When vfio_realize fails, the mmap_timer used for INTx optimization
isn't freed. As this timer isn't activated yet, the potential impact
is just a piece of leaked memory.
Fixes: ea486926b0 ("vfio-pci: Update slow path INTx algorithm timer related")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
The kvm irqchip notifier is only registered if the device supports
INTx, however it's unconditionally removed in vfio realize error
path. If the assigned device does not support INTx, this will cause
QEMU to crash when vfio realize fails. Change it to conditionally
remove the notifier only if the notify hook is setup.
Before fix:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1
Connection closed by foreign host.
After fix:
(qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,xres=1
Error: vfio 0000:81:11.1: xres and yres properties require display=on
(qemu)
Fixes: c5478fea27 ("vfio/pci: Respond to KVM irqchip change notifier")
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
The major parts of VFIO migration are supported today in QEMU. This
includes basic VFIO migration, device dirty page tracking and precopy
support.
Thus, at this point in time, it seems appropriate to make VFIO migration
non-experimental: remove the x prefix from enable_migration property,
change it to ON_OFF_AUTO and let the default value be AUTO.
In addition, make the following adjustments:
1. When enable_migration is ON and migration is not supported, fail VFIO
device realization.
2. When enable_migration is AUTO (i.e., not explicitly enabled), require
device dirty tracking support. This is because device dirty tracking
is currently the only method to do dirty page tracking, which is
essential for migrating in a reasonable downtime. Setting
enable_migration to ON will not require device dirty tracking.
3. Make migration error and blocker messages more elaborate.
4. Remove error prints in vfio_migration_query_flags().
5. Rename trace_vfio_migration_probe() to
trace_vfio_migration_realize().
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Currently, VFIO bytes_transferred is not reset properly:
1. bytes_transferred is not reset after a VM snapshot (so a migration
following a snapshot will report incorrect value).
2. bytes_transferred is a single counter for all VFIO devices, however
upon migration failure it is reset multiple times, by each VFIO
device.
Fix it by introducing a new function vfio_reset_bytes_transferred() and
calling it during migration and snapshot start.
Remove existing bytes_transferred reset in VFIO migration state
notifier, which is not needed anymore.
Fixes: 3710586caa ("qapi: Add VFIO devices migration stats in Migration stats")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
When vfio_enable_vectors() returns with less than requested nr_vectors
we retry with what kernel reported back. But the retry path doesn't
call vfio_prepare_kvm_msi_virq_batch() and this results in,
qemu-system-aarch64: vfio: Error: Failed to enable 4 MSI vectors, retry with 1
qemu-system-aarch64: ../hw/vfio/pci.c:602: vfio_commit_kvm_msi_virq_batch: Assertion `vdev->defer_kvm_irq_routing' failed
Fixes: dc580d51f7 ("vfio: defer to commit kvm irq routing when enable msi/msix")
Reviewed-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
NVIDIA Turing and newer GPUs implement the MSI-X capability at the offset
previously reserved for use by hypervisors to implement the GPUDirect
Cliques capability. A revised specification provides an alternate
location. Add a config space walk to the quirk to check for conflicts,
allowing us to fall back to the new location or generate an error at the
quirk setup rather than when the real conflicting capability is added
should there be no available location.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
A common helper implementing the realloc algorithm for handling
capabilities.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Robin Voetter <robin@streamhpc.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Loading of a VFIO device's data can take a substantial amount of time as
the device may need to allocate resources, prepare internal data
structures, etc. This can increase migration downtime, especially for
VFIO devices with a lot of resources.
To solve this, VFIO migration uAPI defines "initial bytes" as part of
its precopy data stream. Initial bytes can be used in various ways to
improve VFIO migration performance. For example, it can be used to
transfer device metadata to pre-allocate resources in the destination.
However, for this to work we need to make sure that all initial bytes
are sent and loaded in the destination before the source VM is stopped.
Use migration switchover ack capability to make sure a VFIO device's
initial bytes are sent and loaded in the destination before the source
stops the VM and attempts to complete the migration.
This can significantly reduce migration downtime for some devices.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Pre-copy support allows the VFIO device data to be transferred while the
VM is running. This helps to accommodate VFIO devices that have a large
amount of data that needs to be transferred, and it can reduce migration
downtime.
Pre-copy support is optional in VFIO migration protocol v2.
