Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the memory listener to a common place rather than always in the
first / last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-14-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The memory listener functions can call these too. Make vdpa_iommu work
with VhostVDPAShared.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-13-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The callers only have the shared information by the end of this series.
Start converting this functions.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-12-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the iommu_list member to VhostVDPAShared so all vhost_vdpa can use
it, rather than always in the first / last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-11-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
It is always VHOST_IOTLB_MSG_V2. We can always make it back per
vhost_dev if needed.
This change makes easier for vhost_vdpa_map and unmap not to depend on
vhost_vdpa but only in VhostVDPAShared.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-10-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the backend_cap member to VhostVDPAShared so all vhost_vdpa can use
it, rather than always in the first / last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-9-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the iotlb_batch_begin_sent member to VhostVDPAShared so all
vhost_vdpa can use it, rather than always in the first / last
vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-8-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the file descriptor to VhostVDPAShared so all vhost_vdpa can use
it, rather than always in the first / last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-7-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
By the end of this series dma_map and dma_unmap functions don't have the
vdpa device for tracing. Movinge trace function to shared member one.
Print it also in the vdpa initialization so log reader can relate them.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-6-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the shadow_data member to VhostVDPAShared so all vhost_vdpa can use
it, rather than always in the first or last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-5-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the iova range to VhostVDPAShared so all vhost_vdpa can use it,
rather than always in the first or last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-4-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next patches will register the vhost_vdpa memory listener while the VM
is migrating at the destination, so we can map the memory to the device
before stopping the VM at the source. The main goal is to reduce the
downtime.
However, the destination QEMU is unaware of which vhost_vdpa device will
register its memory_listener. If the source guest has CVQ enabled, it
will be the CVQ device. Otherwise, it will be the first one.
Move the iova tree to VhostVDPAShared so all vhost_vdpa can use it,
rather than always in the first or last vhost_vdpa.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20231221174322.3130442-3-eperezma@redhat.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Next commits will set DRIVER and ACKNOWLEDGE flags repeatedly in the
case of a migration destination. Let's save ioctls with this.
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231215172830.2540987-2-eperezma@redhat.com>
This adds the vhost backend callouts for the worker ioctls added in the
6.4 linux kernel commit:
c1ecd8e95007 ("vhost: allow userspace to create workers")
Signed-off-by: Mike Christie <michael.christie@oracle.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20231204231618.21962-2-michael.christie@oracle.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>
Since the driver doesn't support interrupts, we must return early when
index is set to VIRTIO_CONFIG_IRQ_IDX. Basically the same thing Viresh
did for "91208dd297f2 virtio: i2c: Check notifier helpers for
VIRTIO_CONFIG_IRQ_IDX".
Fixes: 544f0278af ("virtio: introduce macro VIRTIO_CONFIG_IRQ_IDX")
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Message-Id: <20231025171841.3379663-1-mathieu.poirier@linaro.org>
Tested-by: Leo Yan <leo.yan@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Keep it the same to vhost-user-blk.
At the same time, fix the vhost_reset_device.
Signed-off-by: Li Feng <fengli@smartx.com>
Message-Id: <20231123055431.217792-3-fengli@smartx.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>
If the error occurs in vhost_dev_init, the value of s->connected is set to true
in advance, and there is no chance to enter this function execution again
in the future.
Signed-off-by: Li Feng <fengli@smartx.com>
Message-Id: <20231123055431.217792-2-fengli@smartx.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>
The code already checks iommu_mr is not NULL so there is no
need to check container_of() is not NULL. Remove the check.
Fixes: CID 1523901
Fixes: 09b4c3d6a2 ("virtio-iommu: Record whether a probe request has
been issued")
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reported-by: Coverity (CID 1523901)
Message-Id: <20231109170715.259520-1-eric.auger@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Commit 0be6bfac62 ("qdev: Implement variable length array properties")
added the DEFINE_PROP_ARRAY() macro with the following comment:
* It is the responsibility of the device deinit code to free the
* @_arrayfield memory.
Commit 8077b8e549 added:
DEFINE_PROP_ARRAY("reserved-regions", VirtIOIOMMUPCI,
vdev.nb_reserved_regions, vdev.reserved_regions,
qdev_prop_reserved_region, ReservedRegion),
but forgot to free the 'vdev.reserved_regions' array. Do it in the
instance_finalize() handler.
