Virtio 1.0 is pretty clear that features have to be
negotiated before enabling VQs. Unfortunately Seabios
ignored this ever since gaining 1.0 support (UEFI is ok).
Comment the error out for now, and add a TODO.
Fixes: 3c37f8b8d1 ("virtio: introduce virtio_queue_enable()")
Cc: "Kangjie Xu" <kangjie.xu@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20221121200339.362452-1-mst@redhat.com>
Introduce the interface queue_enable() in VirtioDeviceClass and the
fucntion virtio_queue_enable() in virtio, it can be called when
VIRTIO_PCI_COMMON_Q_ENABLE is written and related virtqueue can be
started. It only supports the devices of virtio 1 or later. The
not-supported devices can only start the virtqueue when DRIVER_OK.
Signed-off-by: Kangjie Xu <kangjie.xu@linux.alibaba.com>
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221017092558.111082-4-xuanzhuo@linux.alibaba.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Introduce a new interface function virtio_queue_reset() to implement
reset for vq.
Add a new callback to VirtioDeviceClass for queue reset operation for
each child device.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221017092558.111082-3-xuanzhuo@linux.alibaba.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Separate the logic of vq reset. This logic will be called directly
later.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20221017092558.111082-2-xuanzhuo@linux.alibaba.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This new command shows the information of a VirtQueue element.
[Note: Up until v10 of this patch series, virtio.json had many (15+)
enums defined (e.g. decoded device features, statuses, etc.). In v10
most of these enums were removed and replaced with string literals.
By doing this we get (1) simpler schema, (2) smaller generated code,
and (3) less maintenance burden for when new things are added (e.g.
devices, device features, etc.).]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-6-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
These new commands show the internal status of a VirtIODevice's
VirtQueue and a vhost device's vhost_virtqueue (if active).
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-5-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Display feature names instead of bitmaps for host, guest, and
backend for VirtIODevices.
Display status names instead of bitmaps for VirtIODevices.
Display feature names instead of bitmaps for backend, protocol,
acked, and features (hdev->features) for vhost devices.
Decode features according to device ID. Decode statuses
according to configuration status bitmap (config_status_map).
Decode vhost user protocol features according to vhost user
protocol bitmap (vhost_user_protocol_map).
Transport features are on the first line. Undecoded bits (if
any) are stored in a separate field.
[Jonah: Several changes made to this patch from prev. version (v14):
- Moved all device features mappings to hw/virtio/virtio.c
- Renamed device features mappings (less generic)
- Generalized @FEATURE_ENTRY macro for all device mappings
- Virtio device feature map definitions include descriptions of
feature bits
- Moved @VHOST_USER_F_PROTOCOL_FEATURES feature bit from transport
feature map to vhost-user-supported device feature mappings
(blk, fs, i2c, rng, net, gpu, input, scsi, vsock)
- New feature bit added for virtio-vsock: @VIRTIO_VSOCK_F_SEQPACKET
- New feature bit added for virtio-iommu: @VIRTIO_IOMMU_F_BYPASS_CONFIG
- New feature bit added for virtio-mem: @VIRTIO_MEM_F_UNPLUGGED_INACCESSIBLE
- New virtio transport feature bit added: @VIRTIO_F_IN_ORDER
- Added device feature map definition for virtio-rng
]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-4-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This new command shows the status of a VirtIODevice, including
its corresponding vhost device's status (if active).
Next patch will improve output by decoding feature bits, including
vhost device's feature bits (backend, protocol, acked, and features).
Also will decode status bits of a VirtIODevice.
[Jonah: From patch v12; added a check to @virtio_device_find to ensure
synchronicity between @virtio_list and the devices in the QOM
composition tree.]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-3-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This new command lists all the instances of VirtIODevices with
their canonical QOM path and name.
[Jonah: @virtio_list duplicates information that already exists in
the QOM composition tree. However, extracting necessary information
from this tree seems to be a bit convoluted.
Instead, we still create our own list of realized virtio devices
but use @qmp_qom_get with the device's canonical QOM path to confirm
that the device exists and is realized. If the device exists but
is actually not realized, then we remove it from our list (for
synchronicity to the QOM composition tree).
Also, the QMP command @x-query-virtio is redundant as @qom-list
and @qom-get are sufficient to search '/machine/' for realized
virtio devices. However, @x-query-virtio is much more convenient
in listing realized virtio devices.]
