At some point, after unplugging virtio-pci the virtio device may be unrealised,
but the memory regions may be present in flatview. So, it's a possible situation
when memory region's callbacks are called for "unplugged" device.
Previous two patches made sure this case does not cause QEMU to crash.
This patch adds check for "notify" memory region. Now reads will return "-1" if a virtio
device is not present on a virtio bus.
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1938042
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1743098
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
Message-Id: <20210609095843.141378-4-andrew@daynix.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
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>
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>
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.
Specifically, in vhost-user, EPROTO is used for all errors that relate
to the connection itself, whereas other error codes are used for errors
relating to the content of the connection. This will allow us later to
automatically reconnect when the connection goes away, without ending up
in an endless loop if it's a permanent error in the configuration.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210609154658.350308-3-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>
This allows callers to return better error messages instead of making
one up while the real error ends up on stderr. Most callers can
immediately make use of this because they already have an Error
parameter themselves. The others just keep printing the error with
error_report_err().
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20210609154658.350308-2-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>
We used to initialize backend_features during vhost_vdpa_init()
regardless whether or not it was supported by vhost. This will lead
the unsupported features like VIRTIO_F_IN_ORDER to be included and set
to the vhost-vdpa during vhost_dev_start. Because the
VIRTIO_F_IN_ORDER is not supported by vhost-vdpa so it won't be
advertised to guest which will break the datapath.
Fix this by not initializing the backend_features, so the
acked_features could be built only from guest features via
vhost_net_ack_features().
Fixes: 108a64818e ("vhost-vdpa: introduce vhost-vdpa backend")
Cc: qemu-stable@nongnu.org
Cc: Gautam Dawar <gdawar@xilinx.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
This patch implements the vq notification mapping support for
vhost-vDPA. This is simply done by using mmap()/munmap() for the
vhost-vDPA fd during device start/stop. For the device without
notification mapping support, we fall back to eventfd based
notification gracefully.
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
vDPA is not tie to any specific hardware, for safety and simplicity,
vhost-vDPA doesn't allow MMIO area to be mapped via IOTLB. Only the
doorbell could be mapped via mmap(). So this patch exclude skip the
ram device from the IOTLB mapping.
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The symbol address_space_memory are already declared in
include/exec/address-spaces.h. So let's add this header file
and remove the redundant declaration in include/hw/virtio/vhost-vdpa.h.
Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20210517123246.999-1-xieyongji@bytedance.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Commit e50caf4a5c ("tracing: convert documentation to rST")
converted docs/devel/tracing.txt to docs/devel/tracing.rst.
We still have several references to the old file, so let's fix them
with the following command:
sed -i s/tracing.txt/tracing.rst/ $(git grep -l docs/devel/tracing.txt)
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210517151702.109066-2-sgarzare@redhat.com>
Signed-off-by: Thomas Huth <thuth@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>
Creating a device with a number of queues that isn't supported by the
backend is pointless, the device won't work properly and the error
messages are rather confusing.
Just fail to create the device if num-queues is higher than what the
backend supports.
Since the relationship between num-queues and the number of virtqueues
depends on the specific device, this is an additional value that needs
to be initialised by the device. For convenience, allow leaving it 0 if
the check should be skipped. This makes sense for vhost-user-net where
separate vhost devices are used for the queues and custom initialisation
code is needed to perform the check.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1935031
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20210429171316.162022-7-kwolf@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit 2943b53f6 (' virtio: force VIRTIO_F_IOMMU_PLATFORM') made sure
that vhost can't just reject VIRTIO_F_IOMMU_PLATFORM when it was
requested. However, just adding it back to the negotiated flags isn't
right either because it promises support to the guest that the device
actually doesn't support. One example of a vhost-user device that
doesn't have support for the flag is the vhost-user-blk export of QEMU.
Instead of successfully creating a device that doesn't work, just fail
to plug the device when it doesn't support the feature, but it was
requested. This results in much clearer error messages.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1935019
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20210429171316.162022-6-kwolf@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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
As it's only used inside hw/virtio/vhost-vdpa.c.
