[PATCH v3] kdb: remove unnecessary null check of dbg_io_ops

From: Cengiz Can
Date: Tue Jun 30 2020 - 04:30:16 EST


`kdb_msg_write` operates on a global `struct kgdb_io *` called
`dbg_io_ops`.

It's initialized in `debug_core.c` and checked throughout the debug
flow.

There's a null check in `kdb_msg_write` which triggers static analyzers
and gives the (almost entirely wrong) impression that it can be null.

Coverity scanner caught this as CID 1465042.

I have removed the unnecessary null check and eliminated false-positive
forward null dereference warning.

Signed-off-by: Cengiz Can <cengiz@xxxxxxxxxx>
---
kernel/debug/kdb/kdb_io.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/kernel/debug/kdb/kdb_io.c b/kernel/debug/kdb/kdb_io.c
index 683a799618ad..81783ecaec58 100644
--- a/kernel/debug/kdb/kdb_io.c
+++ b/kernel/debug/kdb/kdb_io.c
@@ -545,18 +545,18 @@ static int kdb_search_string(char *searched, char *searchfor)
static void kdb_msg_write(const char *msg, int msg_len)
{
struct console *c;
+ const char *cp;
+ int len;

if (msg_len == 0)
return;

- if (dbg_io_ops) {
- const char *cp = msg;
- int len = msg_len;
+ cp = msg;
+ len = msg_len;

- while (len--) {
- dbg_io_ops->write_char(*cp);
- cp++;
- }
+ while (len--) {
+ dbg_io_ops->write_char(*cp);
+ cp++;
}

for_each_console(c) {
--
2.27.0