From 94df5b2180d61fb2ee2b04cc007981e58b6479a9 Mon Sep 17 00:00:00 2001 From: Eric Auger Date: Wed, 5 Jul 2023 18:51:17 +0200 Subject: virtio-iommu: Fix 64kB host page size VFIO device assignment When running on a 64kB page size host and protecting a VFIO device with the virtio-iommu, qemu crashes with this kind of message: qemu-kvm: virtio-iommu page mask 0xfffffffffffff000 is incompatible with mask 0x20010000 qemu: hardware error: vfio: DMA mapping failed, unable to continue This is due to the fact the IOMMU MR corresponding to the VFIO device is enabled very late on domain attach, after the machine init. The device reports a minimal 64kB page size but it is too late to be applied. virtio_iommu_set_page_size_mask() fails and this causes vfio_listener_region_add() to end up with hw_error(); To work around this issue, we transiently enable the IOMMU MR on machine init to collect the page size requirements and then restore the bypass state. Fixes: 90519b9053 ("virtio-iommu: Add bypass mode support to assigned device") Signed-off-by: Eric Auger Message-Id: <20230705165118.28194-2-eric.auger@redhat.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin Reviewed-by: Jean-Philippe Brucker Tested-by: Jean-Philippe Brucker Reviewed-by: Zhenzhong Duan --- include/hw/virtio/virtio-iommu.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h index 2ad5ee320b..a93fc5383e 100644 --- a/include/hw/virtio/virtio-iommu.h +++ b/include/hw/virtio/virtio-iommu.h @@ -61,6 +61,8 @@ struct VirtIOIOMMU { QemuRecMutex mutex; GTree *endpoints; bool boot_bypass; + Notifier machine_done; + bool granule_frozen; }; #endif -- cgit v1.2.3