Cc: qemu-stable@nongnu.org
Fixes: 8077b8e549 ("virtio-iommu-pci: Add array of Interval properties") # v5.1.0+
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Message-id: 20231121174051.63038-3-philmd@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The VirtioPCIDeviceTypeInfo structure, added in commit a4ee4c8baa
("virtio: Helper for registering virtio device types") got extended
in commit 8ea90ee690 ("virtio: add class_size") with the @class_size
field. Do similarly with the @instance_finalize field.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20231121174051.63038-2-philmd@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
When running with "dynamic-memslots=off", we enter
virtio_mem_activate_memslots_to_plug() to return immediately again
because "vmem->dynamic_memslots == false". However, the compiler might
not optimize out calculating start_idx+end_idx, where we divide by
vmem->memslot_size. In such a configuration, the memslot size is 0 and
we'll get a division by zero:
(qemu) qom-set vmem0 requested-size 3G
(qemu) q35.sh: line 38: 622940 Floating point exception(core dumped)
The same is true for virtio_mem_deactivate_unplugged_memslots(), however
we never really reach that code without a prior
virtio_mem_activate_memslots_to_plug() call.
Let's fix it by simply calling these functions only with
"dynamic-memslots=on".
This was found when using a debug build of QEMU.
Message-ID: <20231023111341.219317-1-david@redhat.com>
Reprted-by: Mario Casquero <mcasquer@redhat.com>
Fixes: 177f9b1ee4 ("virtio-mem: Expose device memory dynamically via multiple memslots if enabled")
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
virtio sound card support
vhost-user: back-end state migration
cxl:
line length reduction
enabling fabric management
vhost-vdpa:
shadow virtqueue hash calculation Support
shadow virtqueue RSS Support
tests:
CPU topology related smbios test cases
Fixes, cleanups all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEXQn9CHHI+FuUyooNKB8NuNKNVGkFAmVKDDoPHG1zdEByZWRo
YXQuY29tAAoJECgfDbjSjVRpF08H/0Zts8uvkHbgiOEJw4JMHU6/VaCipfIYsp01
GSfwYOyEsXJ7GIxKWaCiMnWXEm7tebNCPKf3DoUtcAojQj3vuF9XbWBKw/bfRn83
nGO/iiwbYViSKxkwqUI+Up5YiN9o0M8gBFrY0kScPezbnYmo5u2bcADdEEq6gH68
D0Ea8i+WmszL891ypvgCDBL2ObDk3qX3vA5Q6J2I+HKX2ofJM59BwaKwS5ghw+IG
BmbKXUZJNjUQfN9dQ7vJuiuqdknJ2xUzwW2Vn612ffarbOZB1DZ6ruWlrHty5TjX
0w4IXEJPBgZYbX9oc6zvTQnbLDBJbDU89mnme0TcmNMKWmQKTtc=
=vEv+
-----END PGP SIGNATURE-----
Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging
virtio,pc,pci: features, fixes
virtio sound card support
vhost-user: back-end state migration
cxl:
line length reduction
enabling fabric management
vhost-vdpa:
shadow virtqueue hash calculation Support
shadow virtqueue RSS Support
tests:
CPU topology related smbios test cases
Fixes, cleanups all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# -----BEGIN PGP SIGNATURE-----
#
# iQFDBAABCAAtFiEEXQn9CHHI+FuUyooNKB8NuNKNVGkFAmVKDDoPHG1zdEByZWRo
# YXQuY29tAAoJECgfDbjSjVRpF08H/0Zts8uvkHbgiOEJw4JMHU6/VaCipfIYsp01
# GSfwYOyEsXJ7GIxKWaCiMnWXEm7tebNCPKf3DoUtcAojQj3vuF9XbWBKw/bfRn83
# nGO/iiwbYViSKxkwqUI+Up5YiN9o0M8gBFrY0kScPezbnYmo5u2bcADdEEq6gH68
# D0Ea8i+WmszL891ypvgCDBL2ObDk3qX3vA5Q6J2I+HKX2ofJM59BwaKwS5ghw+IG
# BmbKXUZJNjUQfN9dQ7vJuiuqdknJ2xUzwW2Vn612ffarbOZB1DZ6ruWlrHty5TjX
# 0w4IXEJPBgZYbX9oc6zvTQnbLDBJbDU89mnme0TcmNMKWmQKTtc=
# =vEv+
# -----END PGP SIGNATURE-----
# gpg: Signature made Tue 07 Nov 2023 18:06:50 HKT
# 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
* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (63 commits)
acpi/tests/avocado/bits: enable console logging from bits VM
acpi/tests/avocado/bits: enforce 32-bit SMBIOS entry point
hw/cxl: Add tunneled command support to mailbox for switch cci.
hw/cxl: Add dummy security state get
hw/cxl/type3: Cleanup multiple CXL_TYPE3() calls in read/write functions
hw/cxl/mbox: Add Get Background Operation Status Command
hw/cxl: Add support for device sanitation
hw/cxl/mbox: Wire up interrupts for background completion
hw/cxl/mbox: Add support for background operations
hw/cxl: Implement Physical Ports status retrieval
hw/pci-bridge/cxl_downstream: Set default link width and link speed
hw/cxl/mbox: Add Physical Switch Identify command.
hw/cxl/mbox: Add Information and Status / Identify command
hw/cxl: Add a switch mailbox CCI function
hw/pci-bridge/cxl_upstream: Move defintion of device to header.
hw/cxl/mbox: Generalize the CCI command processing
hw/cxl/mbox: Pull the CCI definition out of the CXLDeviceState
hw/cxl/mbox: Split mailbox command payload into separate input and output
hw/cxl/mbox: Pull the payload out of struct cxl_cmd and make instances constant
hw/cxl: Fix a QEMU_BUILD_BUG_ON() in switch statement scope issue.