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Message-Id: <20210413133737.1574-1-yuzenghui@huawei.com>
Reviewed-by: Stefano Garzarella <sgarzare@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>
This patch adds ioeventfd flag for virtio-mmio configuration.
It allows switching ioeventfd on and off.
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>
Message-Id: <161700379211.1135943.8859209566937991305.stgit@pasha-ThinkPad-X280>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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>
The bulk stage is kind of weird: migration_bitmap_find_dirty() will
indicate a dirty page, however, ram_save_host_page() will never save it, as
migration_bitmap_clear_dirty() detects that it is not dirty.
We already fill the bitmap in ram_list_init_bitmaps() with ones, marking
everything dirty - it didn't used to be that way, which is why we needed
an explicit first bulk stage.
Let's simplify: make the bitmap the single source of thuth. Explicitly
handle the "xbzrle_enabled after first round" case.
Regarding XBZRLE (implicitly handled via "ram_bulk_stage = false" right
now), there is now a slight change in behavior:
- Colo: When starting, it will be disabled (was implicitly enabled)
until the first round actually finishes.
- Free page hinting: When starting, XBZRLE will be disabled (was implicitly
enabled) until the first round actually finished.
- Snapshots: When starting, XBZRLE will be disabled. We essentially only
do a single run, so I guess it will never actually get disabled.
Postcopy seems to indirectly disable it in ram_save_page(), so there
shouldn't be really any change.
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210216105039.40680-1-david@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@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>
Make virtio-fs take into account server capabilities.
Just returning requested features assumes they all of then are implemented
by server and results in setting unsupported configuration if some of them
are absent.
Signed-off-by: Anton Kuchin <antonkuchin@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
With changes suggested by Stefan
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The same thing as for incoming postcopy - we cannot deal with concurrent
RAM discards when using background snapshot feature in outgoing migration.
Fixes: 8518278a6a (migration: implementation
of background snapshot thread)
Signed-off-by: Andrey Gruzdev <andrey.gruzdev@virtuozzo.com>
Reported-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Message-Id: <20210401092226.102804-3-andrey.gruzdev@virtuozzo.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Commit 4c70875372 ("pci: advertise a page aligned ATS") advertises
the page aligned via ATS capability (RO) to unbrek recent Linux IOMMU
drivers since 5.2. But it forgot the compat the capability which
breaks the migration from old machine type:
(qemu) qemu-kvm: get_pci_config_device: Bad config data: i=0x104 read:
0 device: 20 cmask: ff wmask: 0 w1cmask:0
This patch introduces a new parameter "x-ats-page-aligned" for
virtio-pci device and turns it on for machine type which is newer than
5.1.
Cc: Michael S. Tsirkin <mst@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: qemu-stable@nongnu.org
Fixes: 4c70875372 ("pci: advertise a page aligned ATS")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20210406040330.11306-1-jasowang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The value is assigned later in this procedure.
Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Message-Id: <20210315115937.14286-3-yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1743098
This commit completes the solution of segfault in hot unplug flow
(by commit ccec7e9603).
Added missing check for vdev in virtio_pci_isr_read.
Typical stack of crash:
virtio_pci_isr_read ../hw/virtio/virtio-pci.c:1365 with proxy-vdev = 0
memory_region_read_accessor at ../softmmu/memory.c:442
access_with_adjusted_size at ../softmmu/memory.c:552
memory_region_dispatch_read1 at ../softmmu/memory.c:1420
memory_region_dispatch_read at ../softmmu/memory.c:1449
flatview_read_continue at ../softmmu/physmem.c:2822
flatview_read at ../softmmu/physmem.c:2862
address_space_read_full at ../softmmu/physmem.c:2875
Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Message-Id: <20210315115937.14286-2-yuri.benditovich@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
ret in virtio_pmem_resp is a uint32_t variable, which should be assigned
using virtio_stl_p.
The kernel side driver does not guarantee virtio_pmem_resp to be initialized
to zero in advance, So sometimes the flush operation will fail.
