Commit Graph

126 Commits

Author SHA1 Message Date
Marc-André Lureau 9edc6313da Replace GCC_FMT_ATTR with G_GNUC_PRINTF
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>
2022-03-22 14:40:51 +04:00
Stefan Hajnoczi db608fb784 virtio: unify dataplane and non-dataplane ->handle_output()
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>
2022-01-12 17:09:39 +00:00
Stefan Hajnoczi d93d16c045 virtio: get rid of VirtIOHandleAIOOutput
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>
2022-01-12 17:09:39 +00:00
Michael S. Tsirkin a882b57123 Revert "virtio: introduce macro IRTIO_CONFIG_IRQ_IDX"
This reverts commit bf1d85c166.

Fixes: bf1d85c166 ("virtio: introduce macro IRTIO_CONFIG_IRQ_IDX")
Cc: "Cindy Lu" <lulu@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-10 16:02:54 -05:00
Michael S. Tsirkin 81c3ebc32f Revert "virtio: add support for configure interrupt"
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>
2022-01-10 16:01:28 -05:00
Cindy Lu 081f864f56 virtio: add support for configure interrupt
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>
2022-01-06 06:11:39 -05:00
Cindy Lu bf1d85c166 virtio: introduce macro IRTIO_CONFIG_IRQ_IDX
To support configure interrupt for vhost-vdpa
Introduce VIRTIO_CONFIG_IRQ_IDX -1 as configure interrupt's queue index,
Then we can reuse the functions guest_notifier_mask and guest_notifier_pending.
Add the check of queue index in these drivers, if the driver does not support
configure interrupt, the function will just return

Signed-off-by: Cindy Lu <lulu@redhat.com>
Message-Id: <20211104164827.21911-2-lulu@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2022-01-06 06:11:39 -05:00
Philippe Mathieu-Daudé 4c21e3534a hw/virtio: Pass virtio_feature_get_config_size() a const argument
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>
2021-05-14 08:12:09 -04:00
Stefano Garzarella d55f518248 virtio: skip legacy support check on machine types less than 5.1
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>
2020-09-29 02:15:24 -04:00
Eduardo Habkost a489d1951c Use OBJECT_DECLARE_TYPE when possible
This converts existing DECLARE_OBJ_CHECKERS usage to
OBJECT_DECLARE_TYPE when possible.

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=AddObjectDeclareType $(git grep -l '' -- '*.[ch]')

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Paul Durrant <paul@xen.org>
Message-Id: <20200916182519.415636-5-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-18 14:12:32 -04:00
Eduardo Habkost 8110fa1d94 Use DECLARE_*CHECKER* macros
Generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=TypeCheckMacro $(git grep -l '' -- '*.[ch]')

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-12-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-13-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-14-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:27:09 -04:00
Eduardo Habkost db1015e92e Move QOM typedefs and add missing includes
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.

Patch generated using:

 $ ./scripts/codeconverter/converter.py -i \
   --pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')

which will split "typdef struct { ... } TypedefName"
declarations.

Followed by:

 $ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
    $(git grep -l '' -- '*.[ch]')

which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
2020-09-09 09:26:43 -04:00
Laurent Vivier 0c9753ebda virtio-pci: fix virtio_pci_queue_enabled()
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>
2020-07-27 11:34:50 -04:00
Cornelia Huck 7c78bdd7a3 virtio: list legacy-capable devices
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>
2020-07-22 07:57:07 -04:00
Stefan Hajnoczi d0435bc513 virtio: don't enable notifications during polling
Virtqueue notifications are not necessary during polling, so we disable
them.  This allows the guest driver to avoid MMIO vmexits.
Unfortunately the virtio-blk and virtio-scsi handler functions re-enable
notifications, defeating this optimization.

Fix virtio-blk and virtio-scsi emulation so they leave notifications
disabled.  The key thing to remember for correctness is that polling
always checks one last time after ending its loop, therefore it's safe
to lose the race when re-enabling notifications at the end of polling.