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1660220684-24909-2-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This is the first step towards moving all device config size calculation
logic into the virtio core code. In particular, this adds a struct that
contains all the necessary information for common virtio code to be able
to calculate the final config size for a device. This is expected to be
used with the new virtio_get_config_size helper, which calculates the
final length based on the provided host features.
This builds on top of already existing code like VirtIOFeature and
virtio_feature_get_config_size(), but adds additional fields, as well as
sanity checking so that device-specifc code doesn't have to duplicate it.
An example usage would be:
static const VirtIOFeature dev_features[] = {
{.flags = 1ULL << FEATURE_1_BIT,
.end = endof(struct virtio_dev_config, feature_1)},
{.flags = 1ULL << FEATURE_2_BIT,
.end = endof(struct virtio_dev_config, feature_2)},
{}
};
static const VirtIOConfigSizeParams dev_cfg_size_params = {
.min_size = DEV_BASE_CONFIG_SIZE,
.max_size = sizeof(struct virtio_dev_config),
.feature_sizes = dev_features
};
// code inside my_dev_device_realize()
size_t config_size = virtio_get_config_size(&dev_cfg_size_params,
host_features);
virtio_init(vdev, VIRTIO_ID_MYDEV, config_size);
Currently every device is expected to write its own boilerplate from the
example above in device_realize(), however, the next step of this
transition is moving VirtIOConfigSizeParams into VirtioDeviceClass,
so that it can be done automatically by the virtio initialization code.
All of the users of virtio_feature_get_config_size have been converted
to use virtio_get_config_size so it's no longer needed and is removed
with this commit.
Signed-off-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Message-Id: <20220906073111.353245-2-d-tatianin@yandex-team.ru>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If the guest driver attempts to use the UNUSED(30) bit it is
potentially buggy as 6.3 Legacy Interface: Reserved Feature Bits
states it "SHOULD NOT be negotiated". For now just log this guest
error.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220802095010.3330793-9-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch adds a get_vhost() callback function for VirtIODevices that
returns the device's corresponding vhost_dev structure, if the vhost
device is running. This patch also adds a vhost_started flag for
VirtIODevices.
Previously, a VirtIODevice wouldn't be able to tell if its corresponding
vhost device was active or not.
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1648819405-25696-3-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch drops the name parameter for the virtio_init function.
The pair between the numeric device ID and the string device ID
(name) of a virtio device already exists, but not in a way that
lets us map between them.
This patch lets us do this and removes the need for the name
parameter in the virtio_init function.
Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1648819405-25696-2-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The virtio-scsi event virtqueue is not emptied by its handler function.
This is typical for rx virtqueues where the device uses buffers when
some event occurs (e.g. a packet is received, an error condition
happens, etc).
Polling non-empty virtqueues wastes CPU cycles. We are not waiting for
new buffers to become available, we are waiting for an event to occur,
so it's a misuse of CPU resources to poll for buffers.
Introduce the new virtio_queue_aio_attach_host_notifier_no_poll() API,
which is identical to virtio_queue_aio_attach_host_notifier() except
that it does not poll the virtqueue.
Before this patch the following command-line consumed 100% CPU in the
IOThread polling and calling virtio_scsi_handle_event():
$ qemu-system-x86_64 -M accel=kvm -m 1G -cpu host \
--object iothread,id=iothread0 \
--device virtio-scsi-pci,iothread=iothread0 \
--blockdev file,filename=test.img,aio=native,cache.direct=on,node-name=drive0 \
--device scsi-hd,drive=drive0
After this patch CPU is no longer wasted.
Reported-by: Nir Soffer <nsoffer@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Nir Soffer <nsoffer@redhat.com>
Message-id: 20220427143541.119567-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
One less qemu-specific macro. It also helps to make some headers/units
only depend on glib, and thus moved in standalone projects eventually.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.
This commit only touches allocations with size arguments of the form
sizeof(T).
Patch created mechanically with:
$ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
--macro-file scripts/cocci-macro-file.h FILES...
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
The migration code will not look at a VMStateDescription's
minimum_version_id_old field unless that VMSD has set the
load_state_old field to something non-NULL. (The purpose of
minimum_version_id_old is to specify what migration version is needed
for the code in the function pointed to by load_state_old to be able
to handle it on incoming migration.)
