->records, pg->order); - ftrace_number_of_pages -= 1 << pg->order; - } - ftrace_number_of_groups--; - kfree(pg); + pg->next = tmp_page; + tmp_page = pg; pg = container_of(last_pg, struct ftrace_page, next); if (!(*last_pg)) ftrace_pages = pg; @@ -6261,6 +6268,11 @@ void ftrace_free_mem(struct module *mod, void *start_ptr, void *end_ptr) clear_func_from_hashes(func); kfree(func); } + /* Need to synchronize with ftrace_location_range() */ + if (tmp_page) { + synchronize_rcu(); + ftrace_free_pages(tmp_page); + } } void __init ftrace_free_init_mem(void)