On 1/27/21 8:19 AM, Stefan Hajnoczi wrote:
On Tue, Jan 26, 2021 at 03:23:38PM -0300, lagar...@linux.ibm.com wrote:
From: Leonardo Garcia <lagar...@br.ibm.com>
Currently, as IOMMU and ATS are not supported, if a user mistakenly set
any of them and tries to mount the vhost-user filesystem inside the
guest, whenever the user tries to access the mount point, the system
will hang forever.
Signed-off-by: Leonardo Garcia <lagar...@br.ibm.com>
---
hw/virtio/vhost-user-fs-pci.c | 7 +++++++
hw/virtio/vhost-user-fs.c | 5 +++++
2 files changed, 12 insertions(+)
diff --git a/hw/virtio/vhost-user-fs-pci.c b/hw/virtio/vhost-user-fs-pci.c
index 2ed8492b3f..564d1fd108 100644
--- a/hw/virtio/vhost-user-fs-pci.c
+++ b/hw/virtio/vhost-user-fs-pci.c
@@ -11,6 +11,8 @@
* top-level directory.
*/
+#include "qemu/osdep.h"
+#include "qapi/error.h"
#include "qemu/osdep.h"
#include "hw/qdev-properties.h"
#include "hw/virtio/vhost-user-fs.h"
@@ -45,6 +47,11 @@ static void vhost_user_fs_pci_realize(VirtIOPCIProxy
*vpci_dev, Error **errp)
vpci_dev->nvectors = dev->vdev.conf.num_request_queues + 2;
}
+ if (vpci_dev->flags & VIRTIO_PCI_FLAG_ATS) {
+ error_setg(errp, "ATS is currently not supported with
vhost-user-fs-pci");
+ return;
+ }
Why is this check needed in addition to VIRTIO_F_IOMMU_PLATFORM?
What needs to be added to support ATS?
As I am working on v2 for this patch, I revisited this. There is no need
for this check. ATS works fine. The only problem is with the
iommu_platform flag.
Cheers,
Leo
+
qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
}
diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
index ac4fc34b36..914d68b3ee 100644
--- a/hw/virtio/vhost-user-fs.c
+++ b/hw/virtio/vhost-user-fs.c
@@ -203,6 +203,11 @@ static void vuf_device_realize(DeviceState *dev, Error
**errp)
return;
}
+ if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) {
+ error_setg(errp, "IOMMU is currently not supported with
vhost-user-fs");
+ return;
+ }
+
if (!vhost_user_init(&fs->vhost_user, &fs->conf.chardev, errp)) {
I thought IOMMU support depends on the vhost-user device backend (e.g.
virtiofsd), so the vhost-user backend should participate in advertising
this feature.
Perhaps the check should be:
ret = vhost_dev_init(&fs->vhost_dev, &fs->vhost_user,
VHOST_BACKEND_TYPE_USER, 0);
if (ret < 0) {
error_setg_errno(errp, -ret, "vhost_dev_init failed");
goto err_virtio;
}
+
+ if (virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM) &&
+ !(fs->vhost_dev.hdev_features & (1ull << VIRTIO_F_IOMMU_PLATFORM))) {
+ error_setg(errp, "IOMMU is not supported by the vhost-user device
backend");
+ goto err_iommu_needed;
+ }
Also, can this logic be made generic for all vhost-user devices? It's
not really specific to vhost-user-fs.
Stefan