We have exactly one VMSD which still has a load_state_old,
in the PPC CPU; every other VMSD which sets minimum_version_id_old
is doing so unnecessarily. Delete all the unnecessary ones.
Commit created with:
sed -i '/\.minimum_version_id_old/d' $(git grep -l '\.minimum_version_id_old')
with the one legitimate use then hand-edited back in.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
It missed vmstate_ppc_cpu.
Now that virtio-blk and virtio-scsi are ready, get rid of
the handle_aio_output() callback. It's no longer needed.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-7-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The difference between ->handle_output() and ->handle_aio_output() was
that ->handle_aio_output() returned a bool return value indicating
progress. This was needed by the old polling API but now that the bool
return value is gone, the two functions can be unified.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-6-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
The virtqueue host notifier API
virtio_queue_aio_set_host_notifier_handler() polls the virtqueue for new
buffers. AioContext previously required a bool progress return value
indicating whether an event was handled or not. This is no longer
necessary because the AioContext polling API has been split into a poll
check function and an event handler function. The event handler is only
run when we know there is work to do, so it doesn't return bool.
The VirtIOHandleAIOOutput function signature is now the same as
VirtIOHandleOutput. Get rid of the bool return value.
Further simplifications will be made for virtio-blk and virtio-scsi in
the next patch.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-3-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Adaptive polling measures the execution time of the polling check plus
handlers called when a polled event becomes ready. Handlers can take a
significant amount of time, making it look like polling was running for
a long time when in fact the event handler was running for a long time.
For example, on Linux the io_submit(2) syscall invoked when a virtio-blk
device's virtqueue becomes ready can take 10s of microseconds. This
can exceed the default polling interval (32 microseconds) and cause
adaptive polling to stop polling.
By excluding the handler's execution time from the polling check we make
the adaptive polling calculation more accurate. As a result, the event
loop now stays in polling mode where previously it would have fallen
back to file descriptor monitoring.
The following data was collected with virtio-blk num-queues=2
event_idx=off using an IOThread. Before:
168k IOPS, IOThread syscalls:
9837.115 ( 0.020 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 16, iocbpp: 0x7fcb9f937db0) = 16
9837.158 ( 0.002 ms): IO iothread1/620155 write(fd: 103, buf: 0x556a2ef71b88, count: 8) = 8
9837.161 ( 0.001 ms): IO iothread1/620155 write(fd: 104, buf: 0x556a2ef71b88, count: 8) = 8
9837.163 ( 0.001 ms): IO iothread1/620155 ppoll(ufds: 0x7fcb90002800, nfds: 4, tsp: 0x7fcb9f1342d0, sigsetsize: 8) = 3
9837.164 ( 0.001 ms): IO iothread1/620155 read(fd: 107, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.174 ( 0.001 ms): IO iothread1/620155 read(fd: 105, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.176 ( 0.001 ms): IO iothread1/620155 read(fd: 106, buf: 0x7fcb9f939cc0, count: 512) = 8
9837.209 ( 0.035 ms): IO iothread1/620155 io_submit(ctx_id: 140512552468480, nr: 32, iocbpp: 0x7fca7d0cebe0) = 32
174k IOPS (+3.6%), IOThread syscalls:
9809.566 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0cdd62be0) = 32
9809.625 ( 0.001 ms): IO iothread1/623061 write(fd: 103, buf: 0x5647cfba5f58, count: 8) = 8
9809.627 ( 0.002 ms): IO iothread1/623061 write(fd: 104, buf: 0x5647cfba5f58, count: 8) = 8
9809.663 ( 0.036 ms): IO iothread1/623061 io_submit(ctx_id: 140539805028352, nr: 32, iocbpp: 0x7fd0d0388b50) = 32
Notice that ppoll(2) and eventfd read(2) syscalls are eliminated because
the IOThread stays in polling mode instead of falling back to file
descriptor monitoring.
As usual, polling is not implemented on Windows so this patch ignores
the new io_poll_read() callback in aio-win32.c.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20211207132336.36627-2-stefanha@redhat.com
[Fixed up aio_set_event_notifier() calls in
tests/unit/test-fdmon-epoll.c added after this series was queued.
--Stefan]
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This reverts commit 081f864f56.
