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2023-10-20migration: simplify notifiersSteve Sistare1-3/+3
Pass the callback function to add_migration_state_change_notifier so that migration can initialize the notifier on add and clear it on delete, which simplifies the call sites. Shorten the function names so the extra arg can be added more legibly. Hide the global notifier list in a new function migration_call_notifiers, and make it externally visible so future live update code can call it. No functional change. Signed-off-by: Steve Sistare <steven.sistare@oracle.com> Reviewed-by: Peter Xu <peterx@redhat.com> Tested-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-ID: <1686148954-250144-1-git-send-email-steven.sistare@oracle.com>
2023-10-20migration: simplify blockersSteve Sistare1-14/+2
Modify migrate_add_blocker and migrate_del_blocker to take an Error ** reason. This allows migration to own the Error object, so that if an error occurs in migrate_add_blocker, migration code can free the Error and clear the client handle, simplifying client code. It also simplifies the migrate_del_blocker call site. In addition, this is a pre-requisite for a proposed future patch that would add a mode argument to migration requests to support live update, and maintain a list of blockers for each mode. A blocker may apply to a single mode or to multiple modes, and passing Error** will allow one Error object to be registered for multiple modes. No functional change. Signed-off-by: Steve Sistare <steven.sistare@oracle.com> Tested-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Michael Galaxy <mgalaxy@akamai.com> Reviewed-by: Peter Xu <peterx@redhat.com> Reviewed-by: Juan Quintela <quintela@redhat.com> Signed-off-by: Juan Quintela <quintela@redhat.com> Message-ID: <1697634216-84215-1-git-send-email-steven.sistare@oracle.com>
2023-09-11vfio/migration: Block VFIO migration with background snapshotAvihai Horon1-1/+10
Background snapshot allows creating a snapshot of the VM while it's running and keeping it small by not including dirty RAM pages. The way it works is by first stopping the VM, saving the non-iterable devices' state and then starting the VM and saving the RAM while write protecting it with UFFD. The resulting snapshot represents the VM state at snapshot start. VFIO migration is not compatible with background snapshot. First of all, VFIO device state is not even saved in background snapshot because only non-iterable device state is saved. But even if it was saved, after starting the VM, a VFIO device could dirty pages without it being detected by UFFD write protection. This would corrupt the snapshot, as the RAM in it would not represent the RAM at snapshot start. To prevent this, block VFIO migration with background snapshot. Signed-off-by: Avihai Horon <avihaih@nvidia.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11vfio/migration: Block VFIO migration with postcopy migrationAvihai Horon1-0/+22
VFIO migration is not compatible with postcopy migration. A VFIO device in the destination can't handle page faults for pages that have not been sent yet. Doing such migration will cause the VM to crash in the destination: qemu-system-x86_64: VFIO_MAP_DMA failed: Bad address qemu-system-x86_64: vfio_dma_map(0x55a28c7659d0, 0xc0000, 0xb000, 0x7f1b11a00000) = -14 (Bad address) qemu: hardware error: vfio: DMA mapping failed, unable to continue To prevent this, block VFIO migration with postcopy migration. Reported-by: Yanghang Liu <yanghliu@redhat.com> Signed-off-by: Avihai Horon <avihaih@nvidia.com> Tested-by: Yanghang Liu <yanghliu@redhat.com> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11vfio/migration: Add P2P support for VFIO migrationAvihai Horon1-3/+43
VFIO migration uAPI defines an optional intermediate P2P quiescent state. While in the P2P quiescent state, P2P DMA transactions cannot be initiated by the device, but the device can respond to incoming ones. Additionally, all outstanding P2P transactions are guaranteed to have been completed by the time the device enters this state. The purpose of this state is to support migration of multiple devices that might do P2P transactions between themselves. Add support for P2P migration by transitioning all the devices to the P2P quiescent state before stopping or starting the devices. Use the new VMChangeStateHandler prepare_cb to achieve that behavior. This will allow migration of multiple VFIO devices if all of them support P2P migration. Signed-off-by: Avihai Horon <avihaih@nvidia.com> Tested-by: YangHang Liu <yanghliu@redhat.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11vfio/migration: Refactor PRE_COPY and RUNNING state checksJoao Martins1-6/+4
Move the PRE_COPY and RUNNING state checks to helper functions. This is in preparation for adding P2P VFIO migration support, where these helpers will also test for PRE_COPY_P2P and RUNNING_P2P states. Signed-off-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Avihai Horon <avihaih@nvidia.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Tested-by: YangHang Liu <yanghliu@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-09-11vfio/migration: Move from STOP_COPY to STOP in vfio_save_cleanup()Avihai Horon1-6/+13
