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| author | Eric Auger <eric.auger@redhat.com> | 2023-09-27 16:05:44 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-11-08 17:26:36 +0100 |
| commit | 3a6cee2bfb53833fb7c3ec68ca01f51fce784384 (patch) | |
| tree | 8bacf36ee87b34b4c87ec2528f38ca400699c63d | |
| parent | fbc9a8718f3136c3354bf0055eb1ec696178eea1 (diff) | |
| download | aa-3a6cee2bfb53833fb7c3ec68ca01f51fce784384.tar.gz | |
vhost: Allow null msg.size on VHOST_IOTLB_INVALIDATE
commit ca50ec377c2e94b0a9f8735de2856cd0f13beab4 upstream.
Commit e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb
entries") Forbade vhost iotlb msg with null size to prevent entries
with size = start = 0 and last = ULONG_MAX to end up in the iotlb.
Then commit 95932ab2ea07 ("vhost: allow batching hint without size")
only applied the check for VHOST_IOTLB_UPDATE and VHOST_IOTLB_INVALIDATE
message types to fix a regression observed with batching hit.
Still, the introduction of that check introduced a regression for
some users attempting to invalidate the whole ULONG_MAX range by
setting the size to 0. This is the case with qemu/smmuv3/vhost
integration which does not work anymore. It Looks safe to partially
revert the original commit and allow VHOST_IOTLB_INVALIDATE messages
with null size. vhost_iotlb_del_range() will compute a correct end
iova. Same for vhost_vdpa_iotlb_unmap().
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Fixes: e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb entries")
Cc: stable@vger.kernel.org # v5.17+
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20230927140544.205088-1-eric.auger@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/vhost/vhost.c | 4 |
1 files changed, 1 insertions, 3 deletions
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 047fa2faef5661..bc14f1245a651d 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1171,9 +1171,7 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, goto done; } - if ((msg.type == VHOST_IOTLB_UPDATE || - msg.type == VHOST_IOTLB_INVALIDATE) && - msg.size == 0) { + if (msg.type == VHOST_IOTLB_UPDATE && msg.size == 0) { ret = -EINVAL; goto done; } |