Fixes: 081f864f56 ("virtio: add support for configure interrupt")
Cc: "Cindy Lu" <lulu@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Packed Virtqueues wrap used_idx instead of letting it run freely like
Split Virtqueues do. If the used ring wraps more than once there is no
way to compare vq->signalled_used and vq->used_idx in
virtio_packed_should_notify() since they are modulo vq->vring.num.
This causes the device to stop sending used buffer notifications when
when virtio_packed_should_notify() is called less than once each time
around the used ring.
It is possible to trigger this with virtio-blk's dataplane
notify_guest_bh() irq coalescing optimization. The call to
virtio_notify_irqfd() (and virtio_packed_should_notify()) is deferred to
a BH. If the guest driver is polling it can complete and submit more
requests before the BH executes, causing the used ring to wrap more than
once. The result is that the virtio-blk device ceases to raise
interrupts and I/O hangs.
Cc: Tiwei Bie <tiwei.bie@intel.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20211130134510.267382-1-stefanha@redhat.com>
Fixes: 86044b24e8 ("virtio: basic packed virtqueue support")
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add the functions to support the configure interrupt in virtio
The function virtio_config_guest_notifier_read will notify the
guest if there is an configure interrupt.
The function virtio_config_set_guest_notifier_fd_handler is
to set the fd hander for the notifier
Signed-off-by: Cindy Lu <lulu@redhat.com>
Message-Id: <20211104164827.21911-7-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Let devices specify transaction attributes when calling
dma_memory_map().
Patch created mechanically using spatch with this script:
@@
expression E1, E2, E3, E4;
@@
- dma_memory_map(E1, E2, E3, E4)
+ dma_memory_map(E1, E2, E3, E4, MEMTXATTRS_UNSPECIFIED)
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20211223115554.3155328-7-philmd@redhat.com>
We used to access packed descriptor event and off_wrap via
address_space_{write|read}_cached(). When we hit the cache, memcpy()
is used which is not atomic which may lead a wrong value to be read or
wrote.
This patch fixes this by switching to use
virito_{stw|lduw}_phys_cached() to make sure the access is atomic.
Fixes: 683f766567 ("virtio: event suppression support for packed ring")
Cc: qemu-stable@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20211111063854.29060-2-jasowang@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
We used to access packed descriptor flags via
address_space_{write|read}_cached(). When we hit the cache, memcpy()
is used which is not an atomic operation which may lead a wrong value
is read or wrote.
So this patch switches to use virito_{stw|lduw}_phys_cached() to make
sure the aceess is atomic.
Fixes: 86044b24e8 ("virtio: basic packed virtqueue support")
Cc: qemu-stable@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20211111063854.29060-1-jasowang@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Both virtqueue_packed_get_avail_bytes() and
virtqueue_split_get_avail_bytes() access the region cache, but
their caller also does. Simplify by having virtqueue_get_avail_bytes
calling both with RCU lock held, and passing the caches as argument.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210906104318.1569967-4-philmd@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
vring_get_region_caches() must be called with the RCU read lock
acquired. virtqueue_packed_drop_all() does not, and uses the
'caches' pointer. Fix that by using the RCU_READ_LOCK_GUARD()
macro.
Reported-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210906104318.1569967-3-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Provide a name field for all the memory listeners. It can be used to identify
which memory listener is which.
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210817013553.30584-2-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
virtio_free_region_cache() is called within call_rcu(),
always with a non-NULL argument. Ensure new code keep it
that way by replacing the NULL check by an assertion.
Add a comment this function is called within call_rcu().
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210826172658.2116840-3-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
While virtio_queue_packed_empty_rcu() uses the '_rcu' suffix,
it is not obvious it is called within rcu_read_lock(). All other
functions from this file called with the RCU locked have a comment
describing it. Document this one similarly for consistency.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210826172658.2116840-2-philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
The device model batching its ioeventfds in a single MR transaction is
an optimization. Clarify this in virtio-scsi, virtio-blk and generic
virtio code. Also clarify that the transaction must commit before
closing ioeventfds so that no one is tempted to merge the loops
in the start functions error path and in the stop functions.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <162125799728.1394228.339855768563326832.stgit@bahia.lan>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Introduce the cpu_virtio_is_big_endian() generic helper to avoid
calling CPUClass internal virtio_is_big_endian() one.