Implement pre-copy of VFIO migration protocol v2 and use it for devices
that support it. Full description of it can be found in the following
Linux commit: 4db52602a607 ("vfio: Extend the device migration protocol
with PRE_COPY").
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
VFIO migration flags are queried once in vfio_migration_init(). Store
them in VFIOMigration so they can be used later to check the device's
migration capabilities without re-querying them.
This will be used in the next patch to check if the device supports
precopy migration.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Refactor vfio_save_block() to return the size of saved data on success
and -errno on error.
This will be used in next patch to implement VFIO migration pre-copy
support.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: YangHang Liu <yanghliu@redhat.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Include the number of dirty pages on the vfio_get_dirty_bitmap tracepoint.
These are fetched from the newly added return value in
cpu_physical_memory_set_dirty_lebitmap().
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Message-Id: <20230530180556.24441-3-joao.m.martins@oracle.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
vbasedev->name is freed wrongly which leads to garbage VFIO trace log.
Fix it by allocating a dup of vbasedev->name and then free the dup.
Fixes: 2dca1b37a7 ("vfio/pci: add support for VF token")
Suggested-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Alex Williamson <alex.williamson@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
The PCI Resizable BAR (ReBAR) capability is currently hidden from the
VM because the protocol for interacting with the capability does not
support a mechanism for the device to reject an advertised supported
BAR size. However, when assigned to a VM, the act of resizing the
BAR requires adjustment of host resources for the device, which
absolutely can fail. Linux does not currently allow us to reserve
resources for the device independent of the current usage.
The only writable field within the ReBAR capability is the BAR Size
register. The PCIe spec indicates that when written, the device
should immediately begin to operate with the provided BAR size. The
spec however also notes that software must only write values
corresponding to supported sizes as indicated in the capability and
control registers. Writing unsupported sizes produces undefined
results. Therefore, if the hypervisor were to virtualize the
capability and control registers such that the current size is the
only indicated available size, then a write of anything other than
the current size falls into the category of undefined behavior,
where we can essentially expose the modified ReBAR capability as
read-only.
This may seem pointless, but users have reported that virtualizing
the capability in this way not only allows guest software to expose
related features as available (even if only cosmetic), but in some
scenarios can resolve guest driver issues. Additionally, no
regressions in behavior have been reported for this change.
A caveat here is that the PCIe spec requires for compatibility that
devices report support for a size in the range of 1MB to 512GB,
therefore if the current BAR size falls outside that range we revert
to hiding the capability.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230505232308.2869912-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently, VFIO log_sync can be issued while migration is in SETUP
state. However, doing this log_sync is at best redundant and at worst
can fail.
Redundant -- all RAM is marked dirty in migration SETUP state and is
transferred only after migration is set to ACTIVE state, so doing
log_sync during migration SETUP is pointless.
Can fail -- there is a time window, between setting migration state to
SETUP and starting dirty tracking by RAM save_live_setup handler, during
which dirty tracking is still not started. Any VFIO log_sync call that
is issued during this time window will fail. For example, this error can
be triggered by migrating a VM when a GUI is active, which constantly
calls log_sync.
Fix it by skipping VFIO log_sync while migration is in SETUP state.
Fixes: 758b96b61d ("vfio/migrate: Move switch of dirty tracking into vfio_memory_listener")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230403130000.6422-1-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This had been pulled in via qemu/plugin.h from hw/core/cpu.h,
but that will be removed.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230310195252.210956-5-richard.henderson@linaro.org>
[AJB: add various additional cases shown by CI]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230315174331.2959-15-alex.bennee@linaro.org>
Reviewed-by: Emilio Cota <cota@braap.org>
Pick names that align with the section drivers should use them from,
avoiding the confusion of calling a _finalize() function from _exit()
and generalizing the actual _finalize() to handle removing the viommu
blocker.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/167820912978.606734.12740287349119694623.stgit@omen
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that everything has been set up for device dirty page tracking,
query the device for device dirty page tracking support.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-15-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Migrating with vIOMMU will require either tracking maximum
IOMMU supported address space (e.g. 39/48 address width on Intel)
or range-track current mappings and dirty track the new ones
post starting dirty tracking. This will be done as a separate
series, so add a live migration blocker until that is fixed.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-14-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add device dirty page bitmap sync functionality. This uses the device
DMA logging uAPI to sync dirty page bitmap from the device.