There is a measurable performance improvement of 5-10% with the null-co
block driver.  Real-life storage configurations will see a smaller
improvement because the MMIO vmexit overhead contributes less to
latency.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191209210957.65087-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-01-05 07:03:03 -05:00
Michael Roth 9d7bd0826f virtio-pci: disable vring processing when bus-mastering is disabled
Currently the SLOF firmware for pseries guests will disable/re-enable
a PCI device multiple times via IO/MEM/MASTER bits of PCI_COMMAND
register after the initial probe/feature negotiation, as it tends to
work with a single device at a time at various stages like probing
and running block/network bootloaders without doing a full reset
in-between.

In QEMU, when PCI_COMMAND_MASTER is disabled we disable the
corresponding IOMMU memory region, so DMA accesses (including to vring
fields like idx/flags) will no longer undergo the necessary
translation. Normally we wouldn't expect this to happen since it would
be misbehavior on the driver side to continue driving DMA requests.

However, in the case of pseries, with iommu_platform=on, we trigger the
following sequence when tearing down the virtio-blk dataplane ioeventfd
in response to the guest unsetting PCI_COMMAND_MASTER:

  #2  0x0000555555922651 in virtqueue_map_desc (vdev=vdev@entry=0x555556dbcfb0, p_num_sg=p_num_sg@entry=0x7fffe657e1a8, addr=addr@entry=0x7fffe657e240, iov=iov@entry=0x7fffe6580240, max_num_sg=max_num_sg@entry=1024, is_write=is_write@entry=false, pa=0, sz=0)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio.c:757
  #3  0x0000555555922a89 in virtqueue_pop (vq=vq@entry=0x555556dc8660, sz=sz@entry=184)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio.c:950
  #4  0x00005555558d3eca in virtio_blk_get_request (vq=0x555556dc8660, s=0x555556dbcfb0)
      at /home/mdroth/w/qemu.git/hw/block/virtio-blk.c:255
  #5  0x00005555558d3eca in virtio_blk_handle_vq (s=0x555556dbcfb0, vq=0x555556dc8660)
      at /home/mdroth/w/qemu.git/hw/block/virtio-blk.c:776
  #6  0x000055555591dd66 in virtio_queue_notify_aio_vq (vq=vq@entry=0x555556dc8660)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio.c:1550
  #7  0x000055555591ecef in virtio_queue_notify_aio_vq (vq=0x555556dc8660)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio.c:1546
  #8  0x000055555591ecef in virtio_queue_host_notifier_aio_poll (opaque=0x555556dc86c8)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio.c:2527
  #9  0x0000555555d02164 in run_poll_handlers_once (ctx=ctx@entry=0x55555688bfc0, timeout=timeout@entry=0x7fffe65844a8)
      at /home/mdroth/w/qemu.git/util/aio-posix.c:520
  #10 0x0000555555d02d1b in try_poll_mode (timeout=0x7fffe65844a8, ctx=0x55555688bfc0)
      at /home/mdroth/w/qemu.git/util/aio-posix.c:607
  #11 0x0000555555d02d1b in aio_poll (ctx=ctx@entry=0x55555688bfc0, blocking=blocking@entry=true)
      at /home/mdroth/w/qemu.git/util/aio-posix.c:639
  #12 0x0000555555d0004d in aio_wait_bh_oneshot (ctx=0x55555688bfc0, cb=cb@entry=0x5555558d5130 <virtio_blk_data_plane_stop_bh>, opaque=opaque@entry=0x555556de86f0)
      at /home/mdroth/w/qemu.git/util/aio-wait.c:71
  #13 0x00005555558d59bf in virtio_blk_data_plane_stop (vdev=<optimized out>)
      at /home/mdroth/w/qemu.git/hw/block/dataplane/virtio-blk.c:288
  #14 0x0000555555b906a1 in virtio_bus_stop_ioeventfd (bus=bus@entry=0x555556dbcf38)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio-bus.c:245
  #15 0x0000555555b90dbb in virtio_bus_stop_ioeventfd (bus=bus@entry=0x555556dbcf38)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio-bus.c:237
  #16 0x0000555555b92a8e in virtio_pci_stop_ioeventfd (proxy=0x555556db4e40)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio-pci.c:292
  #17 0x0000555555b92a8e in virtio_write_config (pci_dev=0x555556db4e40, address=<optimized out>, val=1048832, len=<optimized out>)
      at /home/mdroth/w/qemu.git/hw/virtio/virtio-pci.c:613

