Re: ext4_lazyinit_thread: 'ret' may be used uninitialized in thisfunction

From: Ted Ts'o
Date: Tue Nov 02 2010 - 14:29:37 EST


On Mon, Nov 01, 2010 at 04:27:26PM +0100, Lukas Czerner wrote:
>
> thank you for noticing this, because I actually do not see the warning
> (I wonder why...), but it is definitely a bug, so the trivial patch below
> should fix that.

This is a slightly less trivial fix that eliminates the need for the
"ret" variable entirely.

- Ted

commit e048924538f0c62d18306e2fea0e22dac0140f6e
Author: Theodore Ts'o <tytso@xxxxxxx>
Date: Tue Nov 2 14:19:30 2010 -0400

ext4: "ret" may be used uninitialized in ext4_lazyinit_thread()

Newer GCC's reported the following build warning:

fs/ext4/super.c: In function 'ext4_lazyinit_thread':
fs/ext4/super.c:2702: warning: 'ret' may be used uninitialized in this function

Fix it by removing the need for the ret variable in the first place.

Signed-off-by: "Lukas Czerner" <lczerner@xxxxxxxxxx>
Reported-by: "Stefan Richter" <stefanr@xxxxxxxxxxxxxxxxx>
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 8d1d942..4d7ef31 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2699,7 +2699,6 @@ static int ext4_lazyinit_thread(void *arg)
struct ext4_li_request *elr;
unsigned long next_wakeup;
DEFINE_WAIT(wait);
- int ret;

BUG_ON(NULL == eli);

@@ -2723,13 +2722,12 @@ cont_thread:
elr = list_entry(pos, struct ext4_li_request,
lr_request);

- if (time_after_eq(jiffies, elr->lr_next_sched))
- ret = ext4_run_li_request(elr);
-
- if (ret) {
- ret = 0;
- ext4_remove_li_request(elr);
- continue;
+ if (time_after_eq(jiffies, elr->lr_next_sched)) {
+ if (ext4_run_li_request(elr) != 0) {
+ /* error, remove the lazy_init job */
+ ext4_remove_li_request(elr);
+ continue;
+ }
}

if (time_before(elr->lr_next_sched, next_wakeup))
--
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