On Tue, Mar 11, 2014 at 1:10 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: > On Tue, Mar 11, 2014 at 12:10:02AM +0100, Andreas Noever wrote: >> On Mon, Mar 10, 2014 at 9:43 PM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: >> > On Sat, Mar 8, 2014 at 2:55 AM, Andreas Noever <andreas.noever@xxxxxxxxx> wrote: >> >> On Sat, Mar 8, 2014 at 2:04 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote: >> > >> >>> If we did that, INTX_DISABLE would be cleared by the first >> >>> pci_enable_device() and pci_reenable_device() wouldn't do anything, >> >>> leaving it cleared. The resulting state (cleared) would be the same, >> >>> but the transitions would be gone, and maybe those are important. >> >> Just a quick note: With pci_intx_for_msi removed no hotplug events are >> >> ever delivered. Everything else still works though. So it is either a >> >> problem specific to Thunderbolt bridges or maybe it just affects >> >> hotplug (and PME?) interrupts. >> > >> > Interesting. This is on a MacBook, isn't it? If you have Mac OS on >> > it, is there a way you can do the equivalent of lspci on it? I'm >> > curious about whether it sets INTx_DISABLE when it enables MSI. >> >> lspci -vv and lspci -vv -xxxx attached (yes, someone made a port). >> >> It looks like Mac OS sets DisINTx for all devices that have MSI >> enabled. The only exception is the Thunderbolt controller (no >> idea...). But the hotplug bridges all have DisINTx+. > > OK, thanks. I don't know what to make of that. > > Here's a possible patch; can you try it out? > > > PCI: Do not enable INTx in pci_reenable_device() > > From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > > Previously we cleared the Interrupt Disable bit in do_pci_enable_device(), > which is used by both pci_enable_device() and pci_reenable_device(). But > we use pci_reenable_device() after the driver may have enabled MSI or > MSI-X, and we *set* Interrupt Disable as part of enabling MSI/MSI-X. > > The pciehp hot-plug path uses pci_reenable_device() on the hotplug bridge, > and clearing its Interrupt Disable bit makes its hotplug event-reporting > MSI stop working. > > Fixes: 1f42db786b14 PCI: Enable INTx if BIOS left them disabled > Link: https://bugzilla.kernel.org/show_bug.cgi?id=71691 > Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> > --- > drivers/pci/pci.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 8dc3e701ec57..79fc89c6c3f3 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -1192,6 +1192,9 @@ static int do_pci_enable_device(struct pci_dev *dev, int bars) > return err; > pci_fixup_device(pci_fixup_enable, dev); > > + if (dev->msi_enabled || dev->msix_enabled) > + return 0; > + > pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin); > if (pin) { > pci_read_config_word(dev, PCI_COMMAND, &cmd); That fixes it. Thanks, Andreas -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