Signed-off-by: Wang Liang <wangliangzz@inspur.com>
Message-Id: <20210317024145.271212-1-wangliangzz@126.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now that everything is in place, have the nested event loop to monitor
the slave channel. The source in the main event loop is destroyed and
recreated to ensure any pending even for the slave channel that was
previously detected is purged. This guarantees that the main loop
wont invoke slave_read() based on an event that was already handled
by the nested loop.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-7-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
A deadlock condition potentially exists if a vhost-user process needs
to request something to QEMU on the slave channel while processing a
vhost-user message.
This doesn't seem to affect any vhost-user implementation so far, but
this is currently biting the upcoming enablement of DAX with virtio-fs.
The issue is being observed when the guest does an emergency reboot while
a mapping still exits in the DAX window, which is very easy to get with
a busy enough workload (e.g. as simulated by blogbench [1]) :
- QEMU sends VHOST_USER_GET_VRING_BASE to virtiofsd.
- In order to complete the request, virtiofsd then asks QEMU to remove
the mapping on the slave channel.
All these dialogs are synchronous, hence the deadlock.
As pointed out by Stefan Hajnoczi:
When QEMU's vhost-user master implementation sends a vhost-user protocol
message, vhost_user_read() does a "blocking" read during which slave_fd
is not monitored by QEMU.
The natural solution for this issue is an event loop. The main event
loop cannot be nested though since we have no guarantees that its
fd handlers are prepared for re-entrancy.
Introduce a new event loop that only monitors the chardev I/O for now
in vhost_user_read() and push the actual reading to a one-shot handler.
A subsequent patch will teach the loop to monitor and process messages
from the slave channel as well.
[1] https://github.com/jedisct1/Blogbench
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-6-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
The slave channel is implemented with socketpair() : QEMU creates
the pair, passes one of the socket to virtiofsd and monitors the
other one with the main event loop using qemu_set_fd_handler().
In order to fix a potential deadlock between QEMU and a vhost-user
external process (e.g. virtiofsd with DAX), we want to be able to
monitor and service the slave channel while handling vhost-user
requests.
Prepare ground for this by converting the slave channel to be a
QIOChannelSocket. This will make monitoring of the slave channel
as simple as calling qio_channel_add_watch_source(). Since the
connection is already established between the two sockets, only
incoming I/O (G_IO_IN) and disconnect (G_IO_HUP) need to be
serviced.
This also allows to get rid of the ancillary data parsing since
QIOChannelSocket can do this for us. Note that the MSG_CTRUNC
check is dropped on the way because QIOChannelSocket ignores this
case. This isn't a problem since slave_read() provisions space for
8 file descriptors, but affected vhost-user slave protocol messages
generally only convey one. If for some reason a buggy implementation
passes more file descriptors, no need to break the connection, just
like we don't break it if some other type of ancillary data is
received : this isn't explicitely violating the protocol per-se so
it seems better to ignore it.
The current code errors out on short reads and writes. Use the
qio_channel_*_all() variants to address this on the way.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-5-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-4-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Some message types, e.g. VHOST_USER_SLAVE_VRING_HOST_NOTIFIER_MSG,
can convey file descriptors. These must be closed before returning
from slave_read() to avoid being leaked. This can currently be done
in two different places:
[1] just after the request has been processed
[2] on the error path, under the goto label err:
These path are supposed to be mutually exclusive but they are not
actually. If the VHOST_USER_NEED_REPLY_MASK flag was passed and the
sending of the reply fails, both [1] and [2] are performed with the
same descriptor values. This can potentially cause subtle bugs if one
of the descriptor was recycled by some other thread in the meantime.
This code duplication complicates rollback for no real good benefit.
Do the closing in a unique place, under a new fdcleanup: goto label
at the end of the function.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-3-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
slave_read() checks EAGAIN when reading or writing to the socket
fails. This gives the impression that the slave channel is in
non-blocking mode, which is certainly not the case with the current
code base. And the rest of the code isn't actually ready to cope
with non-blocking I/O.
Just drop the checks everywhere in this function for the sake of
clarity.