Changing the device state from STOP_COPY to STOP can take time as the device may need to free resources and do other operations as part of the transition. Currently, this is done in vfio_save_complete_precopy() and therefore it is counted in the migration downtime. To avoid this, change the device state from STOP_COPY to STOP in vfio_save_cleanup(), which is called after migration has completed and thus is not part of migration downtime. Signed-off-by: Avihai Horon <avihaih@nvidia.com> Tested-by: YangHang Liu <yanghliu@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10vfio/migration: Return bool type for vfio_migration_realize()Zhenzhong Duan1-5/+10
Make vfio_migration_realize() adhere to the convention of other realize() callbacks(like qdev_realize) by returning bool instead of int. Suggested-by: Cédric Le Goater <clg@redhat.com> Suggested-by: Joao Martins <joao.m.martins@oracle.com> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-07-10vfio/migration: Free resources when vfio_migration_realize failsZhenzhong Duan1-10/+23
When vfio_realize() succeeds, hot unplug will call vfio_exitfn() to free resources allocated in vfio_realize(); when vfio_realize() fails, vfio_exitfn() is never called and we need to free resources in vfio_realize(). In the case that vfio_migration_realize() fails, e.g: with -only-migratable & enable-migration=off, we see below: (qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off 0000:81:11.1: Migration disabled Error: disallowing migration blocker (--only-migratable) for: 0000:81:11.1: Migration is disabled for VFIO device If we hotplug again we should see same log as above, but we see: (qemu) device_add vfio-pci,host=81:11.1,id=vfio1,bus=root1,enable-migration=off Error: vfio 0000:81:11.1: device is already attached That's because some references to VFIO device isn't released. For resources allocated in vfio_migration_realize(), free them by jumping to out_deinit path with calling a new function vfio_migration_deinit(). For resources allocated in vfio_realize(), free them by jumping to de-register path in vfio_realize(). Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Fixes: a22651053b59 ("vfio: Make vfio-pci device migration capable") 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>
2023-07-10vfio/migration: Change vIOMMU blocker from global to per deviceZhenzhong Duan1-3/+4
Contrary to multiple device blocker which needs to consider already-attached devices to unblock/block dynamically, the vIOMMU migration blocker is a device specific config. Meaning it only needs to know whether the device is bypassing or not the vIOMMU (via machine property, or per pxb-pcie::bypass_iommu), and does not need the state of currently present devices. For this reason, the vIOMMU global migration blocker can be consolidated into the per-device migration blocker, allowing us to remove some unnecessary code. This change also makes vfio_mig_active() more accurate as it doesn't check for global blocker. Signed-off-by: Zhenzhong Duan <zhenzhong.duan@intel.com> Reviewed-by: Joao Martins <joao.m.martins@oracle.com> Reviewed-by: Cédric Le Goater <clg@redhat.com> Signed-off-by: Cédric Le Goater <clg@redhat.com>
2023-06-30vfio/migration: Make VFIO migration non-experimentalAvihai Horon1-26/+53
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>
2023-06-30vfio/migration: Reset bytes_transferred properlyAvihai Horon1-1/+5
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: 3710586caa5d ("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>
2023-06-30vfio/migration: Add support for switchover ack capabilityAvihai Horon1-1/+38
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>
2023-06-30vfio/migration: Add VFIO migration pre-copy supportAvihai Horon1-9/+156
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>
2023-06-30vfio/migration: Store VFIO migration flags in VFIOMigrationAvihai Horon1-0/+1
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>
2023-06-30vfio/migration: Refactor vfio_save_block() to return saved data sizeAvihai Horon1-8/+9
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>
2023-03-22*: Add missing includes of qemu/error-report.hRichard Henderson1-0/+1
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>
2023-03-07vfio/migration: Rename entry pointsAlex Williamson1-4/+4
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>
2023-03-07vfio/migration: Query device dirty page tracking supportJoao Martins1-0/+15
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>
2023-03-07vfio/migration: Block migration with vIOMMUJoao Martins1-0/+5
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>
2023-02-16vfio/migration: Remove VFIO migration protocol v1Avihai Horon1-678/+22
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>
