p71924506
/
linux_old1
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

media: rainshadow-cec: avoid -Wmaybe-uninitialized warning again 

Back in April I created a patch to address a false-positive warning:

drivers/media/usb/rainshadow-cec/rainshadow-cec.c: In function 'rain_irq_work_handler':
drivers/media/usb/rainshadow-cec/rainshadow-cec.c:171:31: error: 'data' may be used uninitialized in this function [-Werror=maybe-uninitialized]

My patch was totally wrong and introduced a real bug, and Colin Ian King thankfully
noticed it now and fixed my mistake. Unfortunately, fixing the actual uninitialized
data in this case brought back the original bogus warning.

This is a new version of the patch, which simplifies the code to the point where
gcc notices the behavior is correct.

Fixes: ca33784ba4 ("[media] rainshadow-cec: ensure exit_loop is intialized")
Fixes: ea6a69defd ("[media] rainshadow-cec: avoid -Wmaybe-uninitialized warning")

Cc: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hansverk@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Arnd Bergmann 2017-06-21 19:10:32 -03:00 committed by Mauro Carvalho Chehab
parent 7ee88f8c6b
commit 0a0c1b823c
1 changed files with 9 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
drivers/media/usb/rainshadow-cec/rainshadow-cec.c
View File

@ -116,21 +116,19 @@ static void rain_irq_work_handler(struct work_struct *work)
while (true) {
unsigned long flags;
bool exit_loop = false;
char data;
spin_lock_irqsave(&rain->buf_lock, flags);
if (rain->buf_len) {
data = rain->buf[rain->buf_rd_idx];
rain->buf_len--;
rain->buf_rd_idx = (rain->buf_rd_idx + 1) & 0xff;
} else {
exit_loop = true;
}
spin_unlock_irqrestore(&rain->buf_lock, flags);
if (exit_loop)
if (!rain->buf_len) {
spin_unlock_irqrestore(&rain->buf_lock, flags);
break;
}
data = rain->buf[rain->buf_rd_idx];
rain->buf_len--;
rain->buf_rd_idx = (rain->buf_rd_idx + 1) & 0xff;
spin_unlock_irqrestore(&rain->buf_lock, flags);
if (!rain->cmd_started && data != '?')
continue;