From 8011b508cf0ddbdbda03820f4fa6cd484a6d9aed Mon Sep 17 00:00:00 2001 From: Matthew Rosato Date: Fri, 10 Nov 2023 12:51:08 -0500 Subject: [PATCH] s390x/pci: only limit DMA aperture if vfio DMA limit reported If the host kernel lacks vfio DMA limit reporting, do not attempt to shrink the guest DMA aperture. Fixes: df202e3ff3 ("s390x/pci: shrink DMA aperture to be bound by vfio DMA limit") Signed-off-by: Matthew Rosato Message-ID: <20231110175108.465851-3-mjrosato@linux.ibm.com> Signed-off-by: Thomas Huth --- hw/s390x/s390-pci-vfio.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/s390x/s390-pci-vfio.c b/hw/s390x/s390-pci-vfio.c index e28573b593..7dbbc76823 100644 --- a/hw/s390x/s390-pci-vfio.c +++ b/hw/s390x/s390-pci-vfio.c @@ -136,7 +136,7 @@ static void s390_pci_read_base(S390PCIBusDevice *pbdev, * to the guest based upon the vfio DMA limit. */ vfio_size = pbdev->iommu->max_dma_limit << TARGET_PAGE_BITS; - if (vfio_size < (cap->end_dma - cap->start_dma + 1)) { + if (vfio_size > 0 && vfio_size < cap->end_dma - cap->start_dma + 1) { pbdev->zpci_fn.edma = cap->start_dma + vfio_size - 1; } } -- 2.11.4.GIT