Similarly to commit bf7663c4bd ("cpu: introduce
CPUClass::virtio_is_big_endian()"), we keep 'virtio' in the method
name to hint this handler shouldn't be called anywhere but from the
virtio code.
Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210517105140.1062037-8-f4bug@amsat.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Fixes all over the place. Faster boot for virtio. ioeventfd support for
mmio.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging
pc,pci,virtio: bugfixes, improvements
Fixes all over the place. Faster boot for virtio. ioeventfd support for
mmio.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# gpg: Signature made Fri 14 May 2021 15:27:13 BST
# gpg: using RSA key 5D09FD0871C8F85B94CA8A0D281F0DB8D28D5469
# gpg: issuer "mst@redhat.com"
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>" [full]
# gpg: aka "Michael S. Tsirkin <mst@redhat.com>" [full]
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17 0970 C350 3912 AFBE 8E67
# Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA 8A0D 281F 0DB8 D28D 5469
* remotes/mst/tags/for_upstream:
Fix build with 64 bits time_t
vhost-vdpa: Make vhost_vdpa_get_device_id() static
hw/virtio: enable ioeventfd configuring for mmio
hw/smbios: support for type 41 (onboard devices extended information)
checkpatch: Fix use of uninitialized value
virtio-scsi: Configure all host notifiers in a single MR transaction
virtio-scsi: Set host notifiers and callbacks separately
virtio-blk: Configure all host notifiers in a single MR transaction
virtio-blk: Fix rollback path in virtio_blk_data_plane_start()
pc-dimm: remove unnecessary get_vmstate_memory_region() method
amd_iommu: fix wrong MMIO operations
virtio-net: Constify VirtIOFeature feature_sizes[]
virtio-blk: Constify VirtIOFeature feature_sizes[]
hw/virtio: Pass virtio_feature_get_config_size() a const argument
x86: acpi: use offset instead of pointer when using build_header()
amd_iommu: Fix pte_override_page_mask()
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
# Conflicts:
# hw/arm/virt.c
The VirtIOFeature structure isn't modified, mark it const.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210511104157.2880306-2-philmd@redhat.com>
Stop including exec/address-spaces.h in files that don't need it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210416171314.2074665-5-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
The 'running' argument from VMChangeStateHandler does not require
other value than 0 / 1. Make it a plain boolean.
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20210111152020.1422021-3-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Address space is destroyed without proper removal of its listeners with
current code. They are expected to be removed in
virtio_device_instance_finalize [1], but qemu calls it through
object_deinit, after address_space_destroy call through
device_set_realized [2].
Move it to virtio_device_unrealize, called before device_set_realized
[3] and making it symmetric with memory_listener_register in
virtio_device_realize.
v2: Delete no-op call of virtio_device_instance_finalize.
Add backtraces.
[1]
#0 virtio_device_instance_finalize (obj=0x555557de5120)
at /home/qemu/include/hw/virtio/virtio.h:71
#1 0x0000555555b703c9 in object_deinit (type=0x555556639860,
obj=<optimized out>) at ../qom/object.c:671
#2 object_finalize (data=0x555557de5120) at ../qom/object.c:685
#3 object_unref (objptr=0x555557de5120) at ../qom/object.c:1184
#4 0x0000555555b4de9d in bus_free_bus_child (kid=0x555557df0660)
at ../hw/core/qdev.c:55
#5 0x0000555555c65003 in call_rcu_thread (opaque=opaque@entry=0x0)
at ../util/rcu.c:281
Queued by:
#0 bus_remove_child (bus=0x555557de5098,
child=child@entry=0x555557de5120) at ../hw/core/qdev.c:60
#1 0x0000555555b4ee31 in device_unparent (obj=<optimized out>)
at ../hw/core/qdev.c:984
#2 0x0000555555b70465 in object_finalize_child_property (
obj=<optimized out>, name=<optimized out>, opaque=0x555557de5120)
at ../qom/object.c:1725
#3 0x0000555555b6fa17 in object_property_del_child (
child=0x555557de5120, obj=0x555557ddcf90) at ../qom/object.c:645
#4 object_unparent (obj=0x555557de5120) at ../qom/object.c:664
#5 0x0000555555b4c071 in bus_unparent (obj=<optimized out>)
at ../hw/core/bus.c:147
#6 0x0000555555b70465 in object_finalize_child_property (
obj=<optimized out>, name=<optimized out>, opaque=0x555557de5098)
at ../qom/object.c:1725
#7 0x0000555555b6fa17 in object_property_del_child (
child=0x555557de5098, obj=0x555557ddcf90) at ../qom/object.c:645
#8 object_unparent (obj=0x555557de5098) at ../qom/object.c:664
#9 0x0000555555b4ee19 in device_unparent (obj=<optimized out>)
at ../hw/core/qdev.c:981
#10 0x0000555555b70465 in object_finalize_child_property (
obj=<optimized out>, name=<optimized out>, opaque=0x555557ddcf90)
at ../qom/object.c:1725
#11 0x0000555555b6fa17 in object_property_del_child (
child=0x555557ddcf90, obj=0x55555685da10) at ../qom/object.c:645
#12 object_unparent (obj=0x555557ddcf90) at ../qom/object.c:664
#13 0x00005555558dc331 in pci_for_each_device_under_bus (
opaque=<optimized out>, fn=<optimized out>, bus=<optimized out>)
at ../hw/pci/pci.c:1654
[2]
Optimizer omits pci_qdev_unrealize, called by device_set_realized, and
do_pci_unregister_device, called by pci_qdev_unrealize and caller of
address_space_destroy.
