Commit Graph

204 Commits

Author SHA1 Message Date
Markus Armbruster
811f865271 Revert "migration: move only_migratable to MigrationState"
This reverts commit 3df663e575.
This reverts commit b605c47b57.

Command line option --only-migratable is for disallowing any
configuration that can block migration.

Initially, --only-migratable set global variable @only_migratable.

Commit 3df663e575 "migration: move only_migratable to MigrationState"
replaced it by MigrationState member @only_migratable.  That was a
mistake.

First, it doesn't make sense on the design level.  MigrationState
captures the state of an individual migration, but --only-migratable
isn't a property of an individual migration, it's a restriction on
QEMU configuration.  With fault tolerance, we could have several
migrations at once.  --only-migratable would certainly protect all of
them.  Storing it in MigrationState feels inappropriate.

Second, it contributes to a dependency cycle that manifests itself as
a bug now.

Putting @only_migratable into MigrationState means its available only
after migration_object_init().

We can't set it before migration_object_init(), so we delay setting it
with a global property (this is fixup commit b605c47b57 "migration:
fix handling for --only-migratable").

We can't get it before migration_object_init(), so anything that uses
it can only run afterwards.

Since migrate_add_blocker() needs to obey --only-migratable, any code
adding migration blockers can run only afterwards.  This contributes
to the following dependency cycle:

* configure_blockdev() must run before machine_set_property()
  so machine properties can refer to block backends

* machine_set_property() before configure_accelerator()
  so machine properties like kvm-irqchip get applied

* configure_accelerator() before migration_object_init()
  so that Xen's accelerator compat properties get applied.

* migration_object_init() before configure_blockdev()
  so configure_blockdev() can add migration blockers

The cycle was closed when recent commit cda4aa9a5a "Create block
backends before setting machine properties" added the first
dependency, and satisfied it by violating the last one.  Broke block
backends that add migration blockers.

Moving @only_migratable into MigrationState was a mistake.  Revert it.

This doesn't quite break the "migration_object_init() before
configure_blockdev() dependency, since migrate_add_blocker() still has
another dependency on migration_object_init().  To be addressed the
next commit.

Note that the reverted commit made -only-migratable sugar for -global
migration.only-migratable=on below the hood.  Documentation has only
ever mentioned -only-migratable.  This commit removes the arcane &
undocumented alternative to -only-migratable again.  Nobody should be
using it.

Conflicts:
	include/migration/misc.h
	migration/migration.c
	migration/migration.h
	vl.c

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190401090827.20793-3-armbru@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
2019-04-02 13:38:05 +02:00
Wei Wang
bd2270608f migration/ram.c: add a notifier chain for precopy
This patch adds a notifier chain for the memory precopy. This enables various
precopy optimizations to be invoked at specific places.

Signed-off-by: Wei Wang <wei.w.wang@intel.com>
CC: Dr. David Alan Gilbert <dgilbert@redhat.com>
CC: Juan Quintela <quintela@redhat.com>
CC: Michael S. Tsirkin <mst@redhat.com>
CC: Peter Xu <peterx@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <1544516693-5395-6-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-03-06 10:49:18 +00:00
Yury Kotov
6cafc8e4dd migration: Add capabilities validation
Currently we don't check which capabilities set in the source QEMU.
We just expect that the target QEMU has the same enabled capabilities.

Add explicit validation for capabilities to make sure that the target VM
has them too. This is enabled for only new capabilities to keep compatibily.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-6-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
  dgilbert: Manual merge
2019-03-06 10:49:17 +00:00
Dr. David Alan Gilbert
7659505c16 migration: Switch to using announce timer
Switch the announcements to using the new announce timer.
Move the code that does it to announce.c rather than savevm
because it really has nothing to do with the actual migration.

Migration starts the announce from bh's and so they're all
in the main thread/bql, and so there's never any racing with
the timers themselves.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2019-03-05 11:27:41 +08:00
Marc-André Lureau
de22ded044 vmstate: constify SaveVMHandlers
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181114133139.27346-1-marcandre.lureau@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23 15:51:47 +00:00
Fei Li
91b02dc750 migration: add more error handling for postcopy_ram_enable_notify
Call postcopy_ram_incoming_cleanup() to do the cleanup when
postcopy_ram_enable_notify fails. Besides, report the error
message when qemu_ram_foreach_migratable_block() fails.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190113140849.38339-5-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2019-01-23 15:02:07 +00:00
Marc-André Lureau
03fee66fde vmstate: constify VMStateField
Because they are supposed to remain const.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181114132931.22624-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-27 15:35:15 +01:00
Paolo Bonzini
5aaac46793 migration: savevm: consult migration blockers
There is really no difference between live migration and savevm, except
that savevm does not require bdrv_invalidate_cache to be implemented
by all disks.  However, it is unlikely that savevm is used with anything
except qcow2 disks, so the penalty is small and worth the improvement
in catching bad usage of savevm.

