--- XFree86-4.1.0/xc/programs/Xserver/hw/xfree86/drivers/mga/mga_dri.c.orig	Wed May  2 17:06:09 2001
+++ XFree86-4.1.0/xc/programs/Xserver/hw/xfree86/drivers/mga/mga_dri.c	Sun Jun 17 23:03:55 2001
@@ -897,6 +897,7 @@
    DRIInfoPtr pDRIInfo;
    MGADRIPtr pMGADRI;
    MGADRIServerPrivatePtr pMGADRIServer;
+   CARD32 pciCommand;
 
    switch ( pMga->Chipset ) {
    case PCI_CHIP_MGAG400:
@@ -1118,6 +1119,11 @@
       return FALSE;
    }
    xf86DrvMsg( pScrn->scrnIndex, X_INFO, "[dri] visual configs initialized\n" );
+
+   /* Enable bus mastering in PCI config space */
+   pciCommand = pciReadLong(pMga->PciTag, PCI_CMD_STAT_REG);
+   pciWriteLong(pMga->PciTag, PCI_CMD_STAT_REG,
+		pciCommand | PCI_CMD_MASTER_ENABLE);
 
    return TRUE;
 }