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); -- 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
