[PATCH] ARM: imx6: Fix "BUG: scheduling while atomic" if PCIe switch is attached

[Lucas Stach]

Am Montag, den 22.06.2015, 10:30 -0300 schrieb Fabio Estevam:
> On Thu, Jun 18, 2015 at 5:27 AM, Lucas Stach <l.stach at pengutronix.de> wrote:
> 
> >> diff --git a/drivers/pci/host/pci-imx6.c b/drivers/pci/host/pci-imx6.c
> >> index fdb9536..c63691c 100644
> >> --- a/drivers/pci/host/pci-imx6.c
> >> +++ b/drivers/pci/host/pci-imx6.c
> >> @@ -489,7 +489,7 @@ static int imx6_pcie_link_up(struct pcie_port *pp)
> >>                * Wait a little bit, then re-check if the link finished
> >>                * the training.
> >>                */
> >> -             usleep_range(1000, 2000);
> >> +             mdelay(20);
> >
> > While switching to mdelay might be the right thing to do here, you are
> > also changing the timeout. This is a change in behavior and so not okay.
> 
> msleep(2) is not recommended according to Documentation/timers/timers-howto.txt.
> 
> What would be the proper fix then?
> 
mdelay(2) is completely reasonable. Note the difference between delay
and sleep.

The mid-term correct solution would be to move all the link-up handling
out of the atomic path.

Regards,
Lucas
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