virtio: skip legacy support check on machine types less than 5.1

Commit 9b3a35ec82 ("virtio: verify that legacy support is not accidentally
on") added a check that returns an error if legacy support

virtio: skip legacy support check on machine types less than 5.1

Commit 9b3a35ec82 ("virtio: verify that legacy support is not accidentally
on") added a check that returns an error if legacy support is on, but the
device does not support legacy.

Unfortunately some devices were wrongly declared legacy capable even if
they were not (e.g vhost-vsock).

To avoid migration issues, we add a virtio-device property
(x-disable-legacy-check) to skip the legacy error, printing a warning
instead, for machine types < 5.1.

Cc: qemu-stable@nongnu.org
Fixes: 9b3a35ec82 ("virtio: verify that legacy support is not accidentally on")
Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Suggested-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>
Message-Id: <20200921122506.82515-2-sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/ehabkost/tags/machine-next-pull-request' into staging

QOM queue, 2020-09-18

Fixes:
* Error value corrections (Markus Armbruster)
* Correct object_class_dynamic

Merge remote-tracking branch 'remotes/ehabkost/tags/machine-next-pull-request' into staging

QOM queue, 2020-09-18

Fixes:
* Error value corrections (Markus Armbruster)
* Correct object_class_dynamic_cast_assert() documentation (Eduardo Habkost)
* Ensure objects using QEMU_ALIGNED are properly aligned (Richard Henderson)

QOM cleanups (Eduardo Habkost):
* Rename some constants
* Simplify parameters of OBJECT_DECLARE* macros
* Additional DECLARE_*CHECKER* usage
* Additional OBJECT_DECLARE_TYPE usage
* Additional OBJECT_DECLARE_SIMPLE_TYPE usage

# gpg: Signature made Fri 18 Sep 2020 21:45:29 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/tags/machine-next-pull-request:
Use OBJECT_DECLARE_SIMPLE_TYPE when possible
Use OBJECT_DECLARE_TYPE when possible
qom: Remove module_obj_name parameter from OBJECT_DECLARE* macros
qom: Remove ParentClassType argument from OBJECT_DECLARE_SIMPLE_TYPE
scripts/codeconverter: Update to latest version
target/s390x: Set instance_align on S390CPU TypeInfo
target/riscv: Set instance_align on RISCVCPU TypeInfo
target/ppc: Set instance_align on PowerPCCPU TypeInfo
target/arm: Set instance_align on CPUARM TypeInfo
qom: Allow objects to be allocated with increased alignment
qom: Correct error values in two contracts
qom: Clean up object_property_get_enum()'s error value
qom: Correct object_class_dynamic_cast_assert() documentation
sifive: Use DECLARE_*CHECKER* macros
sifive: Move QOM typedefs and add missing includes
sifive_u: Rename memmap enum constants
sifive_e: Rename memmap enum constants

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

Use OBJECT_DECLARE_TYPE when possible

This converts existing DECLARE_OBJ_CHECKERS usage to
OBJECT_DECLARE_TYPE when possible.

$ ./scripts/codeconverter/converter.py -i \
--pattern=AddObjectDecl

Use OBJECT_DECLARE_TYPE when possible

This converts existing DECLARE_OBJ_CHECKERS usage to
OBJECT_DECLARE_TYPE when possible.

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

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Acked-by: Paul Durrant <paul@xen.org>
Message-Id: <20200916182519.415636-5-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/ehabkost/tags/machine-next-pull-request' into staging

QOM boilerplate cleanup

Documentation build fix:
* memory: Remove kernel-doc comment marker (Eduardo Habk

Merge remote-tracking branch 'remotes/ehabkost/tags/machine-next-pull-request' into staging

QOM boilerplate cleanup

Documentation build fix:
* memory: Remove kernel-doc comment marker (Eduardo Habkost)

QOM cleanups:
* Rename QOM macros for consistency between
TYPE_* and type checking constants (Eduardo Habkost)