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
A virtio-fs device's VM state consists of:
- the virtio device (vring) state (VMSTATE_VIRTIO_DEVICE)
- the back-end's (virtiofsd's) internal state
We get/set the latter via the new vhost operations to transfer migratory
state. It is its own dedicated subsection, so that for external
migration, it can be disabled.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20231016134243.68248-8-hreitz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost_save_backend_state() and vhost_load_backend_state() can be used by
vhost front-ends to easily save and load the back-end's state to/from
the migration stream.
Because we do not know the full state size ahead of time,
vhost_save_backend_state() simply reads the data in 1 MB chunks, and
writes each chunk consecutively into the migration stream, prefixed by
its length. EOF is indicated by a 0-length chunk.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20231016134243.68248-7-hreitz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Add the interface for transferring the back-end's state during migration
as defined previously in vhost-user.rst.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-Id: <20231016134243.68248-6-hreitz@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
* Support for non 64b IOVA space
* Introduction of a PCIIOMMUOps callback structure to ease future
extensions
* Fix for a buffer overrun when writing the VF token
* PPC cleanups preparing ground for IOMMUFD support
-----BEGIN PGP SIGNATURE-----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=/Du0
-----END PGP SIGNATURE-----
Merge tag 'pull-vfio-20231106' of https://github.com/legoater/qemu into staging
vfio queue:
* Support for non 64b IOVA space
* Introduction of a PCIIOMMUOps callback structure to ease future
extensions
* Fix for a buffer overrun when writing the VF token
* PPC cleanups preparing ground for IOMMUFD support
# -----BEGIN PGP SIGNATURE-----
#
# iQIzBAABCAAdFiEEoPZlSPBIlev+awtgUaNDx8/77KEFAmVI+bIACgkQUaNDx8/7
# 7KHW4g/9FmgX0k2Elm1BAul3slJtuBT8/iHKfK19rhXICxhxS5xBWJA8FmosTWAT
# 91YqQJhOHARxLd9VROfv8Fq8sAo+Ys8bP3PTXh5satjY5gR9YtmMSVqvsAVLn7lv
# a/0xp7wPJt2UeKzvRNUqFXNr7yHPwxFxbJbmmAJbNte8p+TfE2qvojbJnu7BjJbg
# sTtS/vFWNJwtuNYTkMRoiZaUKEoEZ8LnslOqKUjgeO59g4i3Dq8e2JCmHANPFWUK
# cWmr7AqcXgXEnLSDWTtfN53bjcSCYkFVb4WV4Wv1/7hUF5jQ4UR0l3B64xWe0M3/
# Prak3bWOM/o7JwLBsgaWPngXA9V0WFBTXVF4x5qTwhuR1sSV8MxUvTKxI+qqiEzA
# FjU89oSZ+zXId/hEUuTL6vn1Th8/6mwD0L9ORchNOQUKzCjBzI4MVPB09nM3AdPC
# LGThlufsZktdoU2KjMHpc+gMIXQYsxkgvm07K5iZTZ5eJ4tV5KB0aPvTZppGUxe1
# YY9og9F3hxjDHQtEuSY2rzBQI7nrUpd1ZI5ut/3ZgDWkqD6aGRtMme4n4GsGsYb2
# Ht9+d2RL9S8uPUh+7rV8K/N3+vXgXRaEYTuAScKtflEbA7YnZA5nUdMng8x0kMTQ
# Y73XCd4UGWDfSSZsgaIHGkM/MRIHgmlrfcwPkWqWW9vF+92O6Hw=
# =/Du0
# -----END PGP SIGNATURE-----
# gpg: Signature made Mon 06 Nov 2023 22:35:30 HKT
# gpg: using RSA key A0F66548F04895EBFE6B0B6051A343C7CFFBECA1
# gpg: Good signature from "Cédric Le Goater <clg@redhat.com>" [unknown]
# gpg: aka "Cédric Le Goater <clg@kaod.org>" [unknown]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: A0F6 6548 F048 95EB FE6B 0B60 51A3 43C7 CFFB ECA1
* tag 'pull-vfio-20231106' of https://github.com/legoater/qemu: (22 commits)
vfio/common: Move vfio_host_win_add/del into spapr.c
vfio/spapr: Make vfio_spapr_create/remove_window static
vfio/container: Move spapr specific init/deinit into spapr.c
vfio/container: Move vfio_container_add/del_section_window into spapr.c
vfio/container: Move IBM EEH related functions into spapr_pci_vfio.c
util/uuid: Define UUID_STR_LEN from UUID_NONE string
util/uuid: Remove UUID_FMT_LEN
vfio/pci: Fix buffer overrun when writing the VF token
util/uuid: Add UUID_STR_LEN definition
hw/pci: modify pci_setup_iommu() to set PCIIOMMUOps
test: Add some tests for range and resv-mem helpers
virtio-iommu: Consolidate host reserved regions and property set ones
virtio-iommu: Implement set_iova_ranges() callback
virtio-iommu: Record whether a probe request has been issued
range: Introduce range_inverse_array()
virtio-iommu: Introduce per IOMMUDevice reserved regions
util/reserved-region: Add new ReservedRegion helpers
range: Make range_compare() public
virtio-iommu: Rename reserved_regions into prop_resv_regions
vfio: Collect container iova range info
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This reverts commit 5960f254db since the
previous commit made this situation possible again.