I.e. the calling code is only scheduling a one-shot BH for
virtio_blk_data_plane_stop_bh, but somehow we end up trying to process
an additional virtqueue entry before we get there. This is likely due
to the following check in virtio_queue_host_notifier_aio_poll:

  static bool virtio_queue_host_notifier_aio_poll(void *opaque)
  {
      EventNotifier *n = opaque;
      VirtQueue *vq = container_of(n, VirtQueue, host_notifier);
      bool progress;

      if (!vq->vring.desc || virtio_queue_empty(vq)) {
          return false;
      }

      progress = virtio_queue_notify_aio_vq(vq);

namely the call to virtio_queue_empty(). In this case, since no new
requests have actually been issued, shadow_avail_idx == last_avail_idx,
so we actually try to access the vring via vring_avail_idx() to get
the latest non-shadowed idx:

  int virtio_queue_empty(VirtQueue *vq)
  {
      bool empty;
      ...

      if (vq->shadow_avail_idx != vq->last_avail_idx) {
          return 0;
      }

      rcu_read_lock();
      empty = vring_avail_idx(vq) == vq->last_avail_idx;
      rcu_read_unlock();
      return empty;

but since the IOMMU region has been disabled we get a bogus value (0
usually), which causes virtio_queue_empty() to falsely report that
there are entries to be processed, which causes errors such as:

  "virtio: zero sized buffers are not allowed"

or

  "virtio-blk missing headers"

and puts the device in an error state.

This patch works around the issue by introducing virtio_set_disabled(),
which sets a 'disabled' flag to bypass checks like virtio_queue_empty()
when bus-mastering is disabled. Since we'd check this flag at all the
same sites as vdev->broken, we replace those checks with an inline
function which checks for either vdev->broken or vdev->disabled.

The 'disabled' flag is only migrated when set, which should be fairly
rare, but to maintain migration compatibility we disable it's use for
older machine types. Users requiring the use of the flag in conjunction
with older machine types can set it explicitly as a virtio-device
option.

NOTES:

 - This leaves some other oddities in play, like the fact that
   DRIVER_OK also gets unset in response to bus-mastering being
   disabled, but not restored (however the device seems to continue
   working)
 - Similarly, we disable the host notifier via
   virtio_bus_stop_ioeventfd(), which seems to move the handling out
   of virtio-blk dataplane and back into the main IO thread, and it
   ends up staying there till a reset (but otherwise continues working
   normally)

Cc: David Gibson <david@gibson.dropbear.id.au>,
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Message-Id: <20191120005003.27035-1-mdroth@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-01-05 07:03:03 -05:00
Michael S. Tsirkin 722f8c51d8 virtio: add ability to delete vq through a pointer
Devices tend to maintain vq pointers, allow deleting them trough a vq pointer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
2020-01-05 07:03:03 -05:00
Stefan Hajnoczi fcccb271e0 virtio: notify virtqueue via host notifier when available
Host notifiers are used in several cases:
1. Traditional ioeventfd where virtqueue notifications are handled in
   the main loop thread.
2. IOThreads (aio_handle_output) where virtqueue notifications are
   handled in an IOThread AioContext.
3. vhost where virtqueue notifications are handled by kernel vhost or
   a vhost-user device backend.

Most virtqueue notifications from the guest use the ioeventfd mechanism,
but there are corner cases where QEMU code calls virtio_queue_notify().
This currently honors the host notifier for the IOThreads
aio_handle_output case, but not for the vhost case.  The result is that
vhost does not receive virtqueue notifications from QEMU when
virtio_queue_notify() is called.

