Upstream commit 7d6e1329652e ("vfio iommu: Add dma available capability") should probably have been identified as a stable candidate originally, as without this available in a KVM host QEMU guests on at least s390x can end up with broken PCI passthrough devices, as the guest is unaware of the vfio DMA limit and can easily overrun it. The commit in question won't fit cleanly to 5.4, so I've included a proposed backport patch. Matthew Rosato (1): vfio iommu: Add dma available capability drivers/vfio/vfio_iommu_type1.c | 22 ++++++++++++++++++++++ include/uapi/linux/vfio.h | 15 +++++++++++++++ 2 files changed, 37 insertions(+) -- 1.8.3.1