Addition of QTG in following patch requires an update to the test
data.
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Message-Id: <20231012125623.21101-2-Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
pc_get_device_memory_range() finds the device memory size by calculating the
difference between maxram and ram sizes. This calculation makes sense only when
maxram is greater than the ram size. Make sure we check for that before calling
pc_get_device_memory_range().
Signed-off-by: Ani Sinha <anisinha@redhat.com>
Message-Id: <20231011105335.42296-1-anisinha@redhat.com>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@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>
Let's keep the same behavior as vhost-user-blk.
Some old guests kick virtqueue before setting VIRTIO_CONFIG_S_DRIVER_OK.
Signed-off-by: Li Feng <fengli@smartx.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20231009044735.941655-5-fengli@smartx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
If the backend crashes and restarts, the device is broken.
This patch adds reconnect for vhost-user-scsi.
This patch also improves the error messages, and reports some silent errors.
Tested with spdk backend.
Signed-off-by: Li Feng <fengli@smartx.com>
Message-Id: <20231009044735.941655-4-fengli@smartx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
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>
Currently the get_inflight_fd will be sent every time the device is started, and
the backend will allocate shared memory to save the inflight state. If the
backend finds that it receives the second get_inflight_fd, it will release the
previous shared memory, which breaks inflight working logic.
This patch is a preparation for the following patches.
Signed-off-by: Li Feng <fengli@smartx.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Message-Id: <20231009044735.941655-2-fengli@smartx.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
QEMU's PIIX3 implementation actually models the real PIIX4, but with different
PCI IDs. Usually, guests deal just fine with it. Still, in order to provide a
more consistent illusion to guests, allow QEMU's PIIX4 implementation to be used
in the PC machine.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-30-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
So far multi-process QEMU was only implemented for PIIX3. Move the support into
the base class to achieve feature parity between both device models.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-29-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now that both PIIX3 and PIIX4 use piix_set_irq() to trigger PCI IRQs the wiring
in the respective realize methods can be shared, too.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-28-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Speeds up PIIX4 which resolves an old TODO. Also makes PIIX4 compatible with Xen
which relies on pci_bus_fire_intx_routing_notifier() to be fired.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-27-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
PIIX4 will get the same optimizations which are already implemented for
PIIX3.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-26-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Resolves duplicate code. Also makes PIIX4 respect the PIIX3 properties which get
added, too. This allows for using PIIX4 in the PC machine.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-25-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Having a common base class will allow for futher code sharing between PIIX3 and
PIIX4. Moreover, it makes PIIX4 implement the acpi-dev-aml-interface.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-24-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
There is no need for having different names here. Having the same name
further allows code to be shared between PIIX3 and PIIX4.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-23-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In the PC machine, the PIT is created in board code to allow it to be
virtualized with various virtualization techniques. So explicitly disable its
creation in the PC machine via a property which defaults to enabled. Once the
PIIX implementations are consolidated this default will keep Malta working
without further ado.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-22-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
In the PC machine, the PIC is created in board code to allow it to be
virtualized with various virtualization techniques. So explicitly disable its
creation in the PC machine via a property which defaults to enabled. Once the
PIIX implementations are consolidated this default will keep Malta working
without further ado.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-21-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Now that the PIIX3 and PIIX4 device models are sufficiently prepared, their
implementations can be merged into one file for further consolidation.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-20-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
PIIX4 has its own, private PIIX4State structure. PIIX3 has almost the
same structure, provided in a public header. So reuse it and add a
cpu_intr attribute to it which is only used by PIIX4.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-19-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Both implementations are the same and will be shared upon merging.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-18-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Rename the "isa" attribute to align it with PIIX3 for consolidation.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-17-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The Malta board, which is the only user of PIIX4, doesn't connect to the
exported interrupt lines. PIIX3 doesn't expose such interrupt lines
either, so remove them for PIIX4 for simplicity and consistency.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-16-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
TYPE_PIIX3_PCI_DEVICE was the former base class of the Xen and non-Xen variants
of the PIIX3 ISA device models. It will become the base class for the PIIX3 and
PIIX4 device models, so drop the "3" from the type names.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-15-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The power management controller is an integral part of PIIX3 (function 3). So
create it as part of the south bridge.
Note that the ACPI function is optional in QEMU. This is why it gets
object_initialize_child()'ed in realize rather than in instance_init.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-14-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The USB controller is an integral part of PIIX3 (function 2). So create
it as part of the south bridge.
Note that the USB function is optional in QEMU. This is why it gets
object_initialize_child()'ed in realize rather than in instance_init.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-13-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The IDE controller is an integral part of PIIX3 (function 1). So create it as
part of the south bridge.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-12-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Makes the south bridges a bit more self-contained and aligns PIIX3 more with
PIIX4. The latter is needed for consolidating the PIIX south bridges.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-11-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Thie PIIX3 south bridge implements both the PIC and the ISA bus, so wiring the
interrupts there makes the device model more self-contained. Furthermore, this
allows the ISA interrupts to be wired to internal child devices in
pci_piix3_realize() which will be performed in subsequent patches.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-10-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When the board assigns the ISA IRQs after the device's realize(), internal
devices such as the RTC can't be wired in ich9_lpc_realize() since the qemu_irqs
are still NULL. Fix that by assigning the ISA interrupts before realize().
