Stefano Garzarella 4daa5054c5 vhost: enable vrings in vhost_dev_start() for vhost-user devices ... Commit 02b61f38d3 ("hw/virtio: incorporate backend features in features") properly negotiates VHOST_USER_F_PROTOCOL_FEATURES with the vhost-user backend, but we forgot to enable vrings as specified in docs/interop/vhost-user.rst: If ``VHOST_USER_F_PROTOCOL_FEATURES`` has not been negotiated, the ring starts directly in the enabled state. If ``VHOST_USER_F_PROTOCOL_FEATURES`` has been negotiated, the ring is initialized in a disabled state and is enabled by ``VHOST_USER_SET_VRING_ENABLE`` with parameter 1. Some vhost-user front-ends already did this by calling vhost_ops.vhost_set_vring_enable() directly: - backends/cryptodev-vhost.c - hw/net/virtio-net.c - hw/virtio/vhost-user-gpio.c But most didn't do that, so we would leave the vrings disabled and some backends would not work. We observed this issue with the rust version of virtiofsd [1], which uses the event loop [2] provided by the vhost-user-backend crate where requests are not processed if vring is not enabled. Let's fix this issue by enabling the vrings in vhost_dev_start() for vhost-user front-ends that don't already do this directly. Same thing also in vhost_dev_stop() where we disable vrings. [1] https://gitlab.com/virtio-fs/virtiofsd [2] https://github.com/rust-vmm/vhost/blob/240fc2966/crates/vhost-user-backend/src/event_loop.rs#L217 Fixes: 02b61f38d3 ("hw/virtio: incorporate backend features in features") Reported-by: German Maglione <gmaglione@redhat.com> Tested-by: German Maglione <gmaglione@redhat.com> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com> Acked-by: Raphael Norwitz <raphael.norwitz@nutanix.com> Message-Id: <20221123131630.52020-1-sgarzare@redhat.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Michael S. Tsirkin <mst@redhat.com> Message-Id: <20221130112439.2527228-3-alex.bennee@linaro.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>		2022-12-01 02:30:04 -05:00
..
tpm	tpm_emulator: Have swtpm relock storage upon migration fall-back	2022-09-13 10:27:17 -04:00
confidential-guest-support.c
cryptodev-builtin.c	virtio-crypto: Support asynchronous mode	2022-11-02 06:56:32 -04:00
cryptodev-lkcf.c	cryptodev: Add a lkcf-backend for cryptodev	2022-11-02 06:56:32 -04:00
cryptodev-vhost-user.c	virtio-crypto: Support asynchronous mode	2022-11-02 06:56:32 -04:00
cryptodev-vhost.c	vhost: enable vrings in vhost_dev_start() for vhost-user devices	2022-12-01 02:30:04 -05:00
cryptodev.c	virtio-crypto: Support asynchronous mode	2022-11-02 06:56:32 -04:00
dbus-vmstate1.xml
dbus-vmstate.c
hostmem-epc.c
hostmem-file.c
hostmem-memfd.c
hostmem-ram.c
hostmem.c	hostmem: Allow for specifying a ThreadContext for preallocation	2022-10-27 11:01:03 +02:00
Kconfig
meson.build	cryptodev: Add a lkcf-backend for cryptodev	2022-11-02 06:56:32 -04:00
rng-builtin.c
rng-egd.c	backends: Improve error messages when property can no longer be set	2022-10-27 07:56:56 +02:00
rng-random.c	backends: Improve error messages when property can no longer be set	2022-10-27 07:56:56 +02:00
rng.c
trace-events
trace.h
vhost-user.c	vhost: enable vrings in vhost_dev_start() for vhost-user devices	2022-12-01 02:30:04 -05:00