sys/vm/device_pager.c old_dev_pager_fault() dev_dmmap needs offset << PAGE_SHIFT
Date: Mon Jul 29 22:39:56 2013 +0200
kernel: Port new device_pager interface from FreeBSD
should probably be amended in sys/vm/device_pager.c, function old_dev_pager_fault() to use
paddr = pmap_phys_address(
dev_dmmap(dev, offset << PAGE_SHIFT, prot));
similar to what had been used in the previous version of dev_pager_getpage().
Without this change, legacy drm systems running say a Radeon 4xxx graphics card failed to have dports Xorg start.