2023-02-16vfio/migration: Implement VFIO migration protocol v2Avihai Horon1-37/+442
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>
2023-02-16vfio/migration: Rename functions/structs related to v1 protocolAvihai Horon1-51/+51
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>
2023-02-16vfio/migration: Move migration v1 logic to vfio_migration_init()Avihai Horon1-15/+15
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>
2023-02-16vfio/migration: Block multiple devices migrationAvihai Horon1-0/+6
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>
2023-02-16vfio/migration: Allow migration without VFIO IOMMU dirty tracking supportAvihai Horon1-2/+1
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>
2023-02-16vfio/migration: Fix NULL pointer dereference bugAvihai Horon1-1/+3
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: 02a7e71b1e5b ("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>
2023-02-15migration: Rename res_{postcopy,precopy}_onlyJuan Quintela1-6/+4
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>
2023-02-15migration: Remove unused res_compatibleJuan Quintela1-2/+1
Nothing assigns to it after previous commit. Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Signed-off-by: Juan Quintela <quintela@redhat.com>
2023-02-06migration: Remove unused threshold_size parameterJuan Quintela1-1/+0
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>
2023-02-06migration: Split save_live_pending() into state_pending_*Juan Quintela1-10/+11
We split the function into to: - state_pending_estimate: We estimate the remaining state size without stopping the machine. - state pending_exact: We calculate the exact amount of remaining state. The only "device" that implements different functions for _estimate() and _exact() is ram. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2023-02-06migration: No save_live_pending() method uses the QEMUFile parameterJuan Quintela1-1/+1
So remove it everywhere. Signed-off-by: Juan Quintela <quintela@redhat.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2022-11-03vfio/migration: Fix wrong enum usageAvihai Horon1-1/+1
vfio_migration_init() initializes VFIOMigration->device_state using enum of VFIO migration protocol v2. Current implemented protocol is v1 so v1 enum should be used. Fix it. Fixes: 429c72800654 ("vfio/migration: Fix incorrect initialization value for parameters in VFIOMigration") Signed-off-by: Avihai Horon <avihaih@nvidia.com> Reviewed-by: Zhang Chen <chen.zhang@intel.com> Link: https://lore.kernel.org/r/20221016085752.32740-1-avihaih@nvidia.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-09-27vfio/migration: Fix incorrect initialization value for parameters in ↵Kunkun Jiang1-0/+2
VFIOMigration The structure VFIOMigration of a VFIODevice is allocated and initialized in vfio_migration_init(). "device_state" and "vm_running" are initialized to 0, indicating that VFIO device is_STOP and VM is not-running. The initialization value is incorrect. According to the agreement, default state of VFIO device is _RUNNING. And if a VFIO device is hot-plugged while the VM is running, "vm_running" should be 1. This patch fixes it. Fixes: 02a7e71b1e5b ("vfio: Add VM state change handler to know state of VM") Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> Link: https://lore.kernel.org/r/20220711014651.1327-1-jiangkunkun@huawei.com Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2022-05-13linux-headers: Update to v5.18-rc6Alex Williamson1-12/+15
Update to c5eb0a61238d ("Linux 5.18-rc6"). Mechanical search and replace of vfio defines with white space massaging. Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-08-26vfio: Avoid error_propagate() after migrate_add_blocker()Markus Armbruster1-4/+2
When migrate_add_blocker(blocker, &err) is followed by error_propagate(errp, err), we can often just as well do migrate_add_blocker(..., errp). This is the case in vfio_migration_probe(). Prior art: commit 386f6c07d2 "error: Avoid error_propagate() after migrate_add_blocker()". Cc: Kirti Wankhede <kwankhede@nvidia.com> Cc: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Markus Armbruster <armbru@redhat.com> Message-Id: <20210720125408.387910-8-armbru@redhat.com> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed by: Kirti Wankhede <kwankhede@nvidia.com> Acked-by: Michael S. Tsirkin <mst@redhat.com>
2021-06-18vfio/migration: Correct device state from vmstate change for savevm caseKirti Wankhede1-1/+10
Set _SAVING flag for device state from vmstate change handler when it gets called from savevm. Currently State transition savevm/suspend is seen as: _RUNNING -> _STOP -> Stop-and-copy -> _STOP State transition savevm/suspend should be: _RUNNING -> Stop-and-copy -> _STOP State transition from _RUNNING to _STOP occurs from vfio_vmstate_change() where when vmstate changes from running to !running, _RUNNING flag is reset but at the same time when vfio_vmstate_change() is called for RUN_STATE_SAVE_VM, _SAVING bit should be set. Reported by: Yishai Hadas <yishaih@nvidia.com> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Message-Id: <1623177441-27496-1-git-send-email-kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-06-18vfio: Fix unregister SaveVMHandler in vfio_migration_finalizeKunkun Jiang1-0/+1