Only one place was taking care of savevm when adding a migration blocker,
and it can be removed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-27 15:06:14 +01:00
Jia Lina
3d63da16fb migration: avoid segmentfault when take a snapshot of a VM which being migrated
During an active background migration, snapshot will trigger a
segmentfault. As snapshot clears the "current_migration" struct
and updates "to_dst_file" before it finds out that there is a
migration task, Migration accesses the null pointer in
"current_migration" struct and qemu crashes eventually.

Signed-off-by: Jia Lina <jialina01@baidu.com>
Signed-off-by: Chai Wen <chaiwen@baidu.com>
Signed-off-by: Zhang Yu <zhangyu31@baidu.com>
Message-Id: <20181026083620.10172-1-jialina01@baidu.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-10-31 09:38:59 +00:00
Peter Maydell
13399aad4f Error reporting patches for 2018-10-22
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Merge remote-tracking branch 'remotes/armbru/tags/pull-error-2018-10-22' into staging

Error reporting patches for 2018-10-22

# gpg: Signature made Mon 22 Oct 2018 13:20:23 BST
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-error-2018-10-22: (40 commits)
  error: Drop bogus "use error_setg() instead" admonitions
  vpc: Fail open on bad header checksum
  block: Clean up bdrv_img_create()'s error reporting
  vl: Simplify call of parse_name()
  vl: Fix exit status for -drive format=help
  blockdev: Convert drive_new() to Error
  vl: Assert drive_new() does not fail in default_drive()
  fsdev: Clean up error reporting in qemu_fsdev_add()
  spice: Clean up error reporting in add_channel()
  tpm: Clean up error reporting in tpm_init_tpmdev()
  numa: Clean up error reporting in parse_numa()
  vnc: Clean up error reporting in vnc_init_func()
  ui: Convert vnc_display_init(), init_keyboard_layout() to Error
  ui/keymaps: Fix handling of erroneous include files
  vl: Clean up error reporting in device_init_func()
  vl: Clean up error reporting in parse_fw_cfg()
  vl: Clean up error reporting in mon_init_func()
  vl: Clean up error reporting in machine_set_property()
  vl: Clean up error reporting in chardev_init_func()
  qom: Clean up error reporting in user_creatable_add_opts_foreach()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-10-23 17:20:23 +01:00
Markus Armbruster
4dd32b3dda migration: Fix !replay_can_snapshot() error handling
Calling error_report() in a function that takes an Error ** argument
is suspicious.  save_snapshot() and load_snapshot() do that, and then
fail without setting an error.  Wrong.  The HMP commands survive this
unscathed, since hmp_handle_error() does nothing when no error has
been set.  Callers main() (on behalf of -loadvm) and
replay_vmstate_init() crash, but I'm not sure the error is possible
there.

Screwed up when commit 377b21ccea (v2.12.0) added incorrect error
handling right next to correct examples.  Fix by calling error_setg()
instead of error_report().

Fixes: 377b21ccea
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181017082702.5581-13-armbru@redhat.com>
2018-10-19 14:51:34 +02:00
Zhang Chen
3f6df99d9d savevm: split the process of different stages for loadvm/savevm
There are several stages during loadvm/savevm process. In different stage,
migration incoming processes different types of sections.
We want to control these stages more accuracy, it will benefit COLO
performance, we don't have to save type of QEMU_VM_SECTION_START
sections everytime while do checkpoint, besides, we want to separate
the process of saving/loading memory and devices state.

So we add three new helper functions: qemu_load_device_state() and
qemu_savevm_live_state() to achieve different process during migration.

Besides, we make qemu_loadvm_state_main() and qemu_save_device_state()
public, and simplify the codes of qemu_save_device_state() by calling the
wrapper qemu_savevm_state_header().

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen
13af18f222 COLO: Load dirty pages into SVM's RAM cache firstly
We should not load PVM's state directly into SVM, because there maybe some
errors happen when SVM is receving data, which will break SVM.

