Since 3461a068661c we don't automatically do a pcie_wait_cmd() for as part of pcie_write_cmd(), it needs to be called explicitly or triggered by the next pcie_write_cmd(). However, when we do a secondary bus reset and we're using pcie_write_cmd() to make sure that we don't see that bus reset as a hotplug event, we really want to make sure the update is complete. Testing on an old Lenovo S20 system, which sets surprise hotplug for some slots, this failure to flush results in a link down event seen by the hotplug controller when we issue the bus reset and returns us to the undesireable behavior of removing and re-adding the device. Force a flush by adding an explicit call to pcie_wait_cmd(). Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx [3.17] --- drivers/pci/hotplug/pciehp_hpc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 0ebf754..e540966 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -660,6 +660,7 @@ int pciehp_reset_slot(struct slot *slot, int probe) pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0); if (pciehp_poll_mode) del_timer_sync(&ctrl->poll_timer); + pcie_wait_cmd(ctrl); pci_reset_bridge_secondary_bus(ctrl->pcie->port); -- 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
