diff options
| author | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2018-04-12 08:28:33 -0400 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2018-04-17 05:50:05 -0400 |
| commit | cac61a1acb1def146c3900f1c8f7af4947d98814 (patch) | |
| tree | e5658832786cc7024d32d7c22f616a5e3a9caecd | |
| parent | ee2d243d6beea21e79631fa3442e92ad0fa11a6a (diff) | |
media: mantis: prevent staying forever in a loop at IRQ
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@s-opensource.com>
| -rw-r--r-- | drivers/media/pci/mantis/mantis_uart.c | 7 |
1 files changed, 7 insertions, 0 deletions
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 */ |