This change is necessary for PIIX consolidation because PIIX4 wires the RTC
interrupts in its realize() method, so PIIX3 needs to do so as well. Since the
PC and Q35 boards share RTC code, and since PIIX3 needs the change, ICH9 needs
to be adapted as well.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-9-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
TYPE_PIIX3_DEVICE doesn't instantiate a PIC since it relies on the board to do
so. The "pic" attribute, however, suggests that there is one. Rename the
attribute to reflect that it represents ISA interrupt lines. Use the same naming
convention as in the VIA south bridges as well as in TYPE_I82378.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-8-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The variable is never used by its declared type. Eliminate it.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-7-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Avoid assigning the private member of struct PIIX3State from outside which goes
against best QOM practices. Instead, implement best QOM practice by adding an
"isa-irqs" array property to TYPE_PIIX3_DEVICE and assign it in board code, i.e.
from outside.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-6-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
PIIX_NUM_PIC_IRQS is assumed to be the same as ISA_NUM_IRQS, otherwise
inconsistencies can occur.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-5-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Unlike its PIIX4 counterpart, TYPE_PIIX3_DEVICE doesn't instantiate a PIC
itself. Instead, it relies on the board to do so. This means that the board
needs to wire the ISA IRQs to the PIIX3 device model. As long as the board
assigns the ISA IRQs after PIIX3's realize(), internal devices can't be wired in
pci_piix3_realize() since the qemu_irqs are still NULL. Fix that by assigning
the ISA interrupts before realize(). This will allow for embedding child devices
into the host device as already done for PIIX4.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-4-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The next patches will need to take advantage of it.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20231007123843.127151-3-shentey@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
By being the only entity assigning a non-NULL value to "rtc_irq", the first if
statement determines whether the second if statement is executed. So merge the
two statements into one.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Message-Id: <20231007123843.127151-2-shentey@gmail.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
When the given uuid is already present in the hash table,
virtio_add_resource() does not add the passed VirtioSharedObject. In
this case, free it in the callers to avoid leaking memory. This fixed
the following `make check` error, when built with --enable-sanitizers:
4/166 qemu:unit / test-virtio-dmabuf ERROR 1.51s exit status 1
==7716==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 320 byte(s) in 20 object(s) allocated from:
#0 0x7f6fc16e3808 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cc:144
#1 0x7f6fc1503e98 in g_malloc (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x57e98)
#2 0x564d63cafb6b in test_add_invalid_resource ../tests/unit/test-virtio-dmabuf.c:100
#3 0x7f6fc152659d (/lib/x86_64-linux-gnu/libglib-2.0.so.0+0x7a59d)
SUMMARY: AddressSanitizer: 320 byte(s) leaked in 20 allocation(s).
The changes at virtio_add_resource() itself are not strictly necessary
for the memleak fix, but they make it more obvious that, on an error
return, the passed object is not added to the hash.
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Message-Id: <c61c13f9a0c67dec473bdbfc8789c29ef26c900b.1696624734.git.quic_mathbern@quicinc.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Albert Esteve <aesteve@redhat.com>
Signed-off-by: Matheus Tavares Bernardino <<a href="mailto:quic_mathbern@quicinc.com" target="_blank">quic_mathbern@quicinc.com</a>><br>
Currently, the one-shot (mode 1) PIT expires far too quickly,
due to the output being set under the wrong logic.
This change fixes the one-shot PIT mode to behave similarly to mode 0.
TESTED: using the one-shot PIT mode to calibrate a local apic timer.
Signed-off-by: Damien Zammit <damien@zamaudio.com>
Message-Id: <20230226015755.52624-1-damien@zamaudio.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Commit 6103451aeb ("hw/i386: Build-time assertion on pc/q35 reset register
being identical.") introduced a build-time check where the addresses of the
reset registers are expected to be equal. Back then rev3 of the FADT was used
which required the reset register to be populated and there was common code.
In commit 3a3fcc75f9 ("pc: acpi: force FADT rev1 for 440fx based machine
types") the FADT was downgraded to rev1 for PIIX where the reset register isn't
available. Thus, there is no need for the assertion any longer, so remove it.
Signed-off-by: Bernhard Beschow <shentey@gmail.com>
Reviewed-by: Ani Sinha <anisinha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20231004092355.12929-1-shentey@gmail.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>
Coverity scan reports multiple false-positive "defects" for the
following series of actions in virtio.c:
MemoryRegionCache indirect_desc_cache;
address_space_cache_init_empty(&indirect_desc_cache);
address_space_cache_destroy(&indirect_desc_cache);
For some reason it's unable to recognize the dependency between 'mrs.mr'
and 'fv' and insists that '!mrs.mr' check in address_space_cache_destroy
may take a 'false' branch, even though it is explicitly initialized to
NULL in the address_space_cache_init_empty():
*** CID 1522371: Memory - illegal accesses (UNINIT)
/qemu/hw/virtio/virtio.c: 1627 in virtqueue_split_pop()
1621 }
1622
1623 vq->inuse++;
1624
1625 trace_virtqueue_pop(vq, elem, elem->in_num, elem->out_num);
1626 done:
>>> CID 1522371: Memory - illegal accesses (UNINIT)
>>> Using uninitialized value "indirect_desc_cache.fv" when
>>> calling "address_space_cache_destroy".
1627 address_space_cache_destroy(&indirect_desc_cache);
1628
1629 return elem;
1630
1631 err_undo_map:
1632 virtqueue_undo_map_desc(out_num, in_num, iov);
** CID 1522370: Memory - illegal accesses (UNINIT)
Instead of trying to silence these false positive reports in 4
different places, initializing 'fv' as well, as this doesn't result
in any noticeable performance impact.
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>
Message-Id: <20231009104322.3085887-1-i.maximets@ovn.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.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>
In the vhost_user_set_vring_addr() function, we calculate
"reply_supported" unconditionally, even though we'll only need it if
"wait_for_reply" is also true.
Restrict the scope of "reply_supported" to the minimum.
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: 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: <20231002203221.17241-3-lersek@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
