[PATCH v4 3/3] vhost/vsock: keep IOTLB across feature updates
Jia Jia <[email protected]>
| Newsgroups | org.kernel.vger.kvm,dev.linux.lists.virtualization,org.kernel.vger.linux-kernel,org.kernel.vger.netdev |
|---|---|
| Message-ID | <[email protected]> |
VHOST_SET_FEATURES is also used to update logging while a device is
running. When ACCESS_PLATFORM stays enabled, allocating a new empty
IOTLB on every call drops valid translations and forces avoidable
misses.
Initialize the device IOTLB only when one does not already exist.
Fixes: e13a6915a03f ("vhost/vsock: add IOTLB API support")
Signed-off-by: Jia Jia <[email protected]>
---
drivers/vhost/vsock.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/vhost/vsock.c b/drivers/vhost/vsock.c
index b69c260eaeff..9142fa1143b2 100644
--- a/drivers/vhost/vsock.c
+++ b/drivers/vhost/vsock.c
@@ -869,6 +869,7 @@ static int vhost_vsock_set_features(struct vhost_vsock *vsock, u64 features)
vsock->dev.iotlb)
vhost_clear_device_iotlb(&vsock->dev);
- if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM))) {
+ if ((features & (1ULL << VIRTIO_F_ACCESS_PLATFORM)) &&
+ !vsock->dev.iotlb) {
if (vhost_init_device_iotlb(&vsock->dev))
goto err;
--
2.34.1