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
This patch modifies pci_setup_iommu() to set PCIIOMMUOps
instead of setting PCIIOMMUFunc. PCIIOMMUFunc is used to
get an address space for a PCI device in vendor specific
way. The PCIIOMMUOps still offers this functionality. But
using PCIIOMMUOps leaves space to add more iommu related
vendor specific operations.
Cc: Kevin Tian <kevin.tian@intel.com>
Cc: Jacob Pan <jacob.jun.pan@linux.intel.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Yi Sun <yi.y.sun@linux.intel.com>
Cc: David Gibson <david@gibson.dropbear.id.au>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Peter Maydell <peter.maydell@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Andrey Smirnov <andrew.smirnov@gmail.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hervé Poussineau <hpoussin@reactos.org>
Cc: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Cc: BALATON Zoltan <balaton@eik.bme.hu>
Cc: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Cc: Jagannathan Raman <jag.raman@oracle.com>
Cc: Matthew Rosato <mjrosato@linux.ibm.com>
Cc: Eric Farman <farman@linux.ibm.com>
Cc: Halil Pasic <pasic@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Thomas Huth <thuth@redhat.com>
Cc: Helge Deller <deller@gmx.de>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
[ clg: - refreshed on latest QEMU
- included hw/remote/iommu.c
- documentation update
- asserts in pci_setup_iommu()
- removed checks on iommu_bus->iommu_ops->get_address_space
- included Elroy PCI host (PA-RISC) ]
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Up to now we were exposing to the RESV_MEM probe requests the
reserved memory regions set though the reserved-regions array property.
Combine those with the host reserved memory regions if any. Those
latter are tagged as RESERVED. We don't have more information about
them besides then cannot be mapped. Reserved regions set by
property have higher priority.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Tested-by: Yanghang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
The implementation populates the array of per IOMMUDevice
host reserved ranges.
It is forbidden to have conflicting sets of host IOVA ranges
to be applied onto the same IOMMU MR (implied by different
host devices).
In case the callback is called after the probe request has
been issues by the driver, a warning is issued.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Tested-by: Yanghang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Add an IOMMUDevice 'probe_done' flag to record that the driver
already issued a probe request on that device.
This will be useful to double check host reserved regions aren't
notified after the probe and hence are not taken into account
by the driver.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Suggested-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Tested-by: Yanghang Liu <yanghliu@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
For the time being the per device reserved regions are
just a duplicate of IOMMU wide reserved regions. Subsequent
patches will combine those with host reserved regions, if any.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Yanghang Liu <yanghliu@redhat.com>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Rename VirtIOIOMMU (nb_)reserved_regions fields with the "prop_" prefix
to highlight those fields are set through a property, at machine level.
They are IOMMU wide.
A subsequent patch will introduce per IOMMUDevice reserved regions
that will include both those IOMMU wide property reserved
regions plus, sometimes, host reserved regions, if the device is
backed by a host device protected by a physical IOMMU. Also change
nb_ prefix by nr_.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
A reserved region is a range tagged with a type. Let's directly use
the Range type in the prospect to reuse some of the library helpers
shipped with the Range type.
Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
vhost blocks migration if logging is not supported to track dirty
memory, and vhost-user blocks it if the log cannot be saved to a shm fd.
vhost-vdpa blocks migration if both hosts do not support all the device's
features using a shadow VQ, for tracking requests and dirty memory.
vhost-scsi blocks migration if storage cannot be shared across hosts,
or if state cannot be migrated.
