Use the return-path capability with colo and reuse the opened return path
file on both primary and secondary side.
This fixes a crash in colo where migration_cancel() races with colo closing
s->rp_state.from_dst_file.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20260302-colo_unit_test_multifd-v11-21-d653fb3b1d80@web.de
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The TLS hostname is doing a tour around the world just to be cached
into s->hostname. We're already abusing MigrationState by doing that,
so incorporate the s->hostname into migration_tls_hostname() and stop
passing the string around.
The old route was roughly:
-transport code (socket.c, fd.c, etc):
if (SOCKET_ADDRESS_TYPE_INET)
hostname = saddr->u.inet.host
else
hostname = NULL
migration_channel_connect(..., hostname)
s->hostname = hostname;
migration_tls_client_create(..., hostname)
if (migrate_tls_hostname())
qio_channel_tls_new_client(migrate_tls_hostname())
else
qio_channel_tls_new_client(hostname)
-postcopy_preempt_setup:
postcopy_preempt_send_channel_new
migration_tls_client_create(..., s->hostname)
New route is:
-socket.c only:
if SOCKET_ADDRESS_TYPE_INET
s->hostname = saddr->u.inet.host
migration_channel_connect()
migration_tls_client_create()
qio_channel_tls_new_client(migrate_tls_hostname())
-postcopy_preempt_setup:
postcopy_preempt_send_channel_new
migration_tls_client_create()
qio_channel_tls_new_client(migrate_tls_hostname())
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Prasad Pandit <pjp@fedoraproject.org>
Link: https://lore.kernel.org/qemu-devel/20260123141656.6765-5-farosas@suse.de
Signed-off-by: Fabiano Rosas <farosas@suse.de>
It was declared deprecated since 9.2.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/qemu-devel/20260115225503.3083355-2-peterx@redhat.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
QAPI_CLONE_MEMBERS is a better option than copying parameters one by
one because it operates on the entire struct and follows pointers. It
also avoids the need to alter this function every time a new parameter
is added.
For this to work, the has_* fields of s->parameters need to be already
set beforehand, so move migrate_mark_all_params_present() to the init
routine.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-14-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
MigrationParameters needs to have all of its has_* fields marked as
true when used as the return of query_migrate_parameters because the
corresponding QMP command has all of its members non-optional by
design, despite them being marked as optional in migration.json.
Extract this code into a function and make it assert if any field is
missing. With this we ensure future changes will not inadvertently
leave any parameters missing.
Note that the block-bitmap-mapping is a special case because the empty
list is considered a valid value, so it has historically not been
present in the command's output if it has never been set.
CC: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-13-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
The QERR_INVALID_PARAMETER_VALUE macro is documented as not to be used
in new code. Remove the usage from migration/options.c.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-12-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
The migration parameters validation produces a temporary structure
which is the merge of the current parameter values (s->parameters,
MigrationParameters) with the new parameters set by the user
(former MigrateSetParameters).
When copying the values from s->parameters into the temporary
structure, the has_* fields are copied along, but when merging the
user-input values they are not.
During migrate_params_check(), only the parameters that have the
corresponding has_* field will be checked, so only the parameters that
were initialized in migrate_params_init() will be validated.
This causes (almost) all of the migration parameters to be validated
every time a parameter is set, regardless of which fields the user
touched, but it also skips validation of any values that are not set
in migrate_params_init().
It's not clear what was the intention of the original code, whether to
validate all fields always, or only validate what the user input
changed. Since the current situation is closer to the former option,
make the choice of validating all parameters by removing the checks
for the has_* fields when validating.
Note that bringing the user input into the temporary structure for
validation still needs to look at the has_* fields, otherwise any
parameters not set by the user (i.e. 0) would override the
corresponding value in s->parameters.
The empty migrate_params_init() will be kept because subsequent
patches will add code to it.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-11-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
The QAPI converts an empty list on the block-bitmap-mapping input into
a NULL BitmapMigrationNodeAliasList. The empty list is a valid input
for the block-bitmap-mapping option, so commit 3cba22c9ad ("migration:
Fix block_bitmap_mapping migration") started using the
s->parameters.has_block_bitmap_mapping field to tell when the user has
passed in an empty list vs. when no list has been passed at all.
Using s->parameters.has_block_bitmap_mapping field is only possible
because MigrationParameters has had its members made optional due to
historical reasons.
