qemu/qemu.git/migration/options.h, branch master

migration/rdma: add x-rdma-chunk-size parameter

2026-05-05T16:35:24+00:00

The default 1MB RDMA chunk size causes slow live migration because each chunk triggers a write_flush (ibv_post_send). For 8GB RAM, 1MB chunk size produces ~15000 flushes vs ~3700 with 1024MB chunk size. Add x-rdma-chunk-size parameter to configure the RDMA chunk size for faster migration. Usage: `migrate_set_parameter x-rdma-chunk-size 1024M` Performance with RDMA live migration of 8GB RAM VM: | x-rdma-chunk-size (B) | time (s) | throughput (MB/s) | |-----------------------|----------|-------------------| | 1M (default) | 37.915 | 1,007 | | 32M | 17.880 | 2,260 | | 1024M | 4.368 | 17,529 | Signed-off-by: Samuel Zhang Acked-by: Markus Armbruster Acked-by: Li Zhijian Tested-by: Li Zhijian Acked-by: Fabiano Rosas Acked-by: Peter Xu Link: https://lore.kernel.org/r/20260427031401.3895523-1-guoqing.zhang@amd.com Signed-off-by: Peter Xu

Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging

2025-12-28T22:10:40+00:00

* cleanup include/hw headers * cleanup memory headers * rust: preludes * rust: support for dtrace * rust/hpet: first part of reorganization * meson: small cleanups * target/i386: Diamond Rapids CPU model including CET, APX, AVX10.2 # -----BEGIN PGP SIGNATURE----- # # iQFIBAABCgAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmlPov8UHHBib256aW5p # QHJlZGhhdC5jb20ACgkQv/vSX3jHroPN1wf9HCceQ1273g7HbNeamay2bSaqypyM # sEUBk4ipwO0dp7AYaaX5MeJ8NxeYcK82oFgm35WLY1tMOv0BZG5ez02dLoh5C4fb # Bmy3kV1aY9cxF0IwTyD4dIADlZoaMnGgMElUKFY2/EixjxOUMLe90b1MO2KczqFa # jvC4gmjx5PC1r+BHycSEdKm2Rbunueb/5eSkKeyTX7rjxQ/Eij0uGjrWrZkMWtgs # ERJ2xo+D6a38w/uJ88KuqUV1BqYxNNwKmvOwVBU2xFB9o9bm20TNOJZ3+D+Ki8Aj # idv+rU0XY1bWseo4USuozsqxfkjLJ5lj2YYUkSVO/I1wJmuO7Bq6xzrCxg== # =/nIt # -----END PGP SIGNATURE----- # gpg: Signature made Sat 27 Dec 2025 08:12:31 PM AEDT # gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83 # gpg: issuer "pbonzini@redhat.com" # gpg: Good signature from "Paolo Bonzini " [unknown] # gpg: aka "Paolo Bonzini " [unknown] # gpg: WARNING: The key's User ID is not certified with a trusted signature! # gpg: There is no indication that the signature belongs to the owner. # Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1 # Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83 * tag 'for-upstream' of https://gitlab.com/bonzini/qemu: (152 commits) block: rename block/aio-wait.h to qemu/aio-wait.h block: rename block/aio.h to qemu/aio.h block: reduce files included by block/aio.h block: extract include/qemu/aiocb.h out of include/block/aio.h hw: add missing includes hidden by block/aio.h qmp: Fix thread race thread-pool: Fix thread race dosc/cpu-models-x86: Add documentation for DiamondRapids i386/cpu: Add CPU model for Diamond Rapids i386/cpu: Define dependency for VMX_VM_ENTRY_LOAD_IA32_FRED i386/cpu: Add an option in X86CPUDefinition to control CPUID 0x1f i386/cpu: Allow cache to be shared at thread level i386/cpu: Allow unsupported avx10_version with x-force-features i386/cpu: Add a helper to get host avx10 version i386/cpu: Support AVX10.2 with AVX10 feature models i386/cpu: Add support for AVX10_VNNI_INT in CPUID enumeration i386/cpu: Add CPUID.0x1E.0x1 subleaf for AMX instructions i386/cpu: Add support for MOVRS in CPUID enumeration run: introduce a script for running devel commands gitlab-ci: enable rust for msys2-64bit ... Signed-off-by: Richard Henderson