QOM new macros:
* OBJECT_DECLARE_* and OBJECT_DEFINE_* macros (Daniel P. Berrangé)
* DECLARE_*_CHECKER macros (Eduardo Habkost)

Automated QOM boilerplate changes:
* Automated changes to use DECLARE_*_CHECKER (Eduardo Habkost
* Automated changes to use OBJECT_DECLARE* (Eduardo Habkost)

# gpg: Signature made Thu 10 Sep 2020 19:17:49 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/tags/machine-next-pull-request: (33 commits)
virtio-vga: Use typedef name for instance_size
vhost-user-vga: Use typedef name for instance_size
xilinx_axienet: Use typedef name for instance_size
lpc_ich9: Use typedef name for instance_size
omap_intc: Use typedef name for instance_size
xilinx_axidma: Use typedef name for instance_size
tusb6010: Rename TUSB to TUSB6010
pc87312: Rename TYPE_PC87312_SUPERIO to TYPE_PC87312
vfio: Rename PCI_VFIO to VFIO_PCI
usb: Rename USB_SERIAL_DEV to USB_SERIAL
sabre: Rename SABRE_DEVICE to SABRE
rs6000_mc: Rename RS6000MC_DEVICE to RS6000MC
filter-rewriter: Rename FILTER_COLO_REWRITER to FILTER_REWRITER
esp: Rename ESP_STATE to ESP
ahci: Rename ICH_AHCI to ICH9_AHCI
vmgenid: Rename VMGENID_DEVICE to TYPE_VMGENID
vfio: Rename VFIO_AP_DEVICE_TYPE to TYPE_VFIO_AP_DEVICE
dev-smartcard-reader: Rename CCID_DEV_NAME to TYPE_USB_CCID_DEV
ap-device: Rename AP_DEVICE_TYPE to TYPE_AP_DEVICE
gpex: Fix type checking function name
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

Use DECLARE_*CHECKER* macros

Generated using:

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

Reviewed-by: Daniel P. Berrangé <berrange@redha

Use DECLARE_*CHECKER* macros

Generated using:

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

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-12-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-13-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-14-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

show more ...

Move QOM typedefs and add missing includes

Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TY

Move QOM typedefs and add missing includes

Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.

Patch generated using:

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

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

Followed by:

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

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

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,pci: bugfixes

Minor bugfixes all over the places, including one CVE.

Additionally, a fix for an ancient bug in migr

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,pci: bugfixes

Minor bugfixes all over the places, including one CVE.

Additionally, a fix for an ancient bug in migration -
one has to wonder how come no one noticed.

The fix is also non-trivial since we dare not break all
existing machine types with pci - we have a work around
in the works, for now we just skip the work-around for
old machine types.

Great job by Hogan Wang noticing, debugging and fixing it,
and thanks to Dr. David Alan Gilbert for reviewing the patches.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 27 Jul 2020 16:34:58 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:
virtio-pci: fix virtio_pci_queue_enabled()
MAINTAINERS: Cover the firmware JSON schema
vhost-vdpa :Fix Coverity CID 1430270 / CID 1420267
libvhost-user: Report descriptor index on panic
Fix vhost-user buffer over-read on ram hot-unplug
hw/pci-host: save/restore pci host config register
virtio-mem-pci: force virtio version 1

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

virtio-pci: fix virtio_pci_queue_enabled()

In legacy mode, virtio_pci_queue_enabled() falls back to
virtio_queue_enabled() to know if the queue is enabled.

But virtio_queue_enabled() calls again vi

virtio-pci: fix virtio_pci_queue_enabled()

In legacy mode, virtio_pci_queue_enabled() falls back to
virtio_queue_enabled() to know if the queue is enabled.

But virtio_queue_enabled() calls again virtio_pci_queue_enabled()
if k->queue_enabled is set. This ends in a crash after a stack
overflow.

