Delete the MigrationState parameter from migration_is_setup_or_active
and move it to the public API in misc.h.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Link: https://lore.kernel.org/r/1710179338-294359-3-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
A small number of migration options are accessed by migration clients,
but to see them clients must include all of options.h, which is mostly
for migration core code. migrate_mode() in particular will be needed by
multiple clients.
Refactor the option declarations so clients can see the necessary few via
misc.h, which already exports a portion of the client API.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Link: https://lore.kernel.org/r/1710179319-294320-1-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
The SaveVMHandlers structure is still in use for complex subsystems
and devices. Document the handlers since we are going to modify a few
later.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240304122844.1888308-9-clg@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
They are only used once.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20240304122844.1888308-8-clg@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Add utility methods that will be needed when implementing 'mapped-ram'
migration capability.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Link: https://lore.kernel.org/r/20240229153017.2221-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
When migration for cpr is initiated, stop the vm and set state
RUN_STATE_FINISH_MIGRATE before ram is saved. This eliminates the
possibility of ram and device state being out of sync, and guarantees
that a guest in the suspended state remains suspended, because qmp_cont
rejects a cont command in the RUN_STATE_FINISH_MIGRATE state.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-11-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Check the status returned by migration notifiers for event type
MIG_EVENT_PRECOPY_SETUP, and report errors. None of the notifiers
return an error status at this time.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-10-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Keep a separate list of migration notifiers for each migration mode.
Suggested-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-8-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Define MigrationNotifyFunc to improve type safety and simplify migration
notifiers.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-7-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Passing MigrationState to notifiers is unsound because they could access
unstable migration state internals or even modify the state. Instead, pass
the minimal info needed in a new MigrationEvent struct, which could be
extended in the future if needed.
Suggested-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-5-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Change all migration notifiers to type NotifierWithReturn, so notifiers
can return an error status in a future patch. For now, pass NULL for the
notifier error parameter, and do not check the return value.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-4-git-send-email-steven.sistare@oracle.com
[peterx: dropped unexpected update to roms/seabios-hppa]
Signed-off-by: Peter Xu <peterx@redhat.com>
Remove the error object from opaque data passed to notifiers.
Use the new error parameter passed to the notifier instead.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/1708622920-68779-3-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
The term "iothread lock" is obsolete. The APIs use Big QEMU Lock (BQL)
in their names. Update the code comments to use "BQL" instead of
"iothread lock".
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Message-id: 20240102153529.486531-5-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Restoring a snapshot can break a suspended guest. Snapshots suffer from
the same suspended-state issues that affect live migration, plus they must
handle an additional problematic scenario, which is that a running vm must
remain running if it loads a suspended snapshot.
To save, the existing vm_stop call now completely stops the suspended
state. Finish with vm_resume to leave the vm in the state it had prior
to the save, correctly restoring the suspended state.
To load, if the snapshot is not suspended, then vm_stop + vm_resume
correctly handles all states, and leaves the vm in the state it had prior
to the load. However, if the snapshot is suspended, restoration is
trickier. First, call vm_resume to restore the state to suspended so the
current state matches the saved state. Then, if the pre-load state is
running, call wakeup to resume running.
Prior to these changes, the vm_stop to RUN_STATE_SAVE_VM and
RUN_STATE_RESTORE_VM did not change runstate if the current state was
suspended, but now it does, so allow these transitions.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/1704312341-66640-8-git-send-email-steven.sistare@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Allow the array of pointers to itself be const.
Propagate this through the copies of this field.
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20231221031652.119827-2-richard.henderson@linaro.org>
Extend the blocker interface so that a blocker can be registered for
one or more migration modes. The existing interfaces register a
blocker for all modes, and the new interfaces take a varargs list
of modes.
Internally, maintain a separate blocker list per mode. The same Error
object may be added to multiple lists. When a block is deleted, it is
removed from every list, and the Error is freed.
No functional change until a new mode is added.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1698263069-406971-3-git-send-email-steven.sistare@oracle.com>
Create a mode migration parameter that can be used to select alternate
migration algorithms. The default mode is normal, representing the
current migration algorithm, and does not need to be explicitly set.
No functional change until a new mode is added, except that the mode is
shown by the 'info migrate' command.
Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <1698263069-406971-2-git-send-email-steven.sistare@oracle.com>
Current code does:
- register pre_2_10_vmstate_dummy_icp with "icp/server" and instance
dependinfg on cpu number
- for newer machines, it register vmstate_icp with "icp/server" name
and instance 0
- now it unregisters "icp/server" for the 1st instance.
This is wrong at many levels:
- we shouldn't have two VMSTATEDescriptions with the same name
- In case this is the only solution that we can came with, it needs to
be:
* register pre_2_10_vmstate_dummy_icp
* unregister pre_2_10_vmstate_dummy_icp
* register real vmstate_icp
Created vmstate_replace_hack_for_ppc() with warnings left and right
that it is a hack.