Device dirty page bitmap sync is used only if all devices within a
container support device dirty page tracking.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-13-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Extract the VFIO_IOMMU_DIRTY_PAGES ioctl code in vfio_get_dirty_bitmap()
to its own function.
This will help the code to be more readable after next patch will add
device dirty page bitmap sync functionality.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-12-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Add device dirty page tracking start/stop functionality. This uses the
device DMA logging uAPI to start and stop dirty page tracking by device.
Device dirty page tracking is used only if all devices within a
container support device dirty page tracking.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Link: https://lore.kernel.org/r/20230307125450.62409-11-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
According to the device DMA logging uAPI, IOVA ranges to be logged by
the device must be provided all at once upon DMA logging start.
As preparation for the following patches which will add device dirty
page tracking, keep a record of all DMA mapped IOVA ranges so later they
can be used for DMA logging start.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-10-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation to be used in device dirty tracking, move the code that
calculate a iova/end range from the container/section. This avoids
duplication on the common checks across listener callbacks.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-9-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
The checks are replicated against region_add and region_del
and will be soon added in another memory listener dedicated
for dirty tracking.
Move these into a new helper for avoid duplication.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-8-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
In preparation to turn more of the memory listener checks into
common functions, one of the affected places is how we trace when
sections are skipped. Right now there is one for each. Change it
into one single tracepoint `vfio_listener_region_skip` which receives
a name which refers to the callback i.e. region_add and region_del.
Suggested-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-7-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move the code that finds the container host DMA window against a iova
range. This avoids duplication on the common checks across listener
callbacks.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Avihai Horon <avihaih@nvidia.com>
Link: https://lore.kernel.org/r/20230307125450.62409-6-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are already two places where dirty page bitmap allocation and
calculations are done in open code.
To avoid code duplication, introduce VFIOBitmap struct and corresponding
alloc function and use them where applicable.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-5-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
If VFIO dirty pages log start/stop/sync fails during migration,
migration should be aborted as pages dirtied by VFIO devices might not
be reported properly.
This is not the case today, where in such scenario only an error is
printed.
Fix it by aborting migration in the above scenario.
Fixes: 758b96b61d ("vfio/migrate: Move switch of dirty tracking into vfio_memory_listener")
Fixes: b6dd6504e3 ("vfio: Add vfio_listener_log_sync to mark dirty pages")
Fixes: 9e7b0442f2 ("vfio: Add ioctl to get dirty pages bitmap during dma unmap")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-4-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
There are several places where the %m conversion is used if one of
vfio_dma_map(), vfio_dma_unmap() or vfio_get_dirty_bitmap() fail.
The %m usage in these places is wrong since %m relies on errno value while
the above functions don't report errors via errno.
Fix it by using strerror() with the returned value instead.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230307125450.62409-3-joao.m.martins@oracle.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Use the VFIO_CCW() QOM type-checking macro to avoid DO_UPCAST().
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-Id: <20230213170145.45666-7-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
QOM parenthood relationship is:
VFIOCCWDevice -> S390CCWDevice -> CcwDevice -> DeviceState
No need to double-cast, call CCW_DEVICE() on VFIOCCWDevice.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20230213170145.45666-6-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Use the S390_CCW_DEVICE() QOM type-checking macro to avoid DO_UPCAST().
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230213170145.45666-5-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
'cdev' is VFIOCCWDevice's private parent object.
Access it using the S390_CCW_DEVICE() QOM macro.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20230213170145.45666-4-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
QOM parenthood relationship is:
VFIOCCWDevice -> S390CCWDevice -> CcwDevice -> DeviceState
We can directly use the QOM DEVICE() macro to get the parent object.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Eric Farman <farman@linux.ibm.com>
Message-Id: <20230213170145.45666-3-philmd@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Sort the migration section of VFIO trace events file alphabetically
and move two misplaced traces to common.c section.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-11-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Now that v2 protocol implementation has been added, remove the
deprecated v1 implementation.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-10-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Implement the basic mandatory part of VFIO migration protocol v2.
This includes all functionality that is necessary to support
VFIO_MIGRATION_STOP_COPY part of the v2 protocol.
The two protocols, v1 and v2, will co-exist and in the following patches
v1 protocol code will be removed.