#0 address_space_destroy (as=0x555557ddd1b8)
at ../softmmu/memory.c:2840
#1 0x0000555555b4fc53 in device_set_realized (obj=0x555557ddcf90,
value=<optimized out>, errp=0x7fffeea8f1e0)
at ../hw/core/qdev.c:850
#2 0x0000555555b6eaa6 in property_set_bool (obj=0x555557ddcf90,
v=<optimized out>, name=<optimized out>, opaque=0x555556650ba0,
errp=0x7fffeea8f1e0) at ../qom/object.c:2255
#3 0x0000555555b70e07 in object_property_set (
obj=obj@entry=0x555557ddcf90,
name=name@entry=0x555555db99df "realized",
v=v@entry=0x7fffe46b7500,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1400
#4 0x0000555555b73c5f in object_property_set_qobject (
obj=obj@entry=0x555557ddcf90,
name=name@entry=0x555555db99df "realized",
value=value@entry=0x7fffe44f6180,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/qom-qobject.c:28
#5 0x0000555555b71044 in object_property_set_bool (
obj=0x555557ddcf90, name=0x555555db99df "realized",
value=<optimized out>, errp=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1470
#6 0x0000555555921cb7 in pcie_unplug_device (bus=<optimized out>,
dev=0x555557ddcf90,
opaque=<optimized out>) at /home/qemu/include/hw/qdev-core.h:17
#7 0x00005555558dc331 in pci_for_each_device_under_bus (
opaque=<optimized out>, fn=<optimized out>,
bus=<optimized out>) at ../hw/pci/pci.c:1654
[3]
#0 virtio_device_unrealize (dev=0x555557de5120)
at ../hw/virtio/virtio.c:3680
#1 0x0000555555b4fc63 in device_set_realized (obj=0x555557de5120,
value=<optimized out>, errp=0x7fffee28df90)
at ../hw/core/qdev.c:850
#2 0x0000555555b6eab6 in property_set_bool (obj=0x555557de5120,
v=<optimized out>, name=<optimized out>, opaque=0x555556650ba0,
errp=0x7fffee28df90) at ../qom/object.c:2255
#3 0x0000555555b70e17 in object_property_set (
obj=obj@entry=0x555557de5120,
name=name@entry=0x555555db99ff "realized",
v=v@entry=0x7ffdd8035040,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1400
#4 0x0000555555b73c6f in object_property_set_qobject (
obj=obj@entry=0x555557de5120,
name=name@entry=0x555555db99ff "realized",
value=value@entry=0x7ffdd8035020,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/qom-qobject.c:28
#5 0x0000555555b71054 in object_property_set_bool (
obj=0x555557de5120, name=name@entry=0x555555db99ff "realized",
value=value@entry=false, errp=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1470
#6 0x0000555555b4edc5 in qdev_unrealize (dev=<optimized out>)
at ../hw/core/qdev.c:403
#7 0x0000555555b4c2a9 in bus_set_realized (obj=<optimized out>,
value=<optimized out>, errp=<optimized out>)
at ../hw/core/bus.c:204
#8 0x0000555555b6eab6 in property_set_bool (obj=0x555557de5098,
v=<optimized out>, name=<optimized out>, opaque=0x555557df04c0,
errp=0x7fffee28e0a0) at ../qom/object.c:2255
#9 0x0000555555b70e17 in object_property_set (
obj=obj@entry=0x555557de5098,
name=name@entry=0x555555db99ff "realized",
v=v@entry=0x7ffdd8034f50,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1400
#10 0x0000555555b73c6f in object_property_set_qobject (
obj=obj@entry=0x555557de5098,
name=name@entry=0x555555db99ff "realized",
value=value@entry=0x7ffdd8020630,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/qom-qobject.c:28
#11 0x0000555555b71054 in object_property_set_bool (
obj=obj@entry=0x555557de5098,
name=name@entry=0x555555db99ff "realized",