None of these conditions apply if the old and new qemu processes do
not run concurrently, and if new qemu starts on the same host as old,
which is the case for cpr.
Narrow the scope of these blockers so they only apply to normal mode.
They will not block cpr modes when they are added in subsequent patches.
No functional change until a new mode is added.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1698263069-406971-5-git-send-email-steven.sistare@oracle.com>
This are the easiest cases, where we were already using
VMSTATE_INSTANCE_ID_ANY.
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-3-quintela@redhat.com>
virtio-blk and virtio-scsi invoke virtio_irqfd_notify() to send Used
Buffer Notifications from an IOThread. This involves an eventfd
write(2) syscall. Calling this repeatedly when completing multiple I/O
requests in a row is wasteful.
Use the defer_call() API to batch together virtio_irqfd_notify() calls
made during thread pool (aio=threads), Linux AIO (aio=native), and
io_uring (aio=io_uring) completion processing.
Behavior is unchanged for emulated devices that do not use
defer_call_begin()/defer_call_end() since defer_call() immediately
invokes the callback when called outside a
defer_call_begin()/defer_call_end() region.
fio rw=randread bs=4k iodepth=64 numjobs=8 IOPS increases by ~9% with a
single IOThread and 8 vCPUs. iodepth=1 decreases by ~1% but this could
be noise. Detailed performance data and configuration specifics are
available here:
https://gitlab.com/stefanha/virt-playbooks/-/tree/blk_io_plug-irqfd
This duplicates the BH that virtio-blk uses for batching. The next
commit will remove it.
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20230913200045.1024233-4-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
NR_IOBUS_DEVS was increased to 200 in Linux 2.6.34. By Linux 3.5 it had
increased to 1000 and later ioeventfds were changed to not count against
the limit. But the earlier limit of 200 would already be enough for
kvm_check_many_ioeventfds() to be true, so remove the check.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
infrastructure for vhost-vdpa shadow work
piix south bridge rework
reconnect for vhost-user-scsi
dummy ACPI QTG DSM for cxl
tests, cleanups, fixes all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEXQn9CHHI+FuUyooNKB8NuNKNVGkFAmU06PMPHG1zdEByZWRo
YXQuY29tAAoJECgfDbjSjVRpNIsH/0DlKti86VZLJ6PbNqsnKxoK2gg05TbEhPZU
pQ+RPDaCHpFBsLC5qsoMJwvaEQFe0e49ZFemw7bXRzBxgmbbNnZ9ArCIPqT+rvQd
7UBmyC+kacVyybZatq69aK2BHKFtiIRlT78d9Izgtjmp8V7oyKoz14Esh8wkE+FT
ypHUa70Addi6alNm6BVkm7bxZxi0Wrmf3THqF8ViYvufzHKl7JR5e17fKWEG0BqV
9W7AeHMnzJ7jkTvBGUw7g5EbzFn7hPLTbO4G/VW97k0puS4WRX5aIMkVhUazsRIa
zDOuXCCskUWuRapiCwY0E4g7cCaT8/JR6JjjBaTgkjJgvo5Y8Eg=
=ILek
-----END PGP SIGNATURE-----
Merge tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu into staging
virtio,pc,pci: features, cleanups
infrastructure for vhost-vdpa shadow work
piix south bridge rework
reconnect for vhost-user-scsi
dummy ACPI QTG DSM for cxl
tests, cleanups, fixes all over the place
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
# -----BEGIN PGP SIGNATURE-----
#
# iQFDBAABCAAtFiEEXQn9CHHI+FuUyooNKB8NuNKNVGkFAmU06PMPHG1zdEByZWRo
# YXQuY29tAAoJECgfDbjSjVRpNIsH/0DlKti86VZLJ6PbNqsnKxoK2gg05TbEhPZU
# pQ+RPDaCHpFBsLC5qsoMJwvaEQFe0e49ZFemw7bXRzBxgmbbNnZ9ArCIPqT+rvQd
# 7UBmyC+kacVyybZatq69aK2BHKFtiIRlT78d9Izgtjmp8V7oyKoz14Esh8wkE+FT
# ypHUa70Addi6alNm6BVkm7bxZxi0Wrmf3THqF8ViYvufzHKl7JR5e17fKWEG0BqV
# 9W7AeHMnzJ7jkTvBGUw7g5EbzFn7hPLTbO4G/VW97k0puS4WRX5aIMkVhUazsRIa
# zDOuXCCskUWuRapiCwY0E4g7cCaT8/JR6JjjBaTgkjJgvo5Y8Eg=
# =ILek
# -----END PGP SIGNATURE-----
# gpg: Signature made Sun 22 Oct 2023 02:18:43 PDT
# 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
* tag 'for_upstream' of https://git.kernel.org/pub/scm/virt/kvm/mst/qemu: (62 commits)
intel-iommu: Report interrupt remapping faults, fix return value
MAINTAINERS: Add include/hw/intc/i8259.h to the PC chip section
vhost-user: Fix protocol feature bit conflict
tests/acpi: Update DSDT.cxl with QTG DSM
hw/cxl: Add QTG _DSM support for ACPI0017 device
tests/acpi: Allow update of DSDT.cxl
hw/i386/cxl: ensure maxram is greater than ram size for calculating cxl range
vhost-user: fix lost reconnect
vhost-user-scsi: start vhost when guest kicks
