diff options
| author | Alex Bennée <alex.bennee@linaro.org> | 2021-02-25 14:12:17 +0000 |
|---|---|---|
| committer | Sergio Lopez <slp@sinrega.org> | 2021-06-17 15:19:00 +0200 |
| commit | 2e4396c9ccd38afa05078826e41857ed03559b23 (patch) | |
| tree | 618d21b875530e427ff9e7fd9416e63dd1f1aedb | |
| parent | e294ed66fcc12e033957f20034ae5fef5bb9eeac (diff) | |
| download | vmm_vhost-2e4396c9ccd38afa05078826e41857ed03559b23.tar.gz | |
slave_req_handler: relax reply_ack_flag test
In reality the real guest may never see the
VHOST_USER_F_PROTOCOL_FEATURES bit during the device feature
negotiation. It is explicitly marked as UNUSED in the VirtIO spec so
the it would be perfectly valid for it to be ignored by the virtio
driver. The vhost-user spec explicitly states about the GET/SET
PROTOCOL FEATURES messages:
Slave that reported ``VHOST_USER_F_PROTOCOL_FEATURES`` must
support this message even before ``VHOST_USER_SET_FEATURES`` was
called.
which implies the final acked feature set shouldn't impact on the
negotiated VHOST_USER_PROTOCOL_F_REPLY_ACK feature. This prevents a
hang with the QEMU remote end which makes it's determination to ask
for a reply based only on the negotiated protocol feature set:
virtio_has_feature(dev->protocol_features,
VHOST_USER_PROTOCOL_F_REPLY_ACK);
Let's be liberal in what we accept.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Michael S. Tsirkin <mst@redhat.com>
| -rw-r--r-- | src/vhost_user/slave_req_handler.rs | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/src/vhost_user/slave_req_handler.rs b/src/vhost_user/slave_req_handler.rs index f2130b7..f899bd6 100644 --- a/src/vhost_user/slave_req_handler.rs +++ b/src/vhost_user/slave_req_handler.rs @@ -777,7 +777,6 @@ impl<S: VhostUserSlaveReqHandler> SlaveReqHandler<S> { let vflag = VhostUserVirtioFeatures::PROTOCOL_FEATURES.bits(); let pflag = VhostUserProtocolFeatures::REPLY_ACK; if (self.virtio_features & vflag) != 0 - && (self.acked_virtio_features & vflag) != 0 && self.protocol_features.contains(pflag) && (self.acked_protocol_features & pflag.bits()) != 0 { |