This patch extends virtio_queue_notify() to set the host notifier
whenever it is enabled instead of calling the vq->(aio_)handle_output()
function directly.  We track the host notifier state for each virtqueue
separately since some devices may use it only for certain virtqueues.

This fixes the vhost case although it does add a trip through the
eventfd for the traditional ioeventfd case.  I don't think it's worth
adding a fast path for the traditional ioeventfd case because calling
virtio_queue_notify() is rare when ioeventfd is enabled.

Reported-by: Felipe Franciosi <felipe@nutanix.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191105140946.165584-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-11-06 06:35:00 -05:00
Jens Freimann 9711cd0dfc net/virtio: add failover support
This patch adds support to handle failover device pairs of a virtio-net
device and a (vfio-)pci device, where the virtio-net acts as the standby
device and the (vfio-)pci device as the primary.

The general idea is that we have a pair of devices, a (vfio-)pci and a
emulated (virtio-net) device. Before migration the vfio device is
unplugged and data flows to the emulated device, on the target side
another (vfio-)pci device is plugged in to take over the data-path. In the
guest the net_failover module will pair net devices with the same MAC
address.

To achieve this we need:

1. Provide a callback function for the should_be_hidden DeviceListener.
   It is called when the primary device is plugged in. Evaluate the QOpt
   passed in to check if it is the matching primary device. It returns
   if the device should be hidden or not.
   When it should be hidden it stores the device options in the VirtioNet
   struct and the device is added once the VIRTIO_NET_F_STANDBY feature is
   negotiated during virtio feature negotiation.

   If the virtio-net devices are not realized at the time the (vfio-)pci
   devices are realized, we need to connect the devices later. This way
   we make sure primary and standby devices can be specified in any
   order.

2. Register a callback for migration status notifier. When called it
   will unplug its primary device before the migration happens.

3. Register a callback for the migration code that checks if a device
   needs to be unplugged from the guest.

Signed-off-by: Jens Freimann <jfreimann@redhat.com>
Message-Id: <20191029114905.6856-11-jfreimann@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-29 18:55:26 -04:00
Peter Maydell 1cfe28cdca -----BEGIN PGP SIGNATURE-----
Version: GnuPG v1
 
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 =uE5S
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/jasowang/tags/net-pull-request' into staging

# gpg: Signature made Tue 29 Oct 2019 02:33:36 GMT
# gpg:                using RSA key EF04965B398D6211
# gpg: Good signature from "Jason Wang (Jason Wang on RedHat) <jasowang@redhat.com>" [marginal]
# gpg: WARNING: This key is not certified with sufficiently trusted signatures!
# gpg:          It is not certain that the signature belongs to the owner.
# Primary key fingerprint: 215D 46F4 8246 689E C77F  3562 EF04 965B 398D 6211

* remotes/jasowang/tags/net-pull-request:
  COLO-compare: Fix incorrect `if` logic
  virtio-net: prevent offloads reset on migration
  virtio: new post_load hook
  net: add tulip (dec21143) driver

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-10-29 18:46:52 +00:00
Michael S. Tsirkin 1dd713837c virtio: new post_load hook
Post load hook in virtio vmsd is called early while device is processed,
and when VirtIODevice core isn't fully initialized.  Most device
specific code isn't ready to deal with a device in such state, and
behaves weirdly.

Add a new post_load hook in a device class instead.  Devices should use
this unless they specifically want to verify the migration stream as
it's processed, e.g. for bounds checking.

Cc: qemu-stable@nongnu.org
Suggested-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mikhail Sennikovsky <mikhail.sennikovskii@cloud.ionos.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2019-10-29 10:28:07 +08:00
Peter Maydell aaffb85335 Block patches for softfreeze:
- iotest patches
 - Improve performance of the mirror block job in write-blocking mode
 - Limit memory usage for the backup block job
 - Add discard and write-zeroes support to the NVMe host block driver
 - Fix a bug in the mirror job
 - Prevent the qcow2 driver from creating technically non-compliant qcow2
   v3 images (where there is not enough extra data for snapshot table
   entries)
 - Allow callers of bdrv_truncate() (etc.) to determine whether the file
   must be resized to the exact given size or whether it is OK for block
   devices not to shrink
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Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2019-10-28' into staging

