• Dave Airlie's avatar
    drm: move pci bus master enable into driver. · 466e69b8
    Dave Airlie authored
    The current enabling of bus mastering in the drm midlayer allows a large
    race condition under kexec. When a kexec'ed kernel re-enables bus mastering
    for the GPU, previously setup dma blocks may cause writes to random pieces
    of memory. On radeon the writeback mechanism can cause these sorts of issues.
    
    This patch doesn't fix the problem, but it moves the bus master enable under
    the individual drivers control so they can move enabling it until later in
    their load cycle and close the race.
    
    Fix for radeon kms driver will be in a follow-up patch.
    Signed-off-by: default avatarDave Airlie <airlied@redhat.com>
    466e69b8
radeon_kms.c 15.4 KB