In the vfio_migration_init(), the SaveVMHandler is registered for VFIO device. But it lacks the operation of 'unregister'. It will lead to 'Segmentation fault (core dumped)' in qemu_savevm_state_setup(), if performing live migration after a VFIO device is hot deleted. Fixes: 7c2f5f75f94 (vfio: Register SaveVMHandlers for VFIO device) Reported-by: Qixin Gan <ganqixin@huawei.com> Signed-off-by: Kunkun Jiang <jiangkunkun@huawei.com> Message-Id: <20210527123101.289-1-jiangkunkun@huawei.com> Reviewed by: Kirti Wankhede <kwankhede@nvidia.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-05-02Do not include cpu.h if it's not really necessaryThomas Huth1-1/+0
Stop including cpu.h in files that don't need it. Signed-off-by: Thomas Huth <thuth@redhat.com> Message-Id: <20210416171314.2074665-4-thuth@redhat.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2021-03-16vfio/migrate: Move switch of dirty tracking into vfio_memory_listenerKeqian Zhu1-35/+0
For now the switch of vfio dirty page tracking is integrated into @vfio_save_handler. The reason is that some PCI vendor driver may start to track dirty base on _SAVING state of device, so if dirty tracking is started before setting device state, vfio will report full-dirty to QEMU. However, the dirty bmap of all ramblocks are fully set when setup ram saving, so it's not matter whether the device is in _SAVING state when start vfio dirty tracking. Moreover, this logic causes some problems [1]. The object of dirty tracking is guest memory, but the object of @vfio_save_handler is device state, which produces unnecessary coupling and conflicts: 1. Coupling: Their saving granule is different (perVM vs perDevice). vfio will enable dirty_page_tracking for each devices, actually once is enough. 2. Conflicts: The ram_save_setup() traverses all memory_listeners to execute their log_start() and log_sync() hooks to get the first round dirty bitmap, which is used by the bulk stage of ram saving. However, as vfio dirty tracking is not yet started, it can't get dirty bitmap from vfio. Then we give up the chance to handle vfio dirty page at bulk stage. Move the switch of vfio dirty_page_tracking into vfio_memory_listener can solve above problems. Besides, Do not require devices in SAVING state for vfio_sync_dirty_bitmap(). [1] https://www.spinics.net/lists/kvm/msg229967.html Reported-by: Zenghui Yu <yuzenghui@huawei.com> Signed-off-by: Keqian Zhu <zhukeqian1@huawei.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Message-Id: <20210309031913.11508-1-zhukeqian1@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-03-16vfio: Set the priority of the VFIO VM state change handler explicitlyShenming Lu1-1/+2
In the VFIO VM state change handler when stopping the VM, the _RUNNING bit in device_state is cleared which makes the VFIO device stop, including no longer generating interrupts. Then we can save the pending states of all interrupts in the GIC VM state change handler (on ARM). So we have to set the priority of the VFIO VM state change handler explicitly (like virtio devices) to ensure it is called before the GIC's in saving. Signed-off-by: Shenming Lu <lushenming@huawei.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20210310030233.1133-3-lushenming@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-03-16vfio: Move the saving of the config space to the right place in VFIO migrationShenming Lu1-10/+15
On ARM64 the VFIO SET_IRQS ioctl is dependent on the VM interrupt setup, if the restoring of the VFIO PCI device config space is before the VGIC, an error might occur in the kernel. So we move the saving of the config space to the non-iterable process, thus it will be called after the VGIC according to their priorities. As for the possible dependence of the device specific migration data on it's config space, we can let the vendor driver to include any config info it needs in its own data stream. Signed-off-by: Shenming Lu <lushenming@huawei.com> Reviewed-by: Kirti Wankhede <kwankhede@nvidia.com> Message-Id: <20210310030233.1133-2-lushenming@huawei.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2021-03-09sysemu: Let VMChangeStateHandler take boolean 'running' argumentPhilippe Mathieu-Daudé1-1/+1
The 'running' argument from VMChangeStateHandler does not require other value than 0 / 1. Make it a plain boolean. Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Acked-by: David Gibson <david@gibson.dropbear.id.au> Message-Id: <20210111152020.1422021-3-philmd@redhat.com> Signed-off-by: Laurent Vivier <laurent@vivier.eu>
2020-11-23vfio: Make migration support experimentalAlex Williamson1-1/+1
