On 09/12/2017 02:04 PM, Johannes Berg wrote:
> On Tue, 2017-09-12 at 13:43 -0600, Jens Axboe wrote:
>
>> CC'ing the guilty part and Bjorn. I'm assuming it's the
>> pci_is_enabled() check, since the rest of the patch shouldn't have
>> functional changes.
>
> and pci_enable_bridge() already checks if it's already enabled, but
> still enables mastering in that case if it isn't:
>
> static void pci_enable_bridge(struct pci_dev *dev)
> {
> [...]
> if (pci_is_enabled(dev)) {
> if (!dev->is_busmaster)
> pci_set_master(dev);
> return;
> }
>
> so I guess due to the new check we end up with mastering disabled, and
> thus the firmware can't load since that's a DMA thing?
Bjorn/Srinath, any input here? This is a regression that prevents wifi
from working on a pretty standard laptop. It'd suck to have this be in
-rc1. Seems like the trivial fix would be:
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index b0002daa50f3..ffbe11dbdd61 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1394,7 +1394,7 @@ static int pci_enable_device_flags(struct pci_dev *dev,
unsigned long flags)
return 0; /* already enabled */
bridge = pci_upstream_bridge(dev);
- if (bridge && !pci_is_enabled(bridge))
+ if (bridge)
pci_enable_bridge(bridge);
/* only skip sriov related */
--
Jens Axboe
