The subsection name for page-poison was typo'd as:
vitio-balloon-device/page-poison
Note the missing 'r' in virtio.
When we have a machine type that enables page poison, and the guest
enables it (which needs a new kernel), things fail rather unpredictably.
The fallout from this is that most of the other subsections fail to
load, including things like the feature bits in the device, one
possible fallout is that the physical addresses of the queues
then get aligned differently and we fail with an error about
last_avail_idx being wrong.
It's not obvious to me why this doesn't produce a more obvious failure,
but virtio's vmstate loading is a bit open-coded.
Fixes: 7483cbbaf8 ("virtio-balloon: Implement support for page poison reporting feature")
bz: https://bugzilla.redhat.com/show_bug.cgi?id=1984401
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20210914131716.102851-1-dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
virtio-vsock features, like VIRTIO_VSOCK_F_SEQPACKET, can be handled
by vhost-vsock-common parent class. In this way, we can reuse the
same code for all virtio-vsock backends (i.e. vhost-vsock,
vhost-user-vsock).
Let's move `seqpacket` property to vhost-vsock-common class, add
vhost_vsock_common_get_features() used by children, and disable
`seqpacket` for vhost-user-vsock device for machine types < 6.2.
The behavior of vhost-vsock device doesn't change; vhost-user-vsock
device now supports `seqpacket` property.
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20210921161642.206461-3-sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Commit 1e08fd0a46 ("vhost-vsock: SOCK_SEQPACKET feature bit support")
enabled the SEQPACKET feature bit.
This commit is released with QEMU 6.1, so if we try to migrate a VM where
the host kernel supports SEQPACKET but machine type version is less than
6.1, we get the following errors:
Features 0x130000002 unsupported. Allowed features: 0x179000000
Failed to load virtio-vhost_vsock:virtio
error while loading state for instance 0x0 of device '0000:00:05.0/virtio-vhost_vsock'
load of migration failed: Operation not permitted
Let's disable the feature bit for machine types < 6.1.
We add a new OnOffAuto property for this, called `seqpacket`.
When it is `auto` (default), QEMU behaves as before, trying to enable the
feature, when it is `on` QEMU will fail if the backend (vhost-vsock
kernel module) doesn't support it.
Fixes: 1e08fd0a46 ("vhost-vsock: SOCK_SEQPACKET feature bit support")
Cc: qemu-stable@nongnu.org
Reported-by: Jiang Wang <jiang.wang@bytedance.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20210921161642.206461-2-sgarzare@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>
As we might not always have a device id, it is impossible to always
match MEMORY_DEVICE_SIZE_CHANGE events to an actual device. Let's
include the qom-path in the event, which allows for reliable mapping of
events to devices.
Fixes: 722a3c783e ("virtio-pci: Send qapi events when the virtio-mem size changes")
Suggested-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210929162445.64060-3-david@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>
Vhost used to compare the dma_as against the address_space_memory to
detect whether the IOMMU is enabled or not. This might not work well
since the virito-bus may call get_dma_as if VIRTIO_F_IOMMU_PLATFORM is
set without an actual IOMMU enabled when device is plugged. In the
case of PCI where pci_get_address_space() is used, the bus master as
is returned. So vhost actually tries to enable device IOTLB even if
the IOMMU is not enabled. This will lead a lots of unnecessary
transactions between vhost and Qemu and will introduce a huge drop of
the performance.
For PCI, an ideal approach is to use pci_device_iommu_address_space()
just for get_dma_as. But Qemu may choose to initialize the IOMMU after
the virtio-pci which lead a wrong address space is returned during
device plugged. So this patch switch to use transport specific way via
iommu_enabled() to detect the IOMMU during vhost start. In this case,
we are fine since we know the IOMMU is initialized correctly.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20210804034803.1644-4-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch implements the PCI transport version of iommu_enabled. This
is done by comparing the address space returned by
pci_device_iommu_address_space() against address_space_memory.
Note that an ideal approach is to use pci_device_iommu_address_space()
in get_dma_as(), but it might not work well since the IOMMU could be
initialized after the virtio-pci device is initialized.
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20210804034803.1644-3-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Postcopy never worked properly with 'free-page-hint=on', as there are
at least two issues:
1) With postcopy, the guest will never receive a VIRTIO_BALLOON_CMD_ID_DONE
and consequently won't release free pages back to the OS once
migration finishes.