Block patches for softfreeze:
- iotest patches
- Improve performance of the mirror block job in write-blocking mode
- Limit memory usage for the backup block job
- Add discard and write-zeroes support to the NVMe host block driver
- Fix a bug in the mirror job
- Prevent the qcow2 driver from creating technically non-compliant qcow2
  v3 images (where there is not enough extra data for snapshot table
  entries)
- Allow callers of bdrv_truncate() (etc.) to determine whether the file
  must be resized to the exact given size or whether it is OK for block
  devices not to shrink

# gpg: Signature made Mon 28 Oct 2019 12:13:53 GMT
# gpg:                using RSA key 91BEB60A30DB3E8857D11829F407DB0061D5CF40
# gpg:                issuer "mreitz@redhat.com"
# gpg: Good signature from "Max Reitz <mreitz@redhat.com>" [full]
# Primary key fingerprint: 91BE B60A 30DB 3E88 57D1  1829 F407 DB00 61D5 CF40

* remotes/maxreitz/tags/pull-block-2019-10-28: (69 commits)
  qemu-iotests: restrict 264 to qcow2 only
  Revert "qemu-img: Check post-truncation size"
  block: Pass truncate exact=true where reasonable
  block: Let format drivers pass @exact
  block: Evaluate @exact in protocol drivers
  block: Add @exact parameter to bdrv_co_truncate()
  block: Do not truncate file node when formatting
  block/cor: Drop cor_co_truncate()
  block: Handle filter truncation like native impl.
  iotests: Test qcow2's snapshot table handling
  iotests: Add peek_file* functions
  qcow2: Fix v3 snapshot table entry compliancy
  qcow2: Repair snapshot table with too many entries
  qcow2: Fix overly long snapshot tables
  qcow2: Keep track of the snapshot table length
  qcow2: Fix broken snapshot table entries
  qcow2: Add qcow2_check_fix_snapshot_table()
  qcow2: Separate qcow2_check_read_snapshot_table()
  qcow2: Write v3-compliant snapshot list on upgrade
  qcow2: Put qcow2_upgrade() into its own function
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2019-10-28 14:40:01 +00:00
Max Reitz 5d5b33c080 include: Move endof() up from hw/virtio/virtio.h
endof() is a useful macro, we can make use of it outside of virtio.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2019-10-28 11:51:07 +01:00
Stefan Hajnoczi 909c548c53 virtio: drop unused virtio_device_stop_ioeventfd() function
virtio_device_stop_ioeventfd() has not been used since commit
310837de6c ("virtio: introduce
grab/release_ioeventfd to fix vhost") in 2016.

Nowadays ioeventfd is stopped implicitly by the virtio transport when
lifecycle events such as the VM pausing or device unplug occur.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191021150343.30742-1-stefanha@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>
2019-10-25 07:46:22 -04:00
Jason Wang 74b3e46630 virtio: add property to enable packed virtqueue
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Message-Id: <20191025083527.30803-9-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-25 07:46:22 -04:00
Jason Wang 86044b24e8 virtio: basic packed virtqueue support
This patch implements basic support for the packed virtqueue. Compare
the split virtqueue which has three rings, packed virtqueue only have
one which is supposed to have better cache utilization and more
hardware friendly.

Please refer virtio specification for more information.

Signed-off-by: Wei Xu <wexu@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20191025083527.30803-6-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-10-25 07:46:22 -04:00
Markus Armbruster 2f780b6a91 sysemu: Move the VMChangeStateEntry typedef to qemu/typedefs.h
In my "build everything" tree, changing sysemu/sysemu.h triggers a
recompile of some 1800 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h, down from 5400 due to the
previous commit).

Several headers include sysemu/sysemu.h just to get typedef
VMChangeStateEntry.  Move it from sysemu/sysemu.h to qemu/typedefs.h.
Spell its structure tag the same while there.  Drop the now
superfluous includes of sysemu/sysemu.h from headers.

