tracing: Do not reset *pos in set_ftrace_filter
After the filtered functions are read, the probed functions are read
from the hash in set_ftrace_filter. When the hashed probed functions
are read, the *pos passed in is reset. Instead of modifying the pos
given to the read function, just record the pos where the filtered
functions ended and subtract from that.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index fa7ece6..585ea27 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1368,6 +1368,7 @@
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
struct ftrace_iterator {
+ loff_t func_pos;
struct ftrace_page *pg;
int hidx;
int idx;
@@ -1418,12 +1419,15 @@
loff_t l;
if (!(iter->flags & FTRACE_ITER_HASH))
- *pos = 0;
+ iter->func_pos = *pos;
+
+ if (iter->func_pos > *pos)
+ return NULL;
iter->flags |= FTRACE_ITER_HASH;
iter->hidx = 0;
- for (l = 0; l <= *pos; ) {
+ for (l = 0; l <= (*pos - iter->func_pos); ) {
p = t_hash_next(m, p, &l);
if (!p)
break;