vhost-user-scsi: support reconnect to backend
vhost: move and rename the conn retry times
vhost-user-common: send get_inflight_fd once
hw/i386/pc_piix: Make PIIX4 south bridge usable in PC machine
hw/isa/piix: Implement multi-process QEMU support also for PIIX4
hw/isa/piix: Resolve duplicate code regarding PCI interrupt wiring
hw/isa/piix: Reuse PIIX3's PCI interrupt triggering in PIIX4
hw/isa/piix: Rename functions to be shared for PCI interrupt triggering
hw/isa/piix: Reuse PIIX3 base class' realize method in PIIX4
hw/isa/piix: Share PIIX3's base class with PIIX4
hw/isa/piix: Harmonize names of reset control memory regions
...
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
When the vhost-user is reconnecting to the backend, and if the vhost-user fails
at the get_features in vhost_dev_init(), then the reconnect will fail
and it will not be retriggered forever.
The reason is:
When the vhost-user fails at get_features, the vhost_dev_cleanup will be called
immediately.
vhost_dev_cleanup calls 'memset(hdev, 0, sizeof(struct vhost_dev))'.
The reconnect path is:
vhost_user_blk_event
vhost_user_async_close(.. vhost_user_blk_disconnect ..)
qemu_chr_fe_set_handlers <----- clear the notifier callback
schedule vhost_user_async_close_bh
The vhost->vdev is null, so the vhost_user_blk_disconnect will not be
called, then the event fd callback will not be reinstalled.
All vhost-user devices have this issue, including vhost-user-blk/scsi.
With this patch, if the vdev->vdev is null, the fd callback will still
be reinstalled.
Fixes: 71e076a07d ("hw/virtio: generalise CHR_EVENT_CLOSED handling")
Signed-off-by: Li Feng <fengli@smartx.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20231009044735.941655-6-fengli@smartx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Multiple devices need this macro, move it to a common header.
Signed-off-by: Li Feng <fengli@smartx.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20231009044735.941655-3-fengli@smartx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
vhost-user-scsi has a VirtioDeviceClass->reset() function that calls
->vhost_reset_device(). The other vhost devices don't notify the vhost
device upon reset.
Stateful vhost devices may need to handle device reset in order to free
resources or prevent stale device state from interfering after reset.
Call ->vhost_device_reset() from virtio_reset() so that that vhost
devices are notified of device reset.
This patch affects behavior as follows:
- vhost-kernel: No change in behavior since ->vhost_reset_device() is
not implemented.
- vhost-user: back-ends that negotiate
VHOST_USER_PROTOCOL_F_RESET_DEVICE now receive a
VHOST_USER_DEVICE_RESET message upon device reset. Otherwise there is
no change in behavior. DPDK, SPDK, libvhost-user, and the
vhost-user-backend crate do not negotiate
VHOST_USER_PROTOCOL_F_RESET_DEVICE automatically.
- vhost-vdpa: an extra SET_STATUS 0 call is made during device reset.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20231004014532.1228637-4-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
vhost_kernel_reset_device() invokes RESET_OWNER, which disassociates the
owner process from the device. The device is left non-operational since
SET_OWNER is only called once during startup in vhost_dev_init().
vhost_kernel_reset_device() is never called so this latent bug never
appears. Get rid of vhost_kernel_reset_device() for now. If someone
needs it in the future they'll need to implement it correctly.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20231004014532.1228637-3-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
The VHOST_USER_RESET_OWNER message is deprecated in the spec:
This is no longer used. Used to be sent to request disabling all
rings, but some back-ends interpreted it to also discard connection
state (this interpretation would lead to bugs). It is recommended
that back-ends either ignore this message, or use it to disable all
rings.
The only caller of vhost_user_reset_device() is vhost_user_scsi_reset().
It checks that F_RESET_DEVICE was negotiated before calling it:
static void vhost_user_scsi_reset(VirtIODevice *vdev)
{
VHostSCSICommon *vsc = VHOST_SCSI_COMMON(vdev);
struct vhost_dev *dev = &vsc->dev;
/*
* Historically, reset was not implemented so only reset devices
* that are expecting it.