Signed-off-by: Greg Kurz <groug@kaod.org>
Message-Id: <20210312092212.782255-2-groug@kaod.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Both functions don't check the personality of the interface (legacy or
modern) before accessing the configuration memory and always use
virtio_config_readX()/virtio_config_writeX().
With this patch, they now check the personality and in legacy mode
call virtio_config_readX()/virtio_config_writeX(), otherwise call
virtio_config_modern_readX()/virtio_config_modern_writeX().
This change has been tested with virtio-mmio guests (virt stretch/armhf and
virt sid/m68k) and virtio-pci guests (pseries RHEL-7.3/ppc64 and /ppc64le).
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20210314200300.3259170-1-laurent@vivier.eu>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Currently, the default msix vectors for virtio-net-pci is 3 which is
obvious not suitable for multiqueue guest, so we depends on the user
or management tools to pass a correct vectors parameter. In fact, we
can simplifying this by calculating the number of vectors on realize.
Consider we have N queues, the number of vectors needed is 2*N + 2
(#queue pairs + plus one config interrupt and control vq). We didn't
check whether or not host support control vq because it was added
unconditionally by qemu to avoid breaking legacy guests such as Minix.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
Unmap notifiers work with an address mask assuming an
invalidation range of a power of 2. Nothing mandates this
in the VIRTIO-IOMMU spec.
So in case the range is not a power of 2, split it into
several invalidations.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-id: 20210309102742.30442-4-eric.auger@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
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>
An assorted set of spelling fixes in various places.
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <20210309111510.79495-1-mjt@msgid.tls.msk.ru>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
At the moment the following QEMU command line triggers an assertion
failure On xlnx-versal SOC:
qemu-system-aarch64 \
-machine xlnx-versal-virt -nographic -smp 2 -m 128 \
-fsdev local,id=shareid,path=${HOME}/work,security_model=none \
-device virtio-9p-device,fsdev=shareid,mount_tag=share \
-fsdev local,id=shareid1,path=${HOME}/Music,security_model=none \
-device virtio-9p-device,fsdev=shareid1,mount_tag=share1
qemu-system-aarch64: ../migration/savevm.c:860:
vmstate_register_with_alias_id:
Assertion `!se->compat || se->instance_id == 0' failed.
This problem was fixed on arm virt platform in commit f58b39d2d5
("virtio-mmio: format transport base address in BusClass.get_dev_path")
It works perfectly on arm virt platform. but there is still there on
xlnx-versal SOC.
The main difference between arm virt and xlnx-versal is they use
different way to create virtio-mmio qdev. on arm virt, it calls
sysbus_create_simple("virtio-mmio", base, pic[irq]); which will call
sysbus_mmio_map internally and assign base address to subsys device
mmio correctly. but xlnx-versal's implements won't do this.
However, xlnx-versal can't switch to sysbus_create_simple() to create
virtio-mmio device. It's because xlnx-versal's cpu use
VersalVirt.soc.fpd.apu.mr as it's memory. which is subregion of
system_memory. sysbus_create_simple will add virtio to system_memory,
which can't be accessed by cpu.
Besides, xlnx-versal can't add sysbus_mmio_map api call too, because
this will add memory region to system_memory, and it can't be added
to VersalVirt.soc.fpd.apu.mr again.
We can solve this by assign correct base address offset on dev_path.
This path was test on aarch64 virt & xlnx-versal platform.
Signed-off-by: schspa <schspa@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Requiring a conditional for every goto is tedious:
if (busyloop_timeout) {
goto fail_busyloop;
} else {
goto fail;
}
Move the conditional to into the fail_busyloop label so that it's safe
to jump to this label unconditionally.
This change makes the migrate_add_blocker() error case more consistent.
It jumped to fail_busyloop unconditionally whereas the memslots limits
error case was conditional.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20210222114931.272308-1-stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@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>
The category of the virtio-pmem device is not set, put it into the 'storage'
category.