In order to make improvements to the way configuration options are set
for a migration, we'd like to reduce the open-coded usage of the has_*
fields of the global configuration object (s->parameters).
Add a separate boolean to track the status of the block_bitmap_mapping
option.
No functional change intended.
(this was verified to not regress iotest 300, which is the test that
3cba22c9ad refers to)
CC: Kevin Wolf <kwolf@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-10-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Some migration parameters are updated immediately once they are set
via migrate-set-parameters. Move that work outside of
migrate_params_apply() and leave that function with the single
responsibility of setting s->parameters and not doing any
side-effects.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-9-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Now that the TLS options have been made the same between
migrate-set-parameters and query-migrate-parameters, a single type can
be used. Remove MigrateSetParameters.
The TLS options documentation from MigrationParameters were replaced
with the ones from MigrateSetParameters which was more complete.
Acked-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251215220041.12657-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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 <armbru@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
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 <peterx@redhat.com>
The MigrationState is a QOM object with TYPE_DEVICE as a parent. This
was done about eight years ago so the migration code could make use of
qdev properties to define the defaults for the migration parameters
and to be able to expose migration knobs for debugging via the
'-global migration' command line option.
Due to unrelated historical reasons, three of the migration parameters
(TLS options) received different types when used via the
query-migrate-parameters QMP command than with the
migrate-set-parameters command. This has created a lot of duplication
in the migration code and in the QAPI documentation because the whole
of MigrationParameters had to be duplicated as well.
The migration code is now being fixed to remove the duplication and
for that to happen the offending fields need to be reconciled into a
single type. The StrOrNull type is going to be used.
To keep the command line compatibility, the parameters need to
continue being exposed via qdev properties accessible from the command
line. Introduce a qdev property StrOrNull just for that.
Note that this code is being kept in migration/options.c as this
version of StrOrNull doesn't need to handle QNULL because it was never
a valid option in the previous command line, which took a string.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Acked-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20251215220041.12657-4-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
This aids scriptings only.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20251205172054.288909-1-peterx@redhat.com
[peterx: make the property x-ignore-shared to match, per cedric]
[peterx: fix over-80 line]
Signed-off-by: Peter Xu <peterx@redhat.com>
Make mapped-ram compatible with loadvm snapshot restoring by explicitly
zeroing memory pages in this case.
Skip zeroing for -incoming and -loadvm migrations to preserve performance.
Signed-off-by: Marco Cavenati <Marco.Cavenati@eurecom.fr>
Link: https://lore.kernel.org/r/20251010115954.1995298-3-Marco.Cavenati@eurecom.fr
Signed-off-by: Peter Xu <peterx@redhat.com>
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 <farosas@suse.de>
Link: https://lore.kernel.org/r/20251007184213.5990-1-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Create the cpr-exec-command migration parameter, defined as a list of
strings. It will be used for cpr-exec migration mode in a subsequent
patch, and contains forward references to cpr-exec mode in the qapi
doc.
No functional change, except that cpr-exec-command is shown by the
'info migrate' command.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/1759332851-370353-5-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
With commit 82137e6c8c ("migration: enforce multifd and postcopy preempt to
be set before incoming"), and if postcopy preempt / multifd is enabled, one
cannot setup any capability because these checks would always fail.
(qemu) migrate_set_capability xbzrle off
Error: Postcopy preempt must be set before incoming starts
To fix it, check existing cap and only raise an error if the specific cap
changed.
Fixes: 82137e6c8c ("migration: enforce multifd and postcopy preempt to be set before incoming")
Reviewed-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Juraj Marcin <jmarcin@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Enable Multifd and Postcopy migration together.
The migration_ioc_process_incoming() routine checks
magic value sent on each channel and helps to properly
setup multifd and postcopy channels.
The Precopy and Multifd threads work during the initial
guest RAM transfer. When migration moves to the Postcopy
phase, the multifd threads cease to send data on multifd
channels and Postcopy threads on the destination
request/pull data from the source side.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Prasad Pandit <pjp@fedoraproject.org>
Link: https://lore.kernel.org/r/20250512125124.147064-3-ppandit@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
It's believed that RDMA + postcopy-ram has been broken for a while.
Rather than spending time re-enabling it, let's simply disable it as a
trade-off.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Message-ID: <20250305062825.772629-4-lizhijian@fujitsu.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
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 <peterx@redhat.com>
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Message-ID: <20250305062825.772629-3-lizhijian@fujitsu.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
This QEMU_VM_COMMAND sub-command and its switchover_start SaveVMHandler is
used to mark the switchover point in main migration stream.
