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From: David Woodhouse <dwmw2@infradead.org>
To: airlied@linux.ie, greg@kroah.com
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Date: Sat, 19 Nov 2005 23:19:49 +0000
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Cc: linuxppc-dev@ozlabs.org
Subject: [PATCH] Fix oops in MGA DRM on root bus.
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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>

diff --git a/drivers/char/drm/mga_drv.c b/drivers/char/drm/mga_drv.c
--- 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.
 	 */
 
-	if ((pdev->device == 0x0525)
+	if ((pdev->device == 0x0525) && pdev->bus->self &&
 	    && (pdev->bus->self->vendor == 0x3388)
 	    && (pdev->bus->self->device == 0x0021)) {
 		return 0;

-- 
dwmw2