include: move hw/qdev-properties-system.h to hw/core/

2025-12-27T09:11:08+00:00

Signed-off-by: Paolo Bonzini

include: move hw/qdev-properties.h to hw/core/

2025-12-27T09:11:07+00:00

Signed-off-by: Paolo Bonzini

migration: Normalize tls arguments

2025-12-23T14:24:34+00:00

The migration parameters tls_creds, tls_authz and tls_hostname currently have a non-uniform handling. When used as arguments to migrate-set-parameters, their type is StrOrNull and when used as return value from query-migrate-parameters their type is a plain string. Not only having to convert between the types is cumbersome, but it also creates the issue of requiring two different QAPI types to be used, one for each command. MigrateSetParameters is used for migrate-set-parameters with the TLS arguments as StrOrNull while MigrationParameters is used for query-migrate-parameters with the TLS arguments as str. Since StrOrNull could be considered a superset of str, change the type of the TLS arguments in MigrationParameters to StrOrNull. Also ensure that QTYPE_QNULL is never used. 1) migrate-set-parameters will always write QTYPE_QSTRING to s->parameters, either an empty or non-empty string. 2) query-migrate-parameters will always return a QTYPE_QSTRING, either empty or non-empty. 3) the migrate_tls_* helpers will always return a non-empty string or NULL, for the internal migration code's consumption. Points (1) and (2) above help simplify the parameters validation and the query command handling because s->parameters is already kept in the format that query-migrate-parameters (and info migrate_paramters) expect. Point (3) is so people don't need to care about StrOrNull in migration code. This will allow the type duplication to be removed in the next patches. Note that the type of @tls_creds, @tls-hostname, @tls-authz changes from str to StrOrNull in introspection of the query-migrate-parameters command. We accept this imprecision to enable de-duplication. There's no need to free the TLS options in migration_instance_finalize() because they're freed by the qdev properties .release method. Temporary in this patch: migrate_params_test_apply() copies s->parameters into a temporary structure, so it's necessary to drop the references to the TLS options if they were not set by the user to avoid double-free. This is fixed in the next patches. Acked-by: Markus Armbruster Signed-off-by: Fabiano Rosas Link: https://lore.kernel.org/r/20251215220041.12657-6-farosas@suse.de [peterx: in hmp_info_migrate_parameters(), remove an extra dump of max_postcopy_bandwidth, introduced likely by accident] Signed-off-by: Peter Xu

migration/savevm: Add a compatibility check for capabilities

2025-11-03T21:04:09+00:00

It has always been possible to enable arbitrary migration capabilities and attempt to take a snapshot of the VM with the savevm/loadvm commands as well as their QMP counterparts snapshot-save/snapshot-load. Most migration capabilities are not meant to be used with snapshots and there's a risk of crashing QEMU or producing incorrect behavior. Ideally, every migration capability would either be implemented for savevm or explicitly rejected. Add a compatibility check routine and reject the snapshot command if an incompatible capability is enabled. For now only act on the the two that actually cause a crash: multifd and mapped-ram. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2881 Signed-off-by: Fabiano Rosas Link: https://lore.kernel.org/r/20251007184213.5990-1-farosas@suse.de Signed-off-by: Peter Xu

migration: check RDMA and capabilities are compatible on both sides

2025-05-02T15:09:36+00:00

Depending on the order of starting RDMA and setting capability, they can be categorized into the following scenarios: Source: S1: [set capabilities] -> [Start RDMA outgoing] Destination: D1: [set capabilities] -> [Start RDMA incoming] D2: [Start RDMA incoming] -> [set capabilities] Previously, compatibility between RDMA and capabilities was verified only in scenario D1, potentially causing migration failures in other situations. For scenarios S1 and D1, we can seamlessly incorporate migration_transport_compatible() to address compatibility between channels and capabilities vs transport. For scenario D2, ensure compatibility within migrate_caps_check(). Reviewed-by: Peter Xu Signed-off-by: Li Zhijian Message-ID: <20250305062825.772629-3-lizhijian@fujitsu.com> Signed-off-by: Fabiano Rosas

migration: Use device_class_set_props_n

2024-12-19T18:33:37+00:00

Export the migration_properties array size from options.c; use that to feed device_class_set_props_n. We must remove DEFINE_PROP_END_OF_LIST so the count is correct. Signed-off-by: Richard Henderson Tested-by: Lei Yang Link: https://lore.kernel.org/r/20241218134251.4724-15-richard.henderson@linaro.org Signed-off-by: Paolo Bonzini

migration: Constify migration_properties

2024-12-19T18:33:37+00:00

Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Tested-by: Lei Yang Link: https://lore.kernel.org/r/20241218134251.4724-2-richard.henderson@linaro.org Signed-off-by: Paolo Bonzini

migration: Remove unused migrate_zero_blocks

2024-10-08T19:28:55+00:00

migrate_zero_blocks is unused since eef0bae3a7 ("migration: Remove block migration") Remove it. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Peter Xu Link: https://lore.kernel.org/r/20240919134626.166183-3-dave@treblig.org Signed-off-by: Peter Xu