CC: Cedric Le Goater <clg@kaod.org>
CC: Daniel Henrique Barboza <danielhb413@gmail.com>
CC: David Gibson <david@gibson.dropbear.id.au>
CC: Greg Kurz <groug@kaod.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-8-quintela@redhat.com>
We have lots of cases where we are using an instance_id==0 when we
should be using VMSTATE_INSTANCE_ID_ANY (-1). Basically everything
that can have more than one needs to have a proper instance_id or -1
and the system will take one for it.
vmstate_register_any(): We register with -1.
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231020090731.28701-2-quintela@redhat.com>
The function is used on save at this point. The following commits will
use it on load.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231024084043.2926316-5-marcandre.lureau@redhat.com>
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>
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>
This is intended to be a semantic revert of commit 9b09503752
("migration: run setup callbacks out of big lock"). There have been so
many changes since that commit (e.g. a new setup callback
dirty_bitmap_save_setup() that also needs to be adapted now), it's
easier to do the revert manually.
For snapshots, the bdrv_writev_vmstate() function is used during setup
(in QIOChannelBlock backing the QEMUFile), but not holding the BQL
while calling it could lead to an assertion failure. To understand
how, first note the following:
1. Generated coroutine wrappers for block layer functions spawn the
coroutine and use AIO_WAIT_WHILE()/aio_poll() to wait for it.
2. If the host OS switches threads at an inconvenient time, it can
happen that a bottom half scheduled for the main thread's AioContext
is executed as part of a vCPU thread's aio_poll().
An example leading to the assertion failure is as follows:
main thread:
1. A snapshot-save QMP command gets issued.
2. snapshot_save_job_bh() is scheduled.
vCPU thread:
3. aio_poll() for the main thread's AioContext is called (e.g. when
the guest writes to a pflash device, as part of blk_pwrite which is a
generated coroutine wrapper).
4. snapshot_save_job_bh() is executed as part of aio_poll().
3. qemu_savevm_state() is called.
4. qemu_mutex_unlock_iothread() is called. Now
qemu_get_current_aio_context() returns 0x0.
5. bdrv_writev_vmstate() is executed during the usual savevm setup
via qemu_fflush(). But this function is a generated coroutine wrapper,
so it uses AIO_WAIT_WHILE. There, the assertion
assert(qemu_get_current_aio_context() == qemu_get_aio_context());
will fail.
To fix it, ensure that the BQL is held during setup. While it would
only be needed for snapshots, adapting migration too avoids additional
logic for conditional locking/unlocking in the setup callbacks.
Writing the header could (in theory) also trigger qemu_fflush() and
thus bdrv_writev_vmstate(), so the locked section also covers the
qemu_savevm_state_header() call, even for migration for consistency.
The section around multifd_send_sync_main() needs to be unlocked to
avoid a deadlock. In particular, the multifd_save_setup() function calls
socket_send_channel_create() using multifd_new_send_channel_async() as a
callback and then waits for the callback to signal via the
channels_ready semaphore. The connection happens via
qio_task_run_in_thread(), but the callback is only executed via
qio_task_thread_result() which is scheduled for the main event loop.
Without unlocking the section, the main thread would never get to
process the task result and the callback meaning there would be no
signal via the channels_ready semaphore.
The comment in ram_init_bitmaps() was introduced by 4987783400
("migration: fix incorrect memory_global_dirty_log_start outside BQL")
and is removed, because it referred to the qemu_mutex_lock_iothread()
call.
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231013105839.415989-1-f.ebner@proxmox.com>
Currently, a few code paths exist in the function vmstate_save_state_v,
which ultimately leads to a migration failure. However, an update in the
current MigrationState for the error description is never done.
vmstate.c somehow doesn't seem to allow the use of migrate_set_error due
to some dependencies for unit tests. Hence, this patch introduces a new
function vmstate_save_state_with_err, which will eventually propagate
the error message to savevm.c where a migrate_set_error call can be
eventually done.
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Tejus GK <tejus.gk@nutanix.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-ID: <20231003065538.244752-2-tejus.gk@nutanix.com>
Add a new .save_prepare() handler to struct SaveVMHandlers. This handler
is called early, even before migration starts, and can be used by
devices to perform early checks.
Refactor migrate_init() to be able to return errors and call
.save_prepare() from there.
Suggested-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Migration code can run both in coroutine context (the usual case) and
non-coroutine context (at least savevm/loadvm for snapshots). This also
affects the VMState callbacks, and devices must consider this. Change
the callback definition in VMStateInfo to be explicit about it.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20230905145002.46391-2-kwolf@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
virtio-mem wants to know whether it should not mess with the RAMBlock
content (e.g., discard RAM, preallocate memory) on incoming migration.