The issue is that for postcopy, we won't do a final bitmap sync while
the guest is stopped on the source and
virtio_balloon_free_page_hint_notify() will only call
virtio_balloon_free_page_done() on the source during
PRECOPY_NOTIFY_CLEANUP, after the VM state was already migrated to
the destination.
2) Once the VM touches a page on the destination that has been excluded
from migration on the source via qemu_guest_free_page_hint() while
postcopy is active, that thread will stall until postcopy finishes
and all threads are woken up. (with older Linux kernels that won't
retry faults when woken up via userfaultfd, we might actually get a
SEGFAULT)
The issue is that the source will refuse to migrate any pages that
are not marked as dirty in the dirty bmap -- for example, because the
page might just have been sent. Consequently, the faulting thread will
stall, waiting for the page to be migrated -- which could take quite
a while and result in guest OS issues.
While we could fix 1) comparatively easily, 2) is harder to get right and
might require more involved RAM migration changes on source and destination
[1].
As it never worked properly, let's not start free page hinting in the
precopy notifier if the postcopy migration capability was enabled to fix
it easily. Capabilities cannot be enabled once migration is already
running.
Note 1: in the future we might either adjust migration code on the source
to track pages that have actually been sent or adjust
migration code on source and destination to eventually send
pages multiple times from the source and and deal with pages
that are sent multiple times on the destination.
Note 2: virtio-mem has similar issues, however, access to "unplugged"
memory by the guest is very rare and we would have to be very
lucky for it to happen during migration. The spec states
"The driver SHOULD NOT read from unplugged memory blocks ..."
and "The driver MUST NOT write to unplugged memory blocks".
virtio-mem will move away from virtio_balloon_free_page_done()
soon and handle this case explicitly on the destination.
[1] https://lkml.kernel.org/r/e79fd18c-aa62-c1d8-c7f3-ba3fc2c25fc8@redhat.com
Fixes: c13c4153f7 ("virtio-balloon: VIRTIO_BALLOON_F_FREE_PAGE_HINT")
Cc: qemu-stable@nongnu.org
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210708095339.20274-2-david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Just a small refactor patch.
vhost_set_backend_type() gets called only in vhost.c, so we can move the
function there and make it static. We can then extern the visibility of
kernel_ops, to match the other VhostOps in vhost-backend.h.
The VhostOps constants now make more sense in vhost.h
Suggested-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Tiberiu Georgescu <tiberiu.georgescu@nutanix.com>
Message-Id: <20210809134015.67941-1-tiberiu.georgescu@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
On vhost-user-blk migration, qemu normally sends a number of commands
to enable logging if VHOST_USER_PROTOCOL_F_LOG_SHMFD is negotiated.
Qemu sends VHOST_USER_SET_FEATURES to enable buffers logging and
VHOST_USER_SET_VRING_ADDR per each started ring to enable "used ring"
data logging.
The issue is that qemu doesn't wait for reply from the vhost daemon
for these commands which may result in races between qemu expectation
of logging starting and actual login starting in vhost daemon.
The race can appear as follows: on migration setup, qemu enables dirty page
logging by sending VHOST_USER_SET_FEATURES. The command doesn't arrive to a
vhost-user-blk daemon immediately and the daemon needs some time to turn the
logging on internally. If qemu doesn't wait for reply, after sending the
command, qemu may start migrateing memory pages to a destination. At this time,
the logging may not be actually turned on in the daemon but some guest pages,
which the daemon is about to write to, may have already been transferred
without logging to the destination. Since the logging wasn't turned on,
those pages won't be transferred again as dirty. So we may end up with
corrupted data on the destination.
The same scenario is applicable for "used ring" data logging, which is
turned on with VHOST_USER_SET_VRING_ADDR command.
To resolve this issue, this patch makes qemu wait for the command result
explicitly if VHOST_USER_PROTOCOL_F_REPLY_ACK is negotiated and logging enabled.
Signed-off-by: Denis Plotnikov <den-plotnikov@yandex-team.ru>
Message-Id: <20210809104824.78830-1-den-plotnikov@yandex-team.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
With the introduction of the batch hinting, meaningless batches can be
created with no IOTLB updates if the memory region was skipped by
vhost_vdpa_listener_skipped_section. This is the case of host notifiers
memory regions, device un/realize, and others. This causes the vdpa
device to receive dma mapping settings with no changes, a possibly
expensive operation for nothing.
