From: Michal Privoznik <mprivozn@redhat.com> Just like with other features, check whether QEMU supports them based on capabilities. Now, instead of inventing a new QEMU capability, an existing one can be used: QEMU_CAPS_VIRTIO_IOMMU_AW_BITS. This is because the aw-bits and granule attributes were introduced into QEMU in close succession (v9.0.0-rc0~9^2~7 v9.0.0-rc0~9^2~11), neither can be disabled at compile time and backporting just one without the other makes almost no sense. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- src/qemu/qemu_validate.c | 30 +++++++++++++++++++++--------- 1 file changed, 21 insertions(+), 9 deletions(-) diff --git a/src/qemu/qemu_validate.c b/src/qemu/qemu_validate.c index 8f85334cf9..6b44d8d785 100644 --- a/src/qemu/qemu_validate.c +++ b/src/qemu/qemu_validate.c @@ -5685,15 +5685,27 @@ qemuValidateDomainDeviceDefIOMMU(const virDomainIOMMUDef *iommu, return -1; } - /* QEMU supports only 4KiB, 8KiB, 16KiB and 64KiB granule size */ - if (iommu->granule > 0 && - !(iommu->granule == 4 || - iommu->granule == 8 || - iommu->granule == 16 || - iommu->granule == 64)) { - virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", - _("iommu: unsupported granule size. Supported values are 4, 8, 16 and 64 KiB")); - return -1; + if (iommu->granule > 0) { + /* QEMU supports only 4KiB, 8KiB, 16KiB and 64KiB granule size */ + if (!(iommu->granule == 4 || + iommu->granule == 8 || + iommu->granule == 16 || + iommu->granule == 64)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("iommu: unsupported granule size. Supported values are 4, 8, 16 and 64 KiB")); + return -1; + } + + /* While the QEMU_CAPS_VIRTIO_IOMMU_AW_BITS tracks .aw-bits attribute of + * virtio-iommu it is also a good indicator of .granule attribute as both + * attributes were introduced in neighboring commits, in the same release, + * neither can be disabled at compile time and backporting one without the + * other makes no sense. */ + if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_IOMMU_AW_BITS)) { + virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("iommu: page granule is not supported with this QEMU binary")); + return -1; + } } return 0; -- 2.52.0