It can be used to inform the destination that all pre-switchover main
migration stream data has been sent/received so it can start to process
post-switchover data that it might have received via other migration
channels like the multifd ones.
Add also the relevant MigrationState bit stream compatibility property and
its hw_compat entry.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Zhang Chen <zhangckid@gmail.com> # for the COLO part
Signed-off-by: Maciej S. Szmigiero <maciej.szmigiero@oracle.com>
Link: https://lore.kernel.org/qemu-devel/311be6da85fc7e49a7598684d80aa631778dcbce.1741124640.git.maciej.szmigiero@oracle.com
Signed-off-by: Cédric Le Goater <clg@redhat.com>
We're currently changing the way the source multifd migration handles
the shutdown of the multifd channels when TLS is in use to perform a
clean termination by calling gnutls_bye().
Older src QEMUs will always close the channel without terminating the
TLS session. New dst QEMUs treat an unclean termination as an error.
Add multifd_clean_tls_termination (default true) that can be switched
on the destination whenever a src QEMU <= 9.2 is in use.
(Note that the compat property is only strictly necessary for src
QEMUs older than 9.1. Due to synchronization coincidences, src QEMUs
9.1 and 9.2 can put the destination in a condition where it doesn't
see the unclean termination. Still, make the property more inclusive
to facilitate potential backports.)
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The general expectation is that header files should follow the same
file/path naming scheme as the corresponding source file. There are
various historical exceptions to this practice in QEMU, with one of
the most notable being the include/qapi/qmp/ directory. Most of the
headers there correspond to source files in qobject/.
This patch corrects most of that inconsistency by creating
include/qobject/ and moving the headers for qobject/ there.
This also fixes MAINTAINERS for include/qapi/qmp/dispatch.h:
scripts/get_maintainer.pl now reports "QAPI" instead of "No
maintainers found".
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Acked-by: Halil Pasic <pasic@linux.ibm.com> #s390x
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20241118151235.2665921-2-armbru@redhat.com>
[Rebased]
Add the cpr-transfer migration mode, which allows the user to transfer
a guest to a new QEMU instance on the same host with minimal guest pause
time, by preserving guest RAM in place, albeit with new virtual addresses
in new QEMU, and by preserving device file descriptors. Pages that were
locked in memory for DMA in old QEMU remain locked in new QEMU, because the
descriptor of the device that locked them remains open.
cpr-transfer preserves memory and devices descriptors by sending them to
new QEMU over a unix domain socket using SCM_RIGHTS. Such CPR state cannot
be sent over the normal migration channel, because devices and backends
are created prior to reading the channel, so this mode sends CPR state
over a second "cpr" migration channel. New QEMU reads the cpr channel
prior to creating devices or backends. The user specifies the cpr channel
in the channel arguments on the outgoing side, and in a second -incoming
command-line parameter on the incoming side.
The user must start old QEMU with the the '-machine aux-ram-share=on' option,
which allows anonymous memory to be transferred in place to the new process
by transferring a memory descriptor for each ram block. Memory-backend
objects must have the share=on attribute, but memory-backend-epc is not
supported.
The user starts new QEMU on the same host as old QEMU, with command-line
arguments to create the same machine, plus the -incoming option for the
main migration channel, like normal live migration. In addition, the user
adds a second -incoming option with channel type "cpr". This CPR channel
must support file descriptor transfer with SCM_RIGHTS, i.e. it must be a
UNIX domain socket.
To initiate CPR, the user issues a migrate command to old QEMU, adding
a second migration channel of type "cpr" in the channels argument.
Old QEMU stops the VM, saves state to the migration channels, and enters
the postmigrate state. New QEMU mmap's memory descriptors, and execution
resumes.
The implementation splits qmp_migrate into start and finish functions.
Start sends CPR state to new QEMU, which responds by closing the CPR
channel. Old QEMU detects the HUP then calls finish, which connects the
main migration channel.
In summary, the usage is:
qemu-system-$arch -machine aux-ram-share=on ...
start new QEMU with "-incoming <main-uri> -incoming <cpr-channel>"
Issue commands to old QEMU:
migrate_set_parameter mode cpr-transfer
{"execute": "migrate", ...
{"channel-type": "main"...}, {"channel-type": "cpr"...} ... }
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/1736967650-129648-17-git-send-email-steven.sistare@oracle.com
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Headers in include/sysemu/ are not only related to system
*emulation*, they are also used by virtualization. Rename
as system/ which is clearer.