The problem can be reproduced with
"-device virtio-net-pci,disable-legacy=off,disable-modern=true
-net tap,vhost=on"

And a look to the backtrace is very explicit:

...
#4 0x000000010029a438 in virtio_queue_enabled ()
#5 0x0000000100497a9c in virtio_pci_queue_enabled ()
...
#130902 0x000000010029a460 in virtio_queue_enabled ()
#130903 0x0000000100497a9c in virtio_pci_queue_enabled ()
#130904 0x000000010029a460 in virtio_queue_enabled ()
#130905 0x0000000100454a20 in vhost_net_start ()
...

This patch fixes the problem by introducing a new function
for the legacy case and calls it from virtio_pci_queue_enabled().
It also calls it from virtio_queue_enabled() to avoid code duplication.

Fixes: f19bcdfedd53 ("virtio-pci: implement queue_enabled method")
Cc: Jason Wang <jasowang@redhat.com>
Cc: Cindy Lu <lulu@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
Message-Id: <20200727153319.43716-1-lvivier@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

acpi,virtio,pc: bugfixes

Fix bug in ACPI which were tripping up guests.
Fix a use-after-free with hotplug of virtio devices

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

acpi,virtio,pc: bugfixes

Fix bug in ACPI which were tripping up guests.
Fix a use-after-free with hotplug of virtio devices.
Block ability to create legacy devices which shouldn't have been
there in the first place.
Fix migration error handling with balloon.
Drop some dead code in virtio.
vtd emulation fixup.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 22 Jul 2020 13:07:26 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:
virtio-pci: Changed vdev to proxy for VirtIO PCI BAR callbacks.
intel_iommu: Use correct shift for 256 bits qi descriptor
virtio: verify that legacy support is not accidentally on
virtio: list legacy-capable devices
virtio-balloon: Replace free page hinting references to 'report' with 'hint'
virtio-balloon: Add locking to prevent possible race when starting hinting
virtio-balloon: Prevent guest from starting a report when we didn't request one
virtio: Drop broken and superfluous object_property_set_link()
acpi: accept byte and word access to core ACPI registers

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

virtio: list legacy-capable devices

Several types of virtio devices had already been around before the
virtio standard was specified. These devices support virtio in legacy
(and transitional) mode.

virtio: list legacy-capable devices

Several types of virtio devices had already been around before the
virtio standard was specified. These devices support virtio in legacy
(and transitional) mode.

Devices that have been added in the virtio standard are considered
non-transitional (i.e. with no support for legacy virtio).

Provide a helper function so virtio transports can figure that out
easily.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20200707105446.677966-2-cohuck@redhat.com>
Cc: qemu-stable@nongnu.org
Acked-by: Halil Pasic <pasic@linux.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pci, pc: fixes, features

Bugfixes all over the place.
HMAT support.
New flags for vhost-user-blk utility.
Auto-tuni

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pci, pc: fixes, features

Bugfixes all over the place.
HMAT support.
New flags for vhost-user-blk utility.
Auto-tuning of seg max for virtio storage.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Mon 06 Jan 2020 17:05:05 GMT
# 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: (32 commits)
intel_iommu: add present bit check for pasid table entries
intel_iommu: a fix to vtd_find_as_from_bus_num()
virtio-net: delete also control queue when TX/RX deleted
virtio: reset region cache when on queue deletion
virtio-mmio: update queue size on guest write
tests: add virtio-scsi and virtio-blk seg_max_adjust test
virtio: make seg_max virtqueue size dependent
hw: fix using 4.2 compat in 5.0 machine types for i440fx/q35
vhost-user-scsi: reset the device if supported
vhost-user: add VHOST_USER_RESET_DEVICE to reset devices
hw/pci/pci_host: Let pci_data_[read/write] use unsigned 'size' argument
hw/pci/pci_host: Remove redundant PCI_DPRINTF()
virtio-mmio: Clear v2 transport state on soft reset
ACPI: add expected files for HMAT tests (acpihmat)
tests/bios-tables-test: add test cases for ACPI HMAT
tests/numa: Add case for QMP build HMAT
hmat acpi: Build Memory Side Cache Information Structure(s)
hmat acpi: Build System Locality Latency and Bandwidth Information Structure(s)
hmat acpi: Build Memory Proximity Domain Attributes Structure(s)
numa: Extend CLI to provide memory side cache information
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

