[PATCH 3.13 126/212] PCI: shpchp: Check bridge's secondary (not primary) bus speed

Kamal Mostafa
2014-06-17T21:43:40Z

From: Marcel Apfelbaum <marcel.a@redhat.com>

commit 93fa9d32670f5592c8e56abc9928fc194e1e72fc upstream.

When a new device is added below a hotplug bridge, the bridge's secondary
bus speed and the device's bus speed must match. The shpchp driver
previously checked the bridge's *primary* bus speed, not the secondary bus
speed.

This caused hot-add errors like:

shpchp 0000:00:03.0: Speed of bus ff and adapter 0 mismatch

Check the secondary bus speed instead.

[bhelgaas: changelog]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=75251
Fixes: 3749c51ac6c1 ("PCI: Make current and maximum bus speeds part of the PCI core")
Signed-off-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
---
drivers/pci/hotplug/shpchp_ctrl.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/shpchp_ctrl.c b/drivers/pci/hotplug/shpchp_ctrl.c
index 5849927..6efc2ec 100644
--- a/drivers/pci/hotplug/shpchp_ctrl.c
+++ b/drivers/pci/hotplug/shpchp_ctrl.c
@@ -282,8 +282,8 @@ static int board_added(struct slot *p_slot)
return WRONG_BUS_FREQUENCY;
}

- bsp = ctrl->pci_dev->bus->cur_bus_speed;
- msp = ctrl->pci_dev->bus->max_bus_speed;
+ bsp = ctrl->pci_dev->subordinate->cur_bus_speed;
+ msp = ctrl->pci_dev->subordinate->max_bus_speed;

/* Check if there are other slots or devices on the same bus */
if (!list_empty(&ctrl->pci_dev->subordinate->devices))
--
1.9.1