Files renamed manually then mechanical change using sed tool.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Message-Id: <20241203172445.28576-1-philmd@linaro.org>
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 <richard.henderson@linaro.org>
Tested-by: Lei Yang <leiyang@redhat.com>
Link: https://lore.kernel.org/r/20241218134251.4724-15-richard.henderson@linaro.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The zero-blocks capability was meant to be used along with the block
migration, which has been removed already in commit eef0bae3a7
("migration: Remove block migration").
Setting zero-blocks is currently a noop, but the outright removal of
the capability would cause and error in case some users are still
setting it. Put the capability through the deprecation process.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-4-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>
migrate_zero_blocks is unused since
eef0bae3a7 ("migration: Remove block migration")
Remove it.
Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240919134626.166183-3-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>
migrate_cap_set has been unused since
18d154f575 ("migration: Remove 'blk/-b' option from migrate commands")
Remove it.
Signed-off-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240919134626.166183-2-dave@treblig.org
Signed-off-by: Peter Xu <peterx@redhat.com>
Add the direct-io migration parameter that tells the migration code to
use O_DIRECT when opening the migration stream file whenever possible.
This is currently only used with the mapped-ram migration that has a
clear window guaranteed to perform aligned writes.
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The 'compress' migration capability enables the old compression code
which has shown issues over the years and is thought to be less stable
and tested than the more recent multifd-based compression. The old
compression code has been deprecated in 8.2 and now is time to remove
it.
Deprecation commit 864128df46 ("migration: Deprecate old compression
method").
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The block migration has been considered obsolete since QEMU 8.2 in
favor of the more flexible storage migration provided by the
blockdev-mirror driver. Two releases have passed so now it's time to
remove it.
Deprecation commit 66db46ca83 ("migration: Deprecate block
migration").
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The block migration is considered obsolete and has been deprecated in
8.2. Remove the migrate command option that enables it. This only
affects the QMP and HMP commands, the feature can still be accessed by
setting the migration 'block' capability. The whole feature will be
removed in a future patch.
Deprecation commit 8846b5bfca ("migration: migrate 'blk' command
option is deprecated.").
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
The block incremental option for block migration has been deprecated
in 8.2 in favor of using the block-mirror feature. Remove it now.
Deprecation commit 40101f320d ("migration: migrate 'inc' command
option is deprecated.").
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Address the comment added in commit 4629ed1e98
("qerror: Finally unused, clean up"), from 2015:
/*
* These macros will go away, please don't use
* in new code, and do not add new ones!
*/
Mechanical transformation using sed, manually
removing the definition in include/qapi/qmp/qerror.h.
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-10-armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
[Straightforward conflict with commit aeaafb1e59 (migration: export
migration_is_running) resolved]
QERR_INVALID_PARAMETER_VALUE is defined as:
#define QERR_INVALID_PARAMETER_VALUE \
"Parameter '%s' expects %s"
The current error is formatted as:
"Parameter 'vcpu_dirty_limit' expects is invalid, it must greater then 1 MB/s"
Replace by:
"Parameter 'vcpu_dirty_limit' must be greater than 1 MB/s"
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312141343.3168265-9-armbru@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
[New error message corrected, commit message updated accordingly]
Since the commit 05e385d2a9 ("error: Move ERRP_GUARD() to the beginning
of the function"), there are new codes that don't put ERRP_GUARD() at
the beginning of the functions.
As stated in the commit 05e385d2a9: "include/qapi/error.h advises to put
ERRP_GUARD() right at the beginning of the function, because only then
can it guard the whole function.", so clean up the few spots
disregarding the advice.
Inspired-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240312060337.3240965-1-zhao1.liu@linux.intel.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
As the comment in qapi/error, passing @errp to error_prepend() requires
ERRP_GUARD():
* = Why, when and how to use ERRP_GUARD() =
*
* Without ERRP_GUARD(), use of the @errp parameter is restricted:
...
* - It should not be passed to error_prepend(), error_vprepend() or
* error_append_hint(), because that doesn't work with &error_fatal.
* ERRP_GUARD() lifts these restrictions.
*
* To use ERRP_GUARD(), add it right at the beginning of the function.
* @errp can then be used without worrying about the argument being
* NULL or &error_fatal.
ERRP_GUARD() could avoid the case when @errp is &error_fatal, the user
can't see this additional information, because exit() happens in
error_setg earlier than information is added [1].