virtio: don't enable notifications during polling

Virtqueue notifications are not necessary during polling, so we disable
them. This allows the guest driver to avoid MMIO vmexits.
Unfortunately the

virtio: don't enable notifications during polling

Virtqueue notifications are not necessary during polling, so we disable
them. This allows the guest driver to avoid MMIO vmexits.
Unfortunately the virtio-blk and virtio-scsi handler functions re-enable
notifications, defeating this optimization.

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

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

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191209210957.65087-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

virtio-pci: disable vring processing when bus-mastering is disabled

Currently the SLOF firmware for pseries guests will disable/re-enable
a PCI device multiple times via IO/MEM/MASTER bits of PCI_CO

virtio-pci: disable vring processing when bus-mastering is disabled

Currently the SLOF firmware for pseries guests will disable/re-enable
a PCI device multiple times via IO/MEM/MASTER bits of PCI_COMMAND
register after the initial probe/feature negotiation, as it tends to
work with a single device at a time at various stages like probing
and running block/network bootloaders without doing a full reset
in-between.

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

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

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

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

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

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

progress = virtio_queue_notify_aio_vq(vq);

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

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

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

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

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

"virtio: zero sized buffers are not allowed"

or

"virtio-blk missing headers"

and puts the device in an error state.

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

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

NOTES:

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

Cc: David Gibson <david@gibson.dropbear.id.au>,
Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Message-Id: <20191120005003.27035-1-mdroth@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

virtio: add ability to delete vq through a pointer

Devices tend to maintain vq pointers, allow deleting them trough a vq pointer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Dav

virtio: add ability to delete vq through a pointer

Devices tend to maintain vq pointers, allow deleting them trough a vq pointer.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pci: fixes

A couple of bugfixes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 06

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio, pci: fixes

A couple of bugfixes.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Wed 06 Nov 2019 12:00:19 GMT
# gpg: using RSA key 281F0DB8D28D5469
# 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:
virtio: notify virtqueue via host notifier when available
hw/i386: AMD-Vi IVRS DMA alias support
pci: Use PCI aliases when determining device IOMMU address space

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

virtio: notify virtqueue via host notifier when available

Host notifiers are used in several cases:
1. Traditional ioeventfd where virtqueue notifications are handled in
the main loop thread.
2.

virtio: notify virtqueue via host notifier when available

Host notifiers are used in several cases:
1. Traditional ioeventfd where virtqueue notifications are handled in
the main loop thread.
2. IOThreads (aio_handle_output) where virtqueue notifications are
handled in an IOThread AioContext.
3. vhost where virtqueue notifications are handled by kernel vhost or
a vhost-user device backend.

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

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

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

Reported-by: Felipe Franciosi <felipe@nutanix.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191105140946.165584-1-stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio: features, cleanups

virtio net failover
rcu cleanup

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Sign

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio: features, cleanups

virtio net failover
rcu cleanup

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 29 Oct 2019 22:58:14 GMT
# gpg: using RSA key 281F0DB8D28D5469
# 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:
virtio: Use auto rcu_read macros
virtio_net: use RCU_READ_LOCK_GUARD
virtio/vhost: Use auto_rcu_read macros
vfio: unplug failover primary device before migration
net/virtio: add failover support
libqos: tolerate wait-unplug migration state
migration: add new migration state wait-unplug
migration: allow unplug during migration for failover devices
qapi: add failover negotiated event
qapi: add unplug primary event
pci: mark device having guest unplug request pending
pci: mark devices partially unplugged
pci: add option for net failover
qdev/qbus: add hidden device support

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

net/virtio: add failover support

This patch adds support to handle failover device pairs of a virtio-net
device and a (vfio-)pci device, where the virtio-net acts as the standby
device and the (vfio

net/virtio: add failover support

This patch adds support to handle failover device pairs of a virtio-net
device and a (vfio-)pci device, where the virtio-net acts as the standby
device and the (vfio-)pci device as the primary.

