As warned by smatch:
drivers/media/pci/mantis/mantis_uart.c:105 mantis_uart_work() warn: this loop depends on readl() succeeding
If something goes wrong at readl(), the logic will stay there
inside an IRQ code forever. This is not the nicest thing to
do :-)
So, add a timeout there, preventing staying inside the IRQ
for more than 10ms.
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
---
drivers/media/pci/mantis/mantis_uart.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/media/pci/mantis/mantis_uart.c b/drivers/media/pci/mantis/mantis_uart.c
index 18f81c135996..b7765687e0c3 100644
--- a/drivers/media/pci/mantis/mantis_uart.c
+++ b/drivers/media/pci/mantis/mantis_uart.c
@@ -92,6 +92,7 @@ static void mantis_uart_work(struct work_struct *work)
{
struct mantis_pci *mantis = container_of(work, struct mantis_pci, uart_work);
u32 stat;
+ unsigned long timeout;
stat = mmread(MANTIS_UART_STAT);
@@ -102,9 +103,15 @@ static void mantis_uart_work(struct work_struct *work)
* MANTIS_UART_RXFIFO_DATA is only set if at least
* config->bytes + 1 bytes are in the FIFO.
*/
+
+ /* FIXME: is 10ms good enough ? */
+ timeout = jiffies + msecs_to_jiffies(10);
while (stat & MANTIS_UART_RXFIFO_DATA) {
mantis_uart_read(mantis);
stat = mmread(MANTIS_UART_STAT);
+
+ if (!time_is_after_jiffies(timeout))
+ break;
}
/* re-enable UART (RX) interrupt */
--
2.14.3
