4.4-stable review patch. If anyone has any objections, please let me know.
------------------ From: Joerg Roedel <[email protected]> commit b548e786ce47017107765bbeb0f100202525ea83 upstream. The default domain for a device might also be identity-mapped. In this case the kernel would crash when unity mappings are defined for the device. Fix that by making sure the domain is a dma_ops domain. Fixes: 0bb6e243d7fb ('iommu/amd: Support IOMMU_DOMAIN_DMA type allocation') Signed-off-by: Joerg Roedel <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/iommu/amd_iommu.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -352,9 +352,11 @@ static void init_iommu_group(struct devi if (!domain) goto out; - dma_domain = to_pdomain(domain)->priv; + if (to_pdomain(domain)->flags == PD_DMA_OPS_MASK) { + dma_domain = to_pdomain(domain)->priv; + init_unity_mappings_for_device(dev, dma_domain); + } - init_unity_mappings_for_device(dev, dma_domain); out: iommu_group_put(group); }