To avoid that, VHOST_IOTLB_BATCH_BEGIN hint is delayed until we have a
meaningful (not skipped section) mapping or unmapping operation, and
VHOST_IOTLB_BATCH_END is not written unless at least one of _UPDATE /
_INVALIDATE has been issued.
v3:
* Use a bool instead of a counter avoiding potential number wrapping
* Fix bad check on _commit
* Move VHOST_BACKEND_F_IOTLB_BATCH check to
vhost_vdpa_iotlb_batch_begin_once
v2 (from RFC):
* Rename misleading name
* Abstract start batching function for listener_add/del
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20210812140933.226288-1-eperezma@redhat.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>
vhost_user_backend_init() can fail without setting an error. Unclean.
Its caller vhost_dev_init() compensates by substituting a generic
error then. Goes back to commit 28770ff935 "vhost: Distinguish errors
in vhost_backend_init()".
Clean up by moving the generic error from vhost_dev_init() to all the
failure paths that neglect to set an error.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-14-armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
vhost_user_get_config() can fail without setting an error. Unclean.
Its caller vhost_dev_get_config() compensates by substituting a
generic error then. Goes back to commit 50de51387f "vhost:
Distinguish errors in vhost_dev_get_config()".
Clean up by moving the generic error from vhost_dev_get_config() to
all the failure paths that neglect to set an error.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-13-armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[Sign of error_setg_errno()'s second argument fixed in both calls]
Most callers check the return value. Some check whether it set an
error. Functionally equivalent, but the former tends to be easier on
the eyes, so do that everywhere.
Prior art: commit c6ecec43b2 "qemu-option: Check return value instead
of @err where convenient".
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-10-armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Since commit 9894dc0cdc "char: convert
from GIOChannel to QIOChannel", the first argument to the watch callback
can actually be a QIOChannel, which is not a GIOChannel (but a QEMU
Object).
Even though we never used that pointer, change the callback type to warn
the users. Possibly a better fix later, we may want to store the
callback and call it from intermediary functions.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Block layer patches
- Make blockdev-reopen stable
- Remove deprecated qemu-img backing file without format
- rbd: Convert to coroutines and add write zeroes support
- rbd: Updated MAINTAINERS
- export/fuse: Allow other users access to the export
- vhost-user: Fix backends without multiqueue support
- Fix drive-backup transaction endless drained section
# gpg: Signature made Fri 09 Jul 2021 13:49:22 BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74 56FE 7F09 B272 C88F 2FD6
* remotes/kevin/tags/for-upstream: (28 commits)
block: Make blockdev-reopen stable API
iotests: Test reopening multiple devices at the same time
block: Support multiple reopening with x-blockdev-reopen
block: Acquire AioContexts during bdrv_reopen_multiple()
block: Add bdrv_reopen_queue_free()
qcow2: Fix dangling pointer after reopen for 'file'
qemu-img: Improve error for rebase without backing format
qemu-img: Require -F with -b backing image
qcow2: Prohibit backing file changes in 'qemu-img amend'
blockdev: fix drive-backup transaction endless drained section
vhost-user: Fix backends without multiqueue support
MAINTAINERS: add block/rbd.c reviewer
block/rbd: fix type of task->complete
iotests/fuse-allow-other: Test allow-other
iotests/308: Test +w on read-only FUSE exports
export/fuse: Let permissions be adjustable
export/fuse: Give SET_ATTR_SIZE its own branch
export/fuse: Add allow-other option
export/fuse: Pass default_permissions for mount
util/uri: do not check argument of uri_free()
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Machine queue, 2021-07-07
Deprecation:
* Deprecate pmem=on with non-DAX capable backend file
(Igor Mammedov)
Feature:
* virtio-mem: vfio support (David Hildenbrand)
Cleanup:
* vmbus: Don't make QOM property registration conditional
(Eduardo Habkost)
# gpg: Signature made Thu 08 Jul 2021 20:55:04 BST
# gpg: using RSA key 5A322FD5ABC4D3DBACCFD1AA2807936F984DC5A6
# gpg: issuer "ehabkost@redhat.com"
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>" [full]
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF D1AA 2807 936F 984D C5A6
* remotes/ehabkost-gl/tags/machine-next-pull-request:
vfio: Disable only uncoordinated discards for VFIO_TYPE1 iommus
virtio-mem: Require only coordinated discards
softmmu/physmem: Extend ram_block_discard_(require|disable) by two discard types
softmmu/physmem: Don't use atomic operations in ram_block_discard_(disable|require)
vfio: Support for RamDiscardManager in the vIOMMU case
vfio: Sanity check maximum number of DMA mappings with RamDiscardManager
vfio: Query and store the maximum number of possible DMA mappings
vfio: Support for RamDiscardManager in the !vIOMMU case
virtio-mem: Implement RamDiscardManager interface
virtio-mem: Don't report errors when ram_block_discard_range() fails
virtio-mem: Factor out traversing unplugged ranges
memory: Helpers to copy/free a MemoryRegionSection
memory: Introduce RamDiscardManager for RAM memory regions
Deprecate pmem=on with non-DAX capable backend file
vmbus: Don't make QOM property registration conditional
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
dev->max_queues was never initialised for backends that don't support
VHOST_USER_PROTOCOL_F_MQ, so it would use 0 as the maximum number of
queues to check against and consequently fail for any such backend.