*/
if (!virtio_has_feature(dev->protocol_features,
VHOST_USER_PROTOCOL_F_RESET_DEVICE)) {
return;
}
if (dev->vhost_ops->vhost_reset_device) {
dev->vhost_ops->vhost_reset_device(dev);
}
}
Therefore VHOST_USER_RESET_OWNER is actually never sent by
vhost_user_reset_device(). Remove the dead code. This effectively moves
the vhost-user protocol specific code from vhost-user-scsi.c into
vhost-user.c where it belongs.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20231004014532.1228637-2-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
(1) The virtio-1.2 specification
<http://docs.oasis-open.org/virtio/virtio/v1.2/virtio-v1.2.html> writes:
> 3 General Initialization And Device Operation
> 3.1 Device Initialization
> 3.1.1 Driver Requirements: Device Initialization
>
> [...]
>
> 7. Perform device-specific setup, including discovery of virtqueues for
> the device, optional per-bus setup, reading and possibly writing the
> device’s virtio configuration space, and population of virtqueues.
>
> 8. Set the DRIVER_OK status bit. At this point the device is “live”.
and
> 4 Virtio Transport Options
> 4.1 Virtio Over PCI Bus
> 4.1.4 Virtio Structure PCI Capabilities
> 4.1.4.3 Common configuration structure layout
> 4.1.4.3.2 Driver Requirements: Common configuration structure layout
>
> [...]
>
> The driver MUST configure the other virtqueue fields before enabling the
> virtqueue with queue_enable.
>
> [...]
(The same statements are present in virtio-1.0 identically, at
<http://docs.oasis-open.org/virtio/virtio/v1.0/virtio-v1.0.html>.)
These together mean that the following sub-sequence of steps is valid for
a virtio-1.0 guest driver:
(1.1) set "queue_enable" for the needed queues as the final part of device
initialization step (7),
(1.2) set DRIVER_OK in step (8),
(1.3) immediately start sending virtio requests to the device.
(2) When vhost-user is enabled, and the VHOST_USER_F_PROTOCOL_FEATURES
special virtio feature is negotiated, then virtio rings start in disabled
state, according to
<https://qemu-project.gitlab.io/qemu/interop/vhost-user.html#ring-states>.
In this case, explicit VHOST_USER_SET_VRING_ENABLE messages are needed for
enabling vrings.
Therefore setting "queue_enable" from the guest (1.1) -- which is
technically "buffered" on the QEMU side until the guest sets DRIVER_OK
(1.2) -- is a *control plane* operation, which -- after (1.2) -- travels
from the guest through QEMU to the vhost-user backend, using a unix domain
socket.
Whereas sending a virtio request (1.3) is a *data plane* operation, which
evades QEMU -- it travels from guest to the vhost-user backend via
eventfd.
This means that operations ((1.1) + (1.2)) and (1.3) travel through
different channels, and their relative order can be reversed, as perceived
by the vhost-user backend.
That's exactly what happens when OVMF's virtiofs driver (VirtioFsDxe) runs
against the Rust-language virtiofsd version 1.7.2. (Which uses version
0.10.1 of the vhost-user-backend crate, and version 0.8.1 of the vhost
crate.)
Namely, when VirtioFsDxe binds a virtiofs device, it goes through the
device initialization steps (i.e., control plane operations), and
immediately sends a FUSE_INIT request too (i.e., performs a data plane
operation). In the Rust-language virtiofsd, this creates a race between
two components that run *concurrently*, i.e., in different threads or
processes:
- Control plane, handling vhost-user protocol messages:
The "VhostUserSlaveReqHandlerMut::set_vring_enable" method
[crates/vhost-user-backend/src/handler.rs] handles
VHOST_USER_SET_VRING_ENABLE messages, and updates each vring's "enabled"
flag according to the message processed.
- Data plane, handling virtio / FUSE requests:
The "VringEpollHandler::handle_event" method
[crates/vhost-user-backend/src/event_loop.rs] handles the incoming
virtio / FUSE request, consuming the virtio kick at the same time. If
the vring's "enabled" flag is set, the virtio / FUSE request is
processed genuinely. If the vring's "enabled" flag is clear, then the
virtio / FUSE request is discarded.
Note that OVMF enables the queue *first*, and sends FUSE_INIT *second*.
However, if the data plane processor in virtiofsd wins the race, then it
sees the FUSE_INIT *before* the control plane processor took notice of
VHOST_USER_SET_VRING_ENABLE and green-lit the queue for the data plane
processor. Therefore the latter drops FUSE_INIT on the floor, and goes
back to waiting for further virtio / FUSE requests with epoll_wait.
Meanwhile OVMF is stuck waiting for the FUSET_INIT response -- a deadlock.