value=value@entry=false, errp=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1470
#12 0x0000555555b4c725 in qbus_unrealize (
bus=bus@entry=0x555557de5098) at ../hw/core/bus.c:178
#13 0x0000555555b4fc00 in device_set_realized (obj=0x555557ddcf90,
value=<optimized out>, errp=0x7fffee28e1e0)
at ../hw/core/qdev.c:844
#14 0x0000555555b6eab6 in property_set_bool (obj=0x555557ddcf90,
v=<optimized out>, name=<optimized out>, opaque=0x555556650ba0,
errp=0x7fffee28e1e0) at ../qom/object.c:2255
#15 0x0000555555b70e17 in object_property_set (
obj=obj@entry=0x555557ddcf90,
name=name@entry=0x555555db99ff "realized",
v=v@entry=0x7ffdd8020560,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1400
#16 0x0000555555b73c6f in object_property_set_qobject (
obj=obj@entry=0x555557ddcf90,
name=name@entry=0x555555db99ff "realized",
value=value@entry=0x7ffdd8020540,
errp=errp@entry=0x5555565bbf38 <error_abort>)
at ../qom/qom-qobject.c:28
#17 0x0000555555b71054 in object_property_set_bool (
obj=0x555557ddcf90, name=0x555555db99ff "realized",
value=<optimized out>, errp=0x5555565bbf38 <error_abort>)
at ../qom/object.c:1470
#18 0x0000555555921cb7 in pcie_unplug_device (bus=<optimized out>,
dev=0x555557ddcf90, opaque=<optimized out>)
at /home/qemu/include/hw/qdev-core.h:17
#19 0x00005555558dc331 in pci_for_each_device_under_bus (
opaque=<optimized out>, fn=<optimized out>, bus=<optimized out>)
at ../hw/pci/pci.c:1654
Fixes: c611c76417 ("virtio: add MemoryListener to cache ring translations")
Buglink: https://bugs.launchpad.net/qemu/+bug/1912846
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20210125192505.390554-1-eperezma@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Commit 8118f0950f "migration: Append JSON description of migration
stream" needs a JSON writer. The existing qobject_to_json() wasn't a
good fit, because it requires building a QObject to convert. Instead,
migration got its very own JSON writer, in commit 190c882ce2 "QJSON:
Add JSON writer". It tacitly limits numbers to int64_t, and strings
contents to characters that don't need escaping, unlike
qobject_to_json().
The previous commit factored the JSON writer out of qobject_to_json().
Replace migration's JSON writer by it.
Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201211171152.146877-17-armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
If we find a queue with an inconsistent guest index value, explicitly mark the
device as needing a reset - and broken - via virtio_error().
There's at least one driver implementation - the virtio-win NetKVM driver - that
is able to handle a VIRTIO_CONFIG_S_NEEDS_RESET notification and successfully
restore the device to a working state. Other implementations do not correctly
handle this, but as the VQ is not in a functional state anyway, this is still
worth doing.
Signed-off-by: John Levon <john.levon@nutanix.com>
Message-Id: <20201120185103.GA442386@sent>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
QEMU must be careful when loading device state off migration streams to
prevent a malicious source from exploiting the emulator. Overdoing these
checks has the side effect of allowing a guest to "pin itself" in cloud
environments by messing with state which is entirely in its control.