Touching sysemu/sysemu.h now recompiles some 1100 objects.
qemu/uuid.h also drops from 1800 to 1100, and
qapi/qapi-types-run-state.h from 5000 to 4400.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190812052359.30071-29-armbru@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:53 +02:00
Markus Armbruster a27bd6c779 Include hw/qdev-properties.h less
In my "build everything" tree, changing hw/qdev-properties.h triggers
a recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

Many places including hw/qdev-properties.h (directly or via hw/qdev.h)
actually need only hw/qdev-core.h.  Include hw/qdev-core.h there
instead.

hw/qdev.h is actually pointless: all it does is include hw/qdev-core.h
and hw/qdev-properties.h, which in turn includes hw/qdev-core.h.
Replace the remaining uses of hw/qdev.h by hw/qdev-properties.h.

While there, delete a few superfluous inclusions of hw/qdev-core.h.

Touching hw/qdev-properties.h now recompiles some 1200 objects.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190812052359.30071-22-armbru@redhat.com>
2019-08-16 13:31:53 +02:00
Markus Armbruster 650d103d3e Include hw/hw.h exactly where needed
In my "build everything" tree, changing hw/hw.h triggers a recompile
of some 2600 out of 6600 objects (not counting tests and objects that
don't depend on qemu/osdep.h).

The previous commits have left only the declaration of hw_error() in
hw/hw.h.  This permits dropping most of its inclusions.  Touching it
now recompiles less than 200 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-19-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Markus Armbruster d484205210 Include exec/memory.h slightly less
Drop unnecessary inclusions from headers.  Downgrade a few more to
exec/hwaddr.h.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190812052359.30071-17-armbru@redhat.com>
2019-08-16 13:31:52 +02:00
Markus Armbruster d645427057 Include migration/vmstate.h less
In my "build everything" tree, changing migration/vmstate.h triggers a
recompile of some 2700 out of 6600 objects (not counting tests and
objects that don't depend on qemu/osdep.h).

hw/hw.h supposedly includes it for convenience.  Several other headers
include it just to get VMStateDescription.  The previous commit made
that unnecessary.

Include migration/vmstate.h only where it's still needed.  Touching it
now recompiles only some 1600 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-16-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:52 +02:00
Xie Yongji 7abccd088c virtio: Set "start_on_kick" for legacy devices
Besides virtio 1.0 transitional devices, we should also
set "start_on_kick" flag for legacy devices (virtio 0.9).

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20190626023130.31315-3-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji e57f2c31b6 virtio: add "use-started" property
In order to avoid migration issues, we introduce a "use-started"
property to the base virtio device to indicate whether use
"started" flag or not. This property will be true by default and
set to false when machine type <= 4.0.

Suggested-by: Greg Kurz <groug@kaod.org>
Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Message-Id: <20190626023130.31315-2-xieyongji@baidu.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Tested-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-07-04 17:00:32 -04:00
Xie Yongji badaf79cfd virtio: Introduce started flag to VirtioDevice
The virtio 1.0 transitional devices support driver uses the device
before setting the DRIVER_OK status bit. So we introduce a started
flag to indicate whether driver has started the device or not.

Signed-off-by: Xie Yongji <xieyongji@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20190320112646.3712-2-xieyongji@baidu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-20 18:40:02 -04:00
Jason Wang 23bfaf77fa vhost_net: don't set backend for the uninitialized virtqueue
We used to set backend unconditionally, this won't work for some
guests (e.g windows driver) who may not initialize all virtqueues. For
kernel backend, this will fail since it may try to validate the rings
during setting backend.

Fixing this by simply skipping the backend set when we find desc is
not ready.