The migrate_params_check() passes @errp to error_prepend() without
ERRP_GUARD(), and it could be called from migration_object_init(),
where the passed @errp points to @error_fatal.
Therefore, the error message echoed in error_prepend() will be lost
because of the above issue.
To fix this, add missing ERRP_GUARD() at the beginning of this function.
[1]: Issue description in the commit message of commit ae7c80a7bd
("error: New macro ERRP_GUARD()").
Cc: Peter Xu <peterx@redhat.com>
Cc: Fabiano Rosas <farosas@suse.de>
Signed-off-by: Zhao Liu <zhao1.liu@intel.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Acked-by: Peter Xu <peterx@redhat.com>
Message-ID: <20240311033822.3142585-28-zhao1.liu@linux.intel.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
1. Set default "zero-page-detection" option to "multifd". Now
zero page checking can be done in the multifd threads and this
becomes the default configuration.
2. Handle migration QEMU9.0 -> QEMU8.2 compatibility. We provide
backward compatibility where zero page checking is done from the
migration main thread.
Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240311180015.3359271-7-hao.xiang@linux.dev
Signed-off-by: Peter Xu <peterx@redhat.com>
This new parameter controls where the zero page checking is running.
1. If this parameter is set to 'legacy', zero page checking is
done in the migration main thread.
2. If this parameter is set to 'none', zero page checking is disabled.
Signed-off-by: Hao Xiang <hao.xiang@bytedance.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Link: https://lore.kernel.org/r/20240311180015.3359271-4-hao.xiang@linux.dev
Signed-off-by: Peter Xu <peterx@redhat.com>
The new mapped-ram stream format uses a file transport and puts ram
pages in the migration file at their respective offsets and can be
done in parallel by using the pwritev system call which takes iovecs
and an offset.
Add support to enabling the new format along with multifd to make use
of the threading and page handling already in place.
This requires multifd to stop sending headers and leaving the stream
format to the mapped-ram code. When it comes time to write the data, we
need to call a version of qio_channel_write that can take an offset.
Usage on HMP is:
(qemu) stop
(qemu) migrate_set_capability multifd on
(qemu) migrate_set_capability mapped-ram on
(qemu) migrate_set_parameter max-bandwidth 0
(qemu) migrate_set_parameter multifd-channels 8
(qemu) migrate file:migfile
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240229153017.2221-21-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Add a new migration capability 'mapped-ram'.
The core of the feature is to ensure that RAM pages are mapped
directly to offsets in the resulting migration file instead of being
streamed at arbitrary points.
The reasons why we'd want such behavior are:
- The resulting file will have a bounded size, since pages which are
dirtied multiple times will always go to a fixed location in the
file, rather than constantly being added to a sequential
stream. This eliminates cases where a VM with, say, 1G of RAM can
result in a migration file that's 10s of GBs, provided that the
workload constantly redirties memory.
- It paves the way to implement O_DIRECT-enabled save/restore of the
migration stream as the pages are ensured to be written at aligned
offsets.
- It allows the usage of multifd so we can write RAM pages to the
migration file in parallel.
For now, enabling the capability has no effect. The next couple of
patches implement the core functionality.
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240229153017.2221-8-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
Some glue code was missing, so that using `qmp_migrate_set_parameters`
to set `multifd-zstd-level` or `multifd-zlib-level` did not work. This
commit adds the glue code to fix that.
Signed-off-by: Bryan Zhang <bryan.zhang@bytedance.com>
Link: https://lore.kernel.org/r/20240301035901.4006936-2-bryan.zhang@bytedance.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Coverity diagnoses a possible out-of-range array index here ...
static GSList *migration_blockers[MIG_MODE__MAX];
fill_source_migration_info() {
GSList *cur_blocker = migration_blockers[migrate_mode()];
... because it does not know that MIG_MODE__MAX will never be returned as
a migration mode. To fix, assert so in migrate_mode().
Fixes: fa3673e497 ("migration: per-mode blockers")
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/1699907025-215450-1-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Lukas Straub
Fabiano Rosas
Peter Xu
Marco Cavenati
Steve Sistare
Prasad Pandit
Markus Armbruster
Li Zhijian
Maciej S. Szmigiero
Daniel P. Berrangé
Philippe Mathieu-Daudé
Richard Henderson
Dr. David Alan Gilbert
Bryan Zhang
Zhao Liu
Hao Xiang