Similarly to what f3081539 achieved in usb_device_post_load(), this
commit removes such a check from virtio_load(). Worth noting, the result
of a load without this check is the same as if a guest enables a VQ with
invalid indexes to begin with. That is, the virtual device is set in a
broken state (by the datapath handler) and must be reset.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Message-Id: <20201028134643.110698-1-felipe@nutanix.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Current the 'virtio_set_features' only update the 'MemorRegionCaches'
when the 'virtio_set_features_nocheck' return '0' which means it is
not bad features. However the guest can still trigger the access of the
used vring after set bad features. In this situation it will cause assert
failure in 'ADDRESS_SPACE_ST_CACHED'.
Buglink: https://bugs.launchpad.net/qemu/+bug/1890333
Fixes: db812c4073 ("virtio: update MemoryRegionCaches when guest negotiates features")
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20200919082706.6703-1-liq3ea@163.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Commit 9b3a35ec82 ("virtio: verify that legacy support is not accidentally
on") added a check that returns an error if legacy support is on, but the
device does not support legacy.
Unfortunately some devices were wrongly declared legacy capable even if
they were not (e.g vhost-vsock).
To avoid migration issues, we add a virtio-device property
(x-disable-legacy-check) to skip the legacy error, printing a warning
instead, for machine types < 5.1.
Cc: qemu-stable@nongnu.org
Fixes: 9b3a35ec82 ("virtio: verify that legacy support is not accidentally on")
Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Suggested-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20200921122506.82515-2-sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
clang's C11 atomic_fetch_*() functions only take a C11 atomic type
pointer argument. QEMU uses direct types (int, etc) and this causes a
compiler error when a QEMU code calls these functions in a source file
that also included <stdatomic.h> via a system header file:
$ CC=clang CXX=clang++ ./configure ... && make
../util/async.c:79:17: error: address argument to atomic operation must be a pointer to _Atomic type ('unsigned int *' invalid)
Avoid using atomic_*() names in QEMU's atomic.h since that namespace is
used by <stdatomic.h>. Prefix QEMU's APIs with 'q' so that atomic.h
and <stdatomic.h> can co-exist. I checked /usr/include on my machine and
searched GitHub for existing "qatomic_" users but there seem to be none.
This patch was generated using:
$ git grep -h -o '\<atomic\(64\)\?_[a-z0-9_]\+' include/qemu/atomic.h | \
sort -u >/tmp/changed_identifiers
$ for identifier in $(</tmp/changed_identifiers); do
sed -i "s%\<$identifier\>%q$identifier%g" \
$(git grep -I -l "\<$identifier\>")
done
I manually fixed line-wrap issues and misaligned rST tables.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200923105646.47864-1-stefanha@redhat.com>
In legacy mode, virtio_pci_queue_enabled() falls back to
virtio_queue_enabled() to know if the queue is enabled.
But virtio_queue_enabled() calls again virtio_pci_queue_enabled()
if k->queue_enabled is set. This ends in a crash after a stack
overflow.
The problem can be reproduced with
"-device virtio-net-pci,disable-legacy=off,disable-modern=true
-net tap,vhost=on"
And a look to the backtrace is very explicit:
...
#4 0x000000010029a438 in virtio_queue_enabled ()
#5 0x0000000100497a9c in virtio_pci_queue_enabled ()
...
#130902 0x000000010029a460 in virtio_queue_enabled ()
#130903 0x0000000100497a9c in virtio_pci_queue_enabled ()
#130904 0x000000010029a460 in virtio_queue_enabled ()
#130905 0x0000000100454a20 in vhost_net_start ()
...
This patch fixes the problem by introducing a new function
for the legacy case and calls it from virtio_pci_queue_enabled().
It also calls it from virtio_queue_enabled() to avoid code duplication.
Fixes: f19bcdfedd ("virtio-pci: implement queue_enabled method")
Cc: Jason Wang <jasowang@redhat.com>
Cc: Cindy Lu <lulu@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20200727153319.43716-1-lvivier@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Several types of virtio devices had already been around before the
virtio standard was specified. These devices support virtio in legacy
(and transitional) mode.
Devices that have been added in the virtio standard are considered
non-transitional (i.e. with no support for legacy virtio).
Provide a helper function so virtio transports can figure that out
easily.
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200707105446.677966-2-cohuck@redhat.com>
Cc: qemu-stable@nongnu.org
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch introduces queue_enabled() method which allows the
transport to implement its own way to report whether or not a queue is
enabled.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Cindy Lu <lulu@redhat.com>
Message-Id: <20200701145538.22333-4-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