Support for migration of vfio devices is still in flux. Developers are attempting to add support for new devices and new architectures, but none are yet readily available for validation. We have concerns whether we're transferring device resources at the right point in the migration, whether we're guaranteeing that updates during pre-copy are migrated, and whether we can provide bit-stream compatibility should any of this change. Even the question of whether devices should participate in dirty page tracking during pre-copy seems contentious. In short, migration support has not had enough soak time and it feels premature to mark it as supported. Create an experimental option such that we can continue to develop. [Retaining previous acks/reviews for a previously identical code change with different specifics in the commit log.] Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-12Fix use after free in vfio_migration_probeKirti Wankhede1-1/+1
Fixes Coverity issue: CID 1436126: Memory - illegal accesses (USE_AFTER_FREE) Fixes: a9e271ec9b36 ("vfio: Add migration region initialization and finalize function") Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: David Edmondson <dme@dme.org> Reviewed-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01qapi: Add VFIO devices migration stats in Migration statsKirti Wankhede1-0/+9
Added amount of bytes transferred to the VM at destination by all VFIO devices Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01vfio: Add function to start and stop dirty pages trackingKirti Wankhede1-0/+36
Call VFIO_IOMMU_DIRTY_PAGES ioctl to start and stop dirty pages tracking for VFIO devices. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01vfio: Get migration capability flags for containerKirti Wankhede1-1/+6
Added helper functions to get IOMMU info capability chain. Added function to get migration capability information from that capability chain for IOMMU container. Similar change was proposed earlier: https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg03759.html Disable migration for devices if IOMMU module doesn't support migration capability. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Cc: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com> Cc: Eric Auger <eric.auger@redhat.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01vfio: Add load state functions to SaveVMHandlersKirti Wankhede1-0/+195
Sequence during _RESUMING device state: While data for this device is available, repeat below steps: a. read data_offset from where user application should write data. b. write data of data_size to migration region from data_offset. c. write data_size which indicates vendor driver that data is written in staging buffer. For user, data is opaque. User should write data in the same order as received. Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Neo Jia <cjia@nvidia.com> Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
2020-11-01vfio: Add save state functions to SaveVMHandlersKirti Wankhede1-0/+276
Added .save_live_pending, .save_live_iterate and .save_live_complete_precopy functions. These functions handles pre-copy and stop-and-copy phase. In _SAVING|_RUNNING device state or pre-copy phase: - read pending_bytes. If pending_bytes > 0, go through below steps. - read data_offset - indicates kernel driver to write data to staging buffer. - read data_size - amount of data in bytes written by vendor driver in migration region. - read data_size bytes of data from data_offset in the migration region. - Write data packet to file stream as below: {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data, VFIO_MIG_FLAG_END_OF_STATE } In _SAVING device state or stop-and-copy phase a. read config space of device and save to migration file stream. This doesn't need to be from vendor driver. Any other special config state from driver can be saved as data in following iteration. b. read pending_bytes. If pending_bytes > 0, go through below steps. c. read data_offset - indicates kernel driver to write data to staging buffer. d. read data_size - amount of data in bytes written by vendor driver in migration region. e. read data_size bytes of data from data_offset in the migration region. f. Write data packet as below: {VFIO_MIG_FLAG_DEV_DATA_STATE, data_size, actual data} g. iterate through steps b to f while (pending_bytes > 0) h. Write {VFIO_MIG_FLAG_END_OF_STATE} When data region is mapped, its user's responsibility to read data from data_offset of data_size before moving to next steps. Added fix suggested by Artem Polyakov to reset pending_bytes in vfio_save_iterate(). Added fix suggested by Zhi Wang to add 0 as data size in migration stream and add END_OF_STATE delimiter to indicate phase complete. Suggested-by: Artem Polyakov <artemp@nvidia.com> Suggested-by: Zhi Wang <zhi.wang.linux@gmail.com> Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> Reviewed-by: Neo Jia <cjia@nvidia.com> Reviewed-by: Yan Zhao <yan.y.zhao@intel.com> Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
generated by cgit v1.1 at 2025-04-03 11:50:42 +0000