Reviewed-by: Michael S. Tsirkin<mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2019-05-17 17:00:12 +08:00
Stefano Garzarella ba550851f5 virtio-net: make VirtIOFeature usable for other virtio devices
In order to use VirtIOFeature also in other virtio devices, we move
its declaration and the endof() macro (renamed in virtio_endof())
in virtio.h.
We add virtio_feature_get_config_size() function to iterate the array
of VirtIOFeature and to return the config size depending on the
features enabled. (as virtio_net_set_config_size() did)

Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-id: 20190221103314.58500-5-sgarzare@redhat.com
Message-Id: <20190221103314.58500-5-sgarzare@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2019-02-22 09:42:16 +00:00
Tiwei Bie 6f80e6170e virtio: support setting memory region based host notifier
This patch introduces the support for setting memory region
based host notifiers for virtio device. This is helpful when
using a hardware accelerator for a virtio device, because
hardware heavily depends on the notification, this will allow
the guest driver in the VM to notify the hardware directly.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-05-23 17:01:54 +03:00
Maxime Coquelin 2d4ba6cc74 virtio: Add queue interface to restore avail index from vring used index
In case of backend crash, it is not possible to restore internal
avail index from the backend value as vhost_get_vring_base
callback fails.

This patch provides a new interface to restore internal avail index
from the vring used index, as done by some vhost-user backend on
reconnection.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-12-01 19:05:58 +02:00
Dr. David Alan Gilbert 2f168d0708 migration: Route more error paths
vmstate_save_state is called in lots of places.
Route error returns from the easier cases back up;  there are lots
of more complex cases where their own error paths need fixing.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20170925112917.21340-7-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  Commit message fix up as Peter's review
2017-09-27 11:44:18 +01:00
Maxime Coquelin 75ebec11af virtio_net: Bypass backends for MTU feature negotiation
This patch adds a new internal "x-mtu-bypass-backend" property
to bypass backends for MTU feature negotiation.

When this property is set, the MTU feature is negotiated as soon
as supported by the guest and a MTU value is set via the host_mtu
parameter. In case the backend advertises the feature (e.g. DPDK's
vhost-user backend), the feature negotiation is propagated down to
the backend.

When this property is not set, the backend has to support the MTU
feature for its negotiation to succeed.

For compatibility purpose, this property is disabled for machine
types v2.9 and older.

Cc: Aaron Conole <aconole@redhat.com>
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Reviewed-by: Vlad Yasevich <vyasevic@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-25 21:25:28 +03:00
Andrew Baumann b8adbc6578 virtio: fix vring_align() on 64-bit windows
long is 32-bits on 64-bit windows, which caused the top half of the
address to be truncated; this patch changes it to use the
QEMU_ALIGN_UP macro which does not suffer the same problem

Signed-off-by: Andrew Baumann <Andrew.Baumann@microsoft.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
2017-03-29 02:35:24 +03:00
Paolo Bonzini c611c76417 virtio: add MemoryListener to cache ring translations
The cached translations are RCU-protected to allow efficient use
when processing virtqueues.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-17 21:52:30 +02:00
Fam Zheng 0793169870 virtio: Report real progress in VQ aio poll handler
In virtio_queue_host_notifier_aio_poll, not all "!virtio_queue_empty()"
cases are making true progress.

Currently the offending one is virtio-scsi event queue, whose handler
does nothing if no event is pending. As a result aio_poll() will spin on
the "non-empty" VQ and take 100% host CPU.

Fix this by reporting actual progress from virtio queue aio handlers.

Reported-by: Ed Swierk <eswierk@skyportsystems.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Tested-by: Ed Swierk <eswierk@skyportsystems.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>
2017-02-17 21:52:30 +02:00
Paolo Bonzini c25d97c4ff virtio: make virtio_should_notify static
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-02-01 03:37:18 +02:00
Michael S. Tsirkin 8c797e758a virtio-ccw: fix ring sizing
Current code seems to assume ring size is
always decreased but this is not required by spec:
what spec says is just that size can not exceed
the maximum. Fix it up.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <1484256243-1982-1-git-send-email-mst@redhat.com>
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
2017-01-20 10:02:02 +01:00
Yuri Benditovich 54e17709ac virtio: Introduce virtqueue_drop_all procedure
Add procedure for fast drop of queued packets, acting like
pop and push without mapping the buffers into memory.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 07:02:53 +02:00
Yuri Benditovich 312d3b3534 net: Add virtio queue interface to update used index from vring state
Bring virtio queue to correct internal  state for host-to-guest
operations when vhost is temporary stopped.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 07:02:53 +02:00
Jason Wang 8607f5c307 virtio: convert to use DMA api
Currently, all virtio devices bypass IOMMU completely. This is because
address_space_memory is assumed and used during DMA emulation. This
patch converts the virtio core API to use DMA API. This idea is

