@@ -819,12 +819,19 @@ static int vfio_dma_map(VFIOContainer *container, target_phys_addr_t iova,
map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
}
- if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map)) {
- DPRINTF("VFIO_MAP_DMA: %d\n", -errno);
- return -errno;
+ /*
+ * Try the mapping, if it fails with EBUSY, unmap the region and try
+ * again. This shouldn't be necessary, but we sometimes see it in
+ * the the VGA ROM space.
+ */
+ if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0 ||
+ (errno == EBUSY && vfio_dma_unmap(container, iova, size) == 0 &&
+ ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map) == 0)) {
+ return 0;
}
- return 0;
+ DPRINTF("VFIO_MAP_DMA: %d\n", -errno);
+ return -errno;
}
static void vfio_listener_dummy1(MemoryListener *listener)
Occasionally we get regions added that overlap with existing mappings. These always seems to be in the VGA ROM range. VFIO returns EBUSY for these mapping attempts. We can try a little harder and assume that the latest mapping is correct by removing any overlapping ranges and retrying the original request. Signed-off-by: Alex Williamson <alex.williamson@redhat.com> --- hw/vfio_pci.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-)