Signed-off-by: Gan Qixin <ganqixin@huawei.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@cloud.ionos.com>
Message-Id: <20201130083630.2520597-3-ganqixin@huawei.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
When viewing/debugging memory regions it is sometimes hard to figure
out which PCI device something belongs to. Make the names unique by
including the vdev name in the name string.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20210213130325.14781-2-alex.bennee@linaro.org>
Not checking this can lead to invalid dev->vdev member access in
vhost_device_iotlb_miss if backend issue an iotlb message in a bad
timing, either maliciously or by a bug.
Reproduced rebooting a guest with testpmd in txonly forward mode.
#0 0x0000559ffff94394 in vhost_device_iotlb_miss (
dev=dev@entry=0x55a0012f6680, iova=10245279744, write=1)
at ../hw/virtio/vhost.c:1013
#1 0x0000559ffff9ac31 in vhost_backend_handle_iotlb_msg (
imsg=0x7ffddcfd32c0, dev=0x55a0012f6680)
at ../hw/virtio/vhost-backend.c:411
#2 vhost_backend_handle_iotlb_msg (dev=dev@entry=0x55a0012f6680,
imsg=imsg@entry=0x7ffddcfd32c0)
at ../hw/virtio/vhost-backend.c:404
#3 0x0000559fffeded7b in slave_read (opaque=0x55a0012f6680)
at ../hw/virtio/vhost-user.c:1464
#4 0x000055a0000c541b in aio_dispatch_handler (
ctx=ctx@entry=0x55a0010a2120, node=0x55a0012d9e00)
at ../util/aio-posix.c:329
Fixes: 020e571b8b ("vhost: rework IOTLB messaging")
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20210129090728.831208-1-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>
This property was only required for compatibility reasons in the
pc-1.0 machine type and earlier. Now that these machine types have
been removed, the property is not useful anymore.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210203171832.483176-4-thuth@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: David Hildenbrand <david@redhat.com>
Previous work on dev-iotlb message broke vhost on either SMMU or virtio-iommu
since dev-iotlb (or PCIe ATS) is not yet supported for those archs.
An initial idea is that we can let IOMMU to export this information to vhost so
that vhost would know whether the vIOMMU would support dev-iotlb, then vhost
can conditionally register to dev-iotlb or the old iotlb way. We can work
based on some previous patch to introduce PCIIOMMUOps as Yi Liu proposed [1].
However it's not as easy as I thought since vhost_iommu_region_add() does not
have a PCIDevice context at all since it's completely a backend. It seems
non-trivial to pass over a PCI device to the backend during init. E.g. when
the IOMMU notifier registered hdev->vdev is still NULL.
To make the fix smaller and easier, this patch goes the other way to leverage
the flag_changed() hook of vIOMMUs so that SMMU and virtio-iommu can trap the
dev-iotlb registration and fail it. Then vhost could try the fallback solution
as using UNMAP invalidation for it's translations.
[1] https://lore.kernel.org/qemu-devel/1599735398-6829-4-git-send-email-yi.l.liu@intel.com/
Reported-by: Eric Auger <eric.auger@redhat.com>
Fixes: b68ba1ca57
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20210204191228.187550-1-peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This patch adds trace events for virtio-pmem functionality.
Adding trace events for virtio pmem request, reponse and host
side fsync functionality.
Signed-off-by: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Message-Id: <20201117115705.32195-1-pankaj.gupta.linux@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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>
In the kernel, virtio_gpu_init() uses virtio_get_shm_region()
since
commit 6076a9711dc5 ("drm/virtio: implement blob resources: probe for host visible region")
but vm_get_shm_region() unconditionally uses VIRTIO_MMIO_SHM_SEL to
get the address and the length of the region.
commit 38e895487afc ("virtio: Implement get_shm_region for MMIO transport"
As this is not implemented in QEMU, address and length are 0 and passed
as is to devm_request_mem_region() that triggers a crash:
[drm:virtio_gpu_init] *ERROR* Could not reserve host visible region
Unable to handle kernel NULL pointer dereference at virtual address (ptrval)
According to the comments in the kernel, a non existent shared region
has a length of (u64)-1.
This is what we return now with this patch to disable the region.
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Message-Id: <20201220163539.2255963-1-laurent@vivier.eu>
Acked-by: Gerd Hoffmann <kraxel@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>