I think that if a PCI bus is a root bus, attached to a host bridge not a

PCI->PCI bridge, then bus->self is allowed to be NULL. Certainly that's
the case on my Pegasos, and it makes the MGA DRM driver oops...

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Dave Airlie <airlied@linux.ie>

diff --git a/drivers/char/drm/mga_drv.c b/drivers/char/drm/mga_drv.c
index 0cc7c30..1713451 100644 (file)
--- a/drivers/char/drm/mga_drv.c
+++ b/drivers/char/drm/mga_drv.c
@@ -161,7 +161,7 @@ static int mga_driver_device_is_agp(drm_device_t * dev)
         * device.
         */
 
-       if ((pdev->device == 0x0525)
+       if ((pdev->device == 0x0525) && pdev->bus->self
            && (pdev->bus->self->vendor == 0x3388)
            && (pdev->bus->self->device == 0x0021)) {
                return 0;