Set it to 1 if the backend doesn't have multiqueue support.
Fixes: c90bd505a3
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210705171429.29286-1-kwolf@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vIOMMU support works already with RamDiscardManager as long as guests only
map populated memory. Both, populated and discarded memory is mapped
into &address_space_memory, where vfio_get_xlat_addr() will find that
memory, to create the vfio mapping.
Sane guests will never map discarded memory (e.g., unplugged memory
blocks in virtio-mem) into an IOMMU - or keep it mapped into an IOMMU while
memory is getting discarded. However, there are two cases where a malicious
guests could trigger pinning of more memory than intended.
One case is easy to handle: the guest trying to map discarded memory
into an IOMMU.
The other case is harder to handle: the guest keeping memory mapped in
the IOMMU while it is getting discarded. We would have to walk over all
mappings when discarding memory and identify if any mapping would be a
violation. Let's keep it simple for now and print a warning, indicating
that setting RLIMIT_MEMLOCK can mitigate such attacks.
We have to take care of incoming migration: at the point the
IOMMUs get restored and start creating mappings in vfio, RamDiscardManager
implementations might not be back up and running yet: let's add runstate
priorities to enforce the order when restoring.
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Auger Eric <eric.auger@redhat.com>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Cc: teawater <teawaterz@linux.alibaba.com>
Cc: Marek Kedzierski <mkedzier@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210413095531.25603-10-david@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Now, if virtio device is not present on virtio-bus - pci config callbacks
will not lead to possible crush. The read will return "-1" which should be
interpreted by a driver that pci device may be unplugged.
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Message-Id: <20210609095843.141378-3-andrew@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
During unplug the virtio device is unplugged from virtio-bus on pci. In some cases,
requests to virtio-pci mm may acquire during/after unplug. Added check that virtio
device is on the bus, for "common" memory region.
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Message-Id: <20210609095843.141378-2-andrew@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@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>
virtio devices support separate iothreads waiting for
events from file descriptors. These are asynchronous
events that can't be recorded and replayed, therefore
this patch disables ioeventfd for all devices when
record or replay is enabled.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Message-Id: <162125678869.1252810.4317416444097392406.stgit@pasha-ThinkPad-X280>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Instead of just returning 0/-1 and letting the caller make up a
meaningless error message, add an Error parameter to allow reporting the
real error and switch to 0/-errno so that different kind of errors can
be distinguished in the caller.
config_len in vhost_user_get_config() is defined by the device, so if
it's larger than VHOST_USER_MAX_CONFIG_SIZE, this is a programming
error. Turn the corresponding check into an assertion.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210609154658.350308-6-kwolf@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Instead of just returning 0/-1 and letting the caller make up a
meaningless error message, switch to 0/-errno so that different kinds of
errors can be distinguished in the caller.
This involves changing a few more callbacks in VhostOps to return
0/-errno: .vhost_set_owner(), .vhost_get_features() and
.vhost_virtqueue_set_busyloop_timeout(). The implementations of these
functions are trivial as they generally just send a message to the
backend.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210609154658.350308-4-kwolf@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