So let's expose that function as migrate_ram_is_ignored() in
migration/misc.h
Message-ID: <20230706075612.67404-4-david@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Tested-by: Mario Casquero <mcasquer@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Mention that QOM-ified devices already have support for registering
the description.
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230630180423.558337-24-alex.bennee@linaro.org>
Implement switchover ack logic. This prevents the source from stopping
the VM and completing the migration until an ACK is received from the
destination that it's OK to do so.
To achieve this, a new SaveVMHandlers handler switchover_ack_needed()
and a new return path message MIG_RP_MSG_SWITCHOVER_ACK are added.
The switchover_ack_needed() handler is called during migration setup in
the destination to check if switchover ack is used by the migrated
device.
When switchover is approved by all migrated devices in the destination
that support this capability, the MIG_RP_MSG_SWITCHOVER_ACK return path
message is sent to the source to notify it that it's OK to do
switchover.
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@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>
Actually global_state_store() can never fail. Let's get rid of extra
error paths.
To make things clear, use new runstate_get() and use same approach for
global_state_store() and global_state_store_running().
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230517123752.21615-3-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
These way we can make them atomic and use this functions from any
place. I also moved all functions that use rate_limit to
migration-stats.
Functions got renamed, they are not qemu_file anymore.
qemu_file_rate_limit -> migration_rate_exceeded
qemu_file_set_rate_limit -> migration_rate_set
qemu_file_get_rate_limit -> migration_rate_get
qemu_file_reset_rate_limit -> migration_rate_reset
qemu_file_acct_rate_limit -> migration_rate_account.
Reviewed-by: Harsh Prateek Bora <harshpb@linux.ibm.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230515195709.63843-6-quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Let's make better public interface for COLO: instead of
colo_process_incoming_thread and not trivial logic around creating the
thread let's make simple colo_incoming_co(), hiding implementation from
generic code.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230515130640.46035-4-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
colo_checkpoint_notify() is mostly used in colo.c. Outside we use it
once when x-checkpoint-delay migration parameter is set. So, let's
simplify the external API to only that function - notify COLO that
parameter was set. This make external API more robust and hides
implementation details from external callers. Also this helps us to
make COLO module optional in further patch (i.e. we are going to add
possibility not build the COLO module).
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Message-Id: <20230428194928.1426370-3-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
It is only used there, so we can make it static.
Once there, remove spice.h that it is not used.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
fix David Edmonson ui/qemu-spice.h unintended removal
There should be no paths from a coroutine_fn to aio_poll, however in
practice coroutine_mixed_fn will call aio_poll in the !qemu_in_coroutine()
path. By marking mixed functions, we can track accurately the call paths
that execute entirely in coroutine context, and find more missing
coroutine_fn markers. This results in more accurate checks that
coroutine code does not end up blocking.
If the marking were extended transitively to all functions that call
these ones, static analysis could be done much more efficiently.
However, this is a start and makes it possible to use vrc's path-based
searches to find potential bugs where coroutine_fns call blocking functions.
Signed-off-by: Paolo Bonzini <pbonzini@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>
We fairly regularly forget VMSTATE_END_OF_LIST markers off descriptions;
given that the current check is only for ->name being NULL, sometimes
we get unlucky and the code apparently works and no one spots the error.
Explicitly add a flag, VMS_END that should be set, and assert it is
set during the traversal.
Note: This can't go in until we update the copy of vmstate.h in slirp.
Suggested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Let's factor out this check, to be used in virtio-mem context next.
While at it, fix a spelling error in a related comment.
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>S
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We'll make use of both next in the context of virtio-mem.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>S
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
For virtio-mem, we want to have the plugged/unplugged state of memory
blocks available before migrating any actual RAM content, and perform
sanity checks before touching anything on the destination. This
information is immutable on the migration source while migration is active,
We want to use this information for proper preallocation support with
migration: currently, we don't preallocate memory on the migration target,
and especially with hugetlb, we can easily run out of hugetlb pages during
RAM migration and will crash (SIGBUS) instead of catching this gracefully
via preallocation.
Migrating device state via a VMSD before we start iterating is currently
impossible: the only approach that would be possible is avoiding a VMSD
and migrating state manually during save_setup(), to be restored during
load_state().
Let's allow for migrating device state via a VMSD early, during the
setup phase in qemu_savevm_state_setup(). To keep it simple, we
indicate applicable VMSD's using an "early_setup" flag.
Note that only very selected devices (i.e., ones seriously messing with
RAM setup) are supposed to make use of such early state migration.
While at it, also use a bool for the "unmigratable" member.
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>S
Signed-off-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Steve Sistare
Cédric Le Goater
Fabiano Rosas
Stefan Hajnoczi
Richard Henderson
Juan Quintela
Marc-André Lureau
Fiona Ebner
Tejus GK
Avihai Horon
Kevin Wolf
David Hildenbrand
Alex Bennée
Vladimir Sementsov-Ogievskiy
Paolo Bonzini
Dr. David Alan Gilbert