diff options
author | Eric Auger <eric.auger@redhat.com> | 2023-09-27 17:05:44 +0300 |
---|---|---|
committer | Michael S. Tsirkin <mst@redhat.com> | 2023-10-18 18:29:56 +0300 |
commit | ca50ec377c2e94b0a9f8735de2856cd0f13beab4 (patch) | |
tree | 660f91c1ff5983868a8e9b03244b862f8b6b29f7 /drivers/vhost | |
parent | abb0dcf9938c93f765abf8cb45567cadef0af6b2 (diff) | |
download | linux-ca50ec377c2e94b0a9f8735de2856cd0f13beab4.tar.xz |
vhost: Allow null msg.size on VHOST_IOTLB_INVALIDATE
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>
Diffstat (limited to 'drivers/vhost')
-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 c71d573f1c94..e0c181ad17e3 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1458,9 +1458,7 @@ 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; } |