Thread (3 messages) 3 messages, 3 authors, 2022-06-23

Re: [PATCH] vhost-vdpa: call vhost_vdpa_cleanup during the release

From: Eugenio Perez Martin <eperezma@redhat.com>
Date: 2022-06-22 18:54:03
Also in: kvm, lkml

On Wed, Jun 22, 2022 at 5:14 PM Stefano Garzarella [off-list ref] wrote:
Before commit 3d5698793897 ("vhost-vdpa: introduce asid based IOTLB")
we call vhost_vdpa_iotlb_free() during the release to clean all regions
mapped in the iotlb.

That commit removed vhost_vdpa_iotlb_free() and added vhost_vdpa_cleanup()
to do some cleanup, including deleting all mappings, but we forgot to call
it in vhost_vdpa_release().

This causes that if an application does not remove all mappings explicitly
(or it crashes), the mappings remain in the iotlb and subsequent
applications may fail if they map the same addresses.
I tested this behavior even by sending SIGKILL to qemu. The failed map
is reproducible easily before applying this patch and applying it
fixes the issue properly.
Calling vhost_vdpa_cleanup() also fixes a memory leak since we are not
freeing `v->vdev.vqs` during the release from the same commit.

Since vhost_vdpa_cleanup() calls vhost_dev_cleanup() we can remove its
call from vhost_vdpa_release().
Tested-by: Eugenio Pérez <eperezma@redhat.com>
quoted hunk ↗ jump to hunk
Fixes: 3d5698793897 ("vhost-vdpa: introduce asid based IOTLB")
Cc: gautam.dawar@xilinx.com
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
---
 drivers/vhost/vdpa.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 5ad2596c6e8a..23dcbfdfa13b 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -1209,7 +1209,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep)
        vhost_dev_stop(&v->vdev);
        vhost_vdpa_free_domain(v);
        vhost_vdpa_config_put(v);
-       vhost_dev_cleanup(&v->vdev);
+       vhost_vdpa_cleanup(v);
        mutex_unlock(&d->mutex);

        atomic_dec(&v->opened);
--
2.36.1
  
Keyboard shortcuts
hback out one level
jnext message in thread
kprevious message in thread
ldrill in
Escclose help / fold thread tree
?toggle this help