There are several main differences between v1 and v2 protocols:
- VFIO device state is now represented as a finite state machine instead
of a bitmap.
- Migration interface with kernel is now done using VFIO_DEVICE_FEATURE
ioctl and normal read() and write() instead of the migration region.
- Pre-copy is made optional in v2 protocol. Support for pre-copy will be
added later on.
Detailed information about VFIO migration protocol v2 and its difference
compared to v1 protocol can be found here [1].
[1]
https://lore.kernel.org/all/20220224142024.147653-10-yishaih@nvidia.com/
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>.
Link: https://lore.kernel.org/r/20230216143630.25610-9-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
To avoid name collisions, rename functions and structs related to VFIO
migration protocol v1. This will allow the two protocols to co-exist
when v2 protocol is added, until v1 is removed. No functional changes
intended.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-8-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Move vfio_dev_get_region_info() logic from vfio_migration_probe() to
vfio_migration_init(). This logic is specific to v1 protocol and moving
it will make it easier to add the v2 protocol implementation later.
No functional changes intended.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-7-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently VFIO migration doesn't implement some kind of intermediate
quiescent state in which P2P DMAs are quiesced before stopping or
running the device. This can cause problems in multi-device migration
where the devices are doing P2P DMAs, since the devices are not stopped
together at the same time.
Until such support is added, block migration of multiple devices.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-6-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
vfio_devices_all_running_and_saving() is used to check if migration is
in pre-copy phase. This is done by checking if migration is in setup or
active states and if all VFIO devices are in pre-copy state, i.e.
_SAVING | _RUNNING.
In VFIO migration protocol v2 pre-copy support is made optional. Hence,
a matching v2 protocol pre-copy state can't be used here.
As preparation for adding v2 protocol, change
vfio_devices_all_running_and_saving() logic such that it doesn't use the
VFIO pre-copy state.
The new equivalent logic checks if migration is in active state and if
all VFIO devices are in running state [1]. No functional changes
intended.
[1] Note that checking if migration is in setup or active states and if
all VFIO devices are in running state doesn't guarantee that we are in
pre-copy phase, thus we check if migration is only in active state.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-5-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Currently, if IOMMU of a VFIO container doesn't support dirty page
tracking, migration is blocked. This is because a DMA-able VFIO device
can dirty RAM pages without updating QEMU about it, thus breaking the
migration.
However, this doesn't mean that migration can't be done at all.
In such case, allow migration and let QEMU VFIO code mark all pages
dirty.
This guarantees that all pages that might have gotten dirty are reported
back, and thus guarantees a valid migration even without VFIO IOMMU
dirty tracking support.
The motivation for this patch is the introduction of iommufd [1].
iommufd can directly implement the /dev/vfio/vfio container IOCTLs by
mapping them into its internal ops, allowing the usage of these IOCTLs
over iommufd. However, VFIO IOMMU dirty tracking is not supported by
this VFIO compatibility API.
This patch will allow migration by hosts that use the VFIO compatibility
API and prevent migration regressions caused by the lack of VFIO IOMMU
dirty tracking support.
[1]
https://lore.kernel.org/kvm/0-v6-a196d26f289e+11787-iommufd_jgg@nvidia.com/
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Link: https://lore.kernel.org/r/20230216143630.25610-4-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
As part of its error flow, vfio_vmstate_change() accesses
MigrationState->to_dst_file without any checks. This can cause a NULL
pointer dereference if the error flow is taken and
MigrationState->to_dst_file is not set.
For example, this can happen if VM is started or stopped not during
migration and vfio_vmstate_change() error flow is taken, as
MigrationState->to_dst_file is not set at that time.
Fix it by checking that MigrationState->to_dst_file is set before using
it.
Fixes: 02a7e71b1e ("vfio: Add VM state change handler to know state of VM")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Link: https://lore.kernel.org/r/20230216143630.25610-3-avihaih@nvidia.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Once that res_compatible is removed, they don't make sense anymore.
We remove the _only preffix. And to make things clearer we rename
them to must_precopy and can_postcopy.
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Nothing assigns to it after previous commit.
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Until previous commit, save_live_pending() was used for ram. Now with
the split into state_pending_estimate() and state_pending_exact() it
is not needed anymore, so remove them.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