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

To achieve this we need:

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

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

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

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

Signed-off-by: Jens Freimann <jfreimann@redhat.com>
Message-Id: <20191029114905.6856-11-jfreimann@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

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

# gpg: Signature made Tue 29 Oct 2019 02:33:36 GMT
# gpg: using RSA key EF04965B398D6211
# gpg: Good

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

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

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

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

virtio: new post_load hook

Post load hook in virtio vmsd is called early while device is processed,
and when VirtIODevice core isn't fully initialized. Most device
specific code isn't ready to deal

virtio: new post_load hook

Post load hook in virtio vmsd is called early while device is processed,
and when VirtIODevice core isn't fully initialized. Most device
specific code isn't ready to deal with a device in such state, and
behaves weirdly.

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

Cc: qemu-stable@nongnu.org
Suggested-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mikhail Sennikovsky <mikhail.sennikovskii@cloud.ionos.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>

show more ...

Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2019-10-28' into staging

Block patches for softfreeze:
- iotest patches
- Improve performance of the mirror block job in write-blocking

Merge remote-tracking branch 'remotes/maxreitz/tags/pull-block-2019-10-28' into staging

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

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

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

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio: features, tests

libqos update with support for virtio 1.
Packed ring support for virtio.

Signed-off-by: Michael S.

Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio: features, tests

libqos update with support for virtio 1.
Packed ring support for virtio.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Fri 25 Oct 2019 12:47:59 BST
# gpg: using RSA key 281F0DB8D28D5469
# 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: (25 commits)
virtio: drop unused virtio_device_stop_ioeventfd() function
libqos: add VIRTIO PCI 1.0 support
libqos: extract Legacy virtio-pci.c code
libqos: make the virtio-pci BAR index configurable
libqos: expose common virtqueue setup/cleanup functions
libqos: add MSI-X callbacks to QVirtioPCIDevice
libqos: pass full QVirtQueue to set_queue_address()
libqos: add iteration support to qpci_find_capability()
libqos: access VIRTIO 1.0 vring in little-endian
libqos: implement VIRTIO 1.0 FEATURES_OK step
libqos: enforce Device Initialization order
libqos: add missing virtio-9p feature negotiation
tests/virtio-blk-test: set up virtqueue after feature negotiation
virtio-scsi-test: add missing feature negotiation
libqos: extend feature bits to 64-bit
libqos: read QVIRTIO_MMIO_VERSION register
tests/virtio-blk-test: read config space after feature negotiation
virtio: add property to enable packed virtqueue
vhost_net: enable packed ring support
virtio: event suppression support for packed ring
...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

show more ...

include: Move endof() up from hw/virtio/virtio.h

endof() is a useful macro, we can make use of it outside of virtio.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@red

include: Move endof() up from hw/virtio/virtio.h

endof() is a useful macro, we can make use of it outside of virtio.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20191011152814.14791-2-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

show more ...

virtio: drop unused virtio_device_stop_ioeventfd() function

virtio_device_stop_ioeventfd() has not been used since commit
310837de6c1e0badfd736b1b316b1698c53120a7 ("virtio: introduce
grab/release_io

virtio: drop unused virtio_device_stop_ioeventfd() function

virtio_device_stop_ioeventfd() has not been used since commit
310837de6c1e0badfd736b1b316b1698c53120a7 ("virtio: introduce
grab/release_ioeventfd to fix vhost") in 2016.

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

Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20191021150343.30742-1-stefanha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...

virtio: add property to enable packed virtqueue

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
M

virtio: add property to enable packed virtqueue

Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Reviewed-by: Jens Freimann <jfreimann@redhat.com>
Message-Id: <20191025083527.30803-9-eperezma@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

show more ...