The deadlock is not deterministic. OVMF hangs infrequently during first
boot. However, OVMF hangs almost certainly during reboots from the UEFI
shell.
The race can be "reliably masked" by inserting a very small delay -- a
single debug message -- at the top of "VringEpollHandler::handle_event",
i.e., just before the data plane processor checks the "enabled" field of
the vring. That delay suffices for the control plane processor to act upon
VHOST_USER_SET_VRING_ENABLE.
We can deterministically prevent the race in QEMU, by blocking OVMF inside
step (1.2) -- i.e., in the write to the device status register that
"unleashes" queue enablement -- until VHOST_USER_SET_VRING_ENABLE actually
*completes*. That way OVMF's VCPU cannot advance to the FUSE_INIT
submission before virtiofsd's control plane processor takes notice of the
queue being enabled.
Wait for VHOST_USER_SET_VRING_ENABLE completion by:
- setting the NEED_REPLY flag on VHOST_USER_SET_VRING_ENABLE, and waiting
for the reply, if the VHOST_USER_PROTOCOL_F_REPLY_ACK vhost-user feature
has been negotiated, or
- performing a separate VHOST_USER_GET_FEATURES *exchange*, which requires
a backend response regardless of VHOST_USER_PROTOCOL_F_REPLY_ACK.
Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:vhost)
Cc: Eugenio Perez Martin <eperezma@redhat.com>
Cc: German Maglione <gmaglione@redhat.com>
Cc: Liu Jiang <gerry@linux.alibaba.com>
Cc: Sergio Lopez Pascual <slp@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Albert Esteve <aesteve@redhat.com>
[lersek@redhat.com: work Eugenio's explanation into the commit message,
about QEMU containing step (1.1) until step (1.2)]
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231002203221.17241-8-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The "vhost_set_vring" function already centralizes the common parts of
"vhost_user_set_vring_num", "vhost_user_set_vring_base" and
"vhost_user_set_vring_enable". We'll want to allow some of those callers
to wait for a reply.
Therefore, rebase "vhost_set_vring" from just "vhost_user_write" to
"vhost_user_write_sync", exposing the "wait_for_reply" parameter.
This is purely refactoring -- there is no observable change. That's
because:
- all three callers pass in "false" for "wait_for_reply", which disables
all logic in "vhost_user_write_sync" except the call to
"vhost_user_write";
- the fds=NULL and fd_num=0 arguments of the original "vhost_user_write"
call inside "vhost_set_vring" are hard-coded within
"vhost_user_write_sync".
Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:vhost)
Cc: Eugenio Perez Martin <eperezma@redhat.com>
Cc: German Maglione <gmaglione@redhat.com>
Cc: Liu Jiang <gerry@linux.alibaba.com>
Cc: Sergio Lopez Pascual <slp@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Albert Esteve <aesteve@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231002203221.17241-7-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In order to avoid a forward-declaration for "vhost_user_write_sync" in a
subsequent patch, hoist "vhost_user_write_sync" ->
"vhost_user_get_features" -> "vhost_user_get_u64" just above
"vhost_set_vring".
This is purely code movement -- no observable change.
Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:vhost)
Cc: Eugenio Perez Martin <eperezma@redhat.com>
Cc: German Maglione <gmaglione@redhat.com>
Cc: Liu Jiang <gerry@linux.alibaba.com>
Cc: Sergio Lopez Pascual <slp@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Albert Esteve <aesteve@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231002203221.17241-6-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
At this point, only "vhost_user_write_sync" calls "enforce_reply"; embed
the latter into the former.
This is purely refactoring -- no observable change.
Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:vhost)
Cc: Eugenio Perez Martin <eperezma@redhat.com>
Cc: German Maglione <gmaglione@redhat.com>
Cc: Liu Jiang <gerry@linux.alibaba.com>
Cc: Sergio Lopez Pascual <slp@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Albert Esteve <aesteve@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231002203221.17241-5-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The tails of the "vhost_user_set_vring_addr" and "vhost_user_set_u64"
functions are now byte-for-byte identical. Factor the common tail out to a
new function called "vhost_user_write_sync".
This is purely refactoring -- no observable change.
Cc: "Michael S. Tsirkin" <mst@redhat.com> (supporter:vhost)
Cc: Eugenio Perez Martin <eperezma@redhat.com>
Cc: German Maglione <gmaglione@redhat.com>
Cc: Liu Jiang <gerry@linux.alibaba.com>
Cc: Sergio Lopez Pascual <slp@redhat.com>
Cc: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Tested-by: Albert Esteve <aesteve@redhat.com>
Reviewed-by: Eugenio Pérez <eperezma@redhat.com>
Message-Id: <20231002203221.17241-4-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
