| Message ID | 20230508082014.23083-2-tony@atomide.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | More console rebind changes for 8250_omap serial driver | expand |
On Mon, 8 May 2023, Tony Lindgren wrote: > If serial8250_register_8250_port() fails, the SoC can hang as the > deferred PMQoS work will still run as is not flushed and removed. > > Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") > Signed-off-by: Tony Lindgren <tony@atomide.com> > --- > drivers/tty/serial/8250/8250_omap.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c > --- a/drivers/tty/serial/8250/8250_omap.c > +++ b/drivers/tty/serial/8250/8250_omap.c > @@ -1532,7 +1532,9 @@ static int omap8250_probe(struct platform_device *pdev) > err: > pm_runtime_dont_use_autosuspend(&pdev->dev); > pm_runtime_put_sync(&pdev->dev); > + flush_work(&priv->qos_work); > pm_runtime_disable(&pdev->dev); > + cpu_latency_qos_remove_request(&priv->pm_qos_request); > return ret; Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> An unrelated comment to the patch itself, there seems to be somewhat handwavy and possibly wrong calculation for the pm qos latency. First of all, I think it would want something based on port->frame_time, and I'm far from convinced that 64 is right as it matches FIFO size which doesn't feel correct for a wakeup related time.
* Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> [230508 09:55]: > An unrelated comment to the patch itself, there seems to be somewhat > handwavy and possibly wrong calculation for the pm qos latency. First of > all, I think it would want something based on port->frame_time, and I'm > far from convinced that 64 is right as it matches FIFO size which doesn't > feel correct for a wakeup related time. Thanks for spotting it, good point. I'll take a look at that in a separate patch. Regards, Tony
diff --git a/drivers/tty/serial/8250/8250_omap.c b/drivers/tty/serial/8250/8250_omap.c --- a/drivers/tty/serial/8250/8250_omap.c +++ b/drivers/tty/serial/8250/8250_omap.c @@ -1532,7 +1532,9 @@ static int omap8250_probe(struct platform_device *pdev) err: pm_runtime_dont_use_autosuspend(&pdev->dev); pm_runtime_put_sync(&pdev->dev); + flush_work(&priv->qos_work); pm_runtime_disable(&pdev->dev); + cpu_latency_qos_remove_request(&priv->pm_qos_request); return ret; }
If serial8250_register_8250_port() fails, the SoC can hang as the deferred PMQoS work will still run as is not flushed and removed. Fixes: 61929cf0169d ("tty: serial: Add 8250-core based omap driver") Signed-off-by: Tony Lindgren <tony@atomide.com> --- drivers/tty/serial/8250/8250_omap.c | 2 ++ 1 file changed, 2 insertions(+)