- introducing a new transport specific helper to query the dma address
  space. (only pci version is implemented).
- query and use this address space during virtio device guest memory
  accessing when iommu platform (VIRTIO_F_IOMMU_PLATFORM) was enabled
  for this device.

Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Amit Shah <amit.shah@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: qemu-block@nongnu.org
Signed-off-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-01-10 05:56:58 +02:00
Paolo Bonzini 83d768b564 virtio: set ISR on dataplane notifications
Dataplane has been omitting forever the step of setting ISR when
an interrupt is raised.  This caused little breakage, because the
specification actually says that ISR may not be updated in MSI mode.

Some versions of the Windows drivers however didn't clear MSI mode
correctly, and proceeded using polling mode (using ISR, not the used
ring index!) for crashdump and hibernation.  If it were just crashdump
and hibernation it would not be a big deal, but recent releases of
Windows do not really shut down, but rather log out and hibernate to
make the next startup faster.  Hence, this manifested as a more serious
hang during shutdown with e.g. Windows 8.1 and virtio-win 1.8.0 RPMs.
Newer versions fixed this, while older versions do not use MSI at all.

The failure has always been there for virtio dataplane, but it became
visible after commits 9ffe337 ("virtio-blk: always use dataplane path
if ioeventfd is active", 2016-10-30) and ad07cd6 ("virtio-scsi: always
use dataplane path if ioeventfd is active", 2016-10-30) made virtio-blk
and virtio-scsi always use the dataplane code under KVM.  The good news
therefore is that it was not a bug in the patches---they were doing
exactly what they were meant for, i.e. shake out remaining dataplane bugs.

The fix is not hard, so it's worth arranging for the broken drivers.
The virtio_should_notify+event_notifier_set pair that is common to
virtio-blk and virtio-scsi dataplane is replaced with a new public
function virtio_notify_irqfd that also sets ISR.  The irqfd emulation
code now need not set ISR anymore, so virtio_irq is removed.

Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-18 17:29:25 +02:00
Paolo Bonzini 310837de6c virtio: introduce grab/release_ioeventfd to fix vhost
Following the recent refactoring of virtio notifiers [1], more specifically
the patch ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to
start/stop ioeventfd") that uses virtio_bus_set_host_notifier [2]
by default, core virtio code requires 'ioeventfd_started' to be set
to true/false when the host notifiers are configured.

When vhost is stopped and started, however, there is a stop followed by
another start. Since ioeventfd_started was never set to true, the 'stop'
operation triggered by virtio_bus_set_host_notifier() will not result
in a call to virtio_pci_ioeventfd_assign(assign=false). This leaves
the memory regions with stale notifiers and results on the next start
triggering the following assertion:

  kvm_mem_ioeventfd_add: error adding ioeventfd: File exists
  Aborted

This patch reintroduces (hopefully in a cleaner way) the concept
that was present with ioeventfd_disabled before the refactoring.
When ioeventfd_grabbed>0, ioeventfd_started tracks whether ioeventfd
should be enabled or not, but ioeventfd is actually not started at
all until vhost releases the host notifiers.

[1] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07748.html
[2] http://lists.nongnu.org/archive/html/qemu-devel/2016-10/msg07760.html

Reported-by: Felipe Franciosi <felipe@nutanix.com>
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Fixes: ed08a2a0b ("virtio: use virtio_bus_set_host_notifier to start/stop ioeventfd")
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Tested-by: Farhan Ali <alifm@linux.vnet.ibm.com>
Tested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-11-18 17:29:25 +02:00