summary refs log tree commit diff stats
path: root/hw/vfio/common.c
diff options
context:
space:
mode:
authorJean-Philippe Brucker <jean-philippe@linaro.org>2020-10-30 19:05:10 +0100
committerMichael S. Tsirkin <mst@redhat.com>2020-11-03 16:39:05 -0500
commit1b296c3def4b9b63d2fdbce6646edd108a3e616c (patch)
tree4641ac050f0430c0018bac7c1e1d6998d57f6cc3 /hw/vfio/common.c
parent5c3cfe33f4185841feaedd07bea1d6d7e02011a0 (diff)
downloadfocaccia-qemu-1b296c3def4b9b63d2fdbce6646edd108a3e616c.tar.gz
focaccia-qemu-1b296c3def4b9b63d2fdbce6646edd108a3e616c.zip
vfio: Don't issue full 2^64 unmap
IOMMUs may declare memory regions spanning from 0 to UINT64_MAX. When
attempting to deal with such region, vfio_listener_region_del() passes a
size of 2^64 to int128_get64() which throws an assertion failure.  Even
ignoring this, the VFIO_IOMMU_DMA_MAP ioctl cannot handle this size
since the size field is 64-bit. Split the request in two.

Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Message-Id: <20201030180510.747225-11-jean-philippe@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/vfio/common.c')
-rw-r--r--hw/vfio/common.c11
1 files changed, 11 insertions, 0 deletions
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 35895b18a6..c1fdbf17f2 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -950,6 +950,17 @@ static void vfio_listener_region_del(MemoryListener *listener,
     }
 
     if (try_unmap) {
+        if (int128_eq(llsize, int128_2_64())) {
+            /* The unmap ioctl doesn't accept a full 64-bit span. */
+            llsize = int128_rshift(llsize, 1);
+            ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
+            if (ret) {
+                error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "
+                             "0x%"HWADDR_PRIx") = %d (%m)",
+                             container, iova, int128_get64(llsize), ret);
+            }
+            iova += int128_get64(llsize);
+        }
         ret = vfio_dma_unmap(container, iova, int128_get64(llsize), NULL);
         if (ret) {
             error_report("vfio_dma_unmap(%p, 0x%"HWADDR_PRIx", "