The current handling of invalid virtqueue elements inside the TX/RX virt
queue handlers is wrong.
They are added in a per-stream invalid queue to be processed after the
handler is done examining each message, but the invalid message might
not be specifying any stream_id; which means it's invalid to add it to
any stream->invalid queue since stream could be NULL at this point.
This commit moves the invalid queue to the VirtIOSound struct which
guarantees there will always be a valid temporary place to store them
inside the tx/rx handlers. The queue will be emptied before the handler
returns, so the queue must be empty at any other point of the device's
lifetime.
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <virtio-snd-rewrite-invalid-tx-rx-message-handling-v1.manos.pitsidianakis@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch improves error handling in virtio_snd_handle_tx_xfer()
and virtio_snd_handle_rx_xfer() in the VirtIO sound driver. Previously,
'goto' statements were used for error paths, leading to unnecessary
processing and potential null pointer dereferences. Now, 'continue' is
used to skip the rest of the current loop iteration for errors such as
message size discrepancies or null streams, reducing crash risks.
ASAN log illustrating the issue addressed:
ERROR: AddressSanitizer: SEGV on unknown address 0x0000000000b4
#0 0x57cea39967b8 in qemu_mutex_lock_impl qemu/util/qemu-thread-posix.c:92:5
#1 0x57cea128c462 in qemu_mutex_lock qemu/include/qemu/thread.h:122:5
#2 0x57cea128d72f in qemu_lockable_lock qemu/include/qemu/lockable.h:95:5
#3 0x57cea128c294 in qemu_lockable_auto_lock qemu/include/qemu/lockable.h:105:5
#4 0x57cea1285eb2 in virtio_snd_handle_rx_xfer qemu/hw/audio/virtio-snd.c:1026:9
#5 0x57cea2caebbc in virtio_queue_notify_vq qemu/hw/virtio/virtio.c:2268:9
#6 0x57cea2cae412 in virtio_queue_host_notifier_read qemu/hw/virtio/virtio.c:3671:9
#7 0x57cea39822f1 in aio_dispatch_handler qemu/util/aio-posix.c:372:9
#8 0x57cea3979385 in aio_dispatch_handlers qemu/util/aio-posix.c:414:20
#9 0x57cea3978eb1 in aio_dispatch qemu/util/aio-posix.c:424:5
#10 0x57cea3a1eede in aio_ctx_dispatch qemu/util/async.c:360:5
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <20240322110827.568412-1-zheyuma97@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The payload size returned by command VIRTIO_SND_R_PCM_INFO is
wrong. The code in process_cmd() assumes that all commands
return only a virtio_snd_hdr payload, but some commands like
VIRTIO_SND_R_PCM_INFO may return an additional payload.
Add a zero initialized payload_size variable to struct
virtio_snd_ctrl_command to allow for additional payloads.
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Message-Id: <20240218083351.8524-1-vr_qemu@t-online.de>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The virtio-sound device is currently not migratable. QEMU crashes
on the source machine at some point during the migration with a
segmentation fault.
Even with this bug fixed, the virtio-sound device doesn't migrate
the state of the audio streams. For example, running streams leave
the device on the destination machine in a broken condition.
Mark the device as unmigratable until these issues have been fixed.
Signed-off-by: Volker Rümelin <vr_qemu@t-online.de>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20231204072837.6058-1-vr_qemu@t-online.de>
QEMU crashes on exit when a virtio-sound device has failed to
realise. Its vmstate field was not cleaned up properly with
qemu_del_vm_change_state_handler().
This patch changes the realize() order as
1. Validate the given configuration values (no resources allocated
by us either on success or failure)
2. Try AUD_register_card() and return on failure (no resources allocated
by us on failure)
3. Initialize vmstate, virtio device, heap allocations and stream
parameters at once.
If error occurs, goto error_cleanup label which calls
virtio_snd_unrealize(). This cleans up all resources made in steps
1-3.
Reported-by: Volker Rümelin <vr_qemu@t-online.de>
Fixes: 2880e676c0 ("Add virtio-sound device stub")
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-Id: <20231116072046.4002957-1-manos.pitsidianakis@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Handle output IO messages in the transmit (TX) virtqueue.
It allocates a VirtIOSoundPCMBuffer for each IO message and copies the
data buffer to it. When the IO buffer is written to the host's sound
card, the guest will be notified that it has been consumed.
The lifetime of an IO message is:
1. Guest sends IO message to TX virtqueue.
2. QEMU adds it to the appropriate stream's IO buffer queue.
3. Sometime later, the host audio backend calls the output callback,
virtio_snd_pcm_out_cb(), which is defined with an AUD_open_out()
call. The callback gets an available number of bytes the backend can
receive. Then it writes data from the IO buffer queue to the backend.
If at any time a buffer is exhausted, it is returned to the guest as
completed.
4. If the guest releases the stream, its buffer queue is flushed by
attempting to write any leftover data to the audio backend and
releasing all IO messages back to the guest. This is how according to
the spec the guest knows the release was successful.
Based-on: 5a2f350eec
Signed-off-by: Igor Skalkin <Igor.Skalkin@opensynergy.com>
Signed-off-by: Anton Yakovlev <Anton.Yakovlev@opensynergy.com>
Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <b7c6fc458c763d09a4abbcb620ae9b220afa5b8f.1698062525.git.manos.pitsidianakis@linaro.org>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>