We need to ensure receving all data before load the state into SVM. We use
an extra memory to cache these data (PVM's ram). The ram cache in secondary side
is initially the same as SVM/PVM's memory. And in the process of checkpoint,
we cache the dirty pages of PVM into this ram cache firstly, so this ram cache
always the same as PVM's memory at every checkpoint, then we flush this cached ram
to SVM after we receive all PVM's state.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Zhang Chen
aad555c229 COLO: Remove colo_state migration struct
We need to know if migration is going into COLO state for
incoming side before start normal migration.

Instead by using the VMStateDescription to send colo_state
from source side to destination side, we use MIG_CMD_ENABLE_COLO
to indicate whether COLO is enabled or not.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2018-10-19 11:15:03 +08:00
Dr. David Alan Gilbert
096c83b721 migration: cleanup in error paths in loadvm
There's a couple of error paths in qemu_loadvm_state
which happen early on but after we've initialised the
load state; that needs to be cleaned up otherwise
we can hit asserts if the state gets reinitialised later.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180914170430.54271-3-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 17:29:01 +01:00
Dr. David Alan Gilbert
9cf4bb8730 migration/postcopy: Clear have_listen_thread
Clear have_listen_thread when we exit the thread.
The fallout from this was that various things thought there was
an ongoing postcopy after the postcopy had finished.

The case that failed was postcopy->savevm->loadvm.

This corresponds to RH bug https://bugzilla.redhat.com/show_bug.cgi?id=1608765

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20180914170430.54271-2-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 17:29:01 +01:00
Jose Ricardo Ziviani
827beacb47 Add a hint message to loadvm and exits on failure
This patch adds a small hint for the failure case of the load snapshot
process. It may be useful for users to remember that the VM
configuration has changed between the save and load processes.

(qemu) loadvm vm-20180903083641
Unknown savevm section or instance 'cpu_common' 4.
Make sure that your current VM setup matches your saved VM setup, including any hotplugged devices
Error -22 while loading VM state
(qemu) device_add host-spapr-cpu-core,core-id=4
(qemu) loadvm vm-20180903083641
(qemu) c
(qemu) info status
VM status: running

It also exits Qemu if the snapshot cannot be loaded before reaching the
main loop (-loadvm in the command line).

$ qemu-system-ppc64 ... -loadvm vm-20180903083641
qemu-system-ppc64: Unknown savevm section or instance 'cpu_common' 4.
Make sure that your current VM setup matches your saved VM setup, including any hotplugged devices
qemu-system-ppc64: Error -22 while loading VM state
$

Signed-off-by: Jose Ricardo Ziviani <joserz@linux.ibm.com>
Message-Id: <20180903162613.15877-1-joserz@linux.ibm.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-09-26 12:26:38 +01:00
Lidong Chen
74637e6f08 migration: implement bi-directional RDMA QIOChannel
This patch implements bi-directional RDMA QIOChannel. Because different
threads may access RDMAQIOChannel currently, this patch use RCU to protect it.

Signed-off-by: Lidong Chen <lidongchen@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-08-22 12:12:26 +02:00
Peter Xu
858b6d6224 migration: reorder MIG_CMD_POSTCOPY_RESUME
It was accidently added before MIG_CMD_PACKAGED so it might break
command compatibility when we run postcopy migration between old/new
QEMUs.  Fix that up quickly before the QEMU 3.0 release.

Reported-by: Lukáš Doktor <ldoktor@redhat.com>
Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180710094424.30754-1-peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 15:23:23 +01:00
Peter Xu
fd037a656a migration: loosen recovery check when load vm
We were checking against -EIO, assuming that it will cover all IO
failures.  But actually it is not.  One example is that in
qemu_loadvm_section_start_full() we can have tons of places that will
return -EINVAL even if the error is caused by IO failures on the
network.

Let's loosen the recovery check logic here to cover all the error cases
happened by removing the explicit check against -EIO.  After all we
won't lose anything here if any other failure happened.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180710091902.28780-3-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 12:56:07 +01:00
Peter Xu
eed1cc7866 migration: delay postcopy paused state
Before this patch we firstly setup the postcopy-paused state then we
clean up the QEMUFile handles.  That can be racy if there is a very fast
"migrate-recover" command running in parallel.  Fix that up.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180627132246.5576-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-07-10 12:48:53 +01:00
Peter Maydell
b74588a493 migration/next for 20180604
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Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20180604' into staging

migration/next for 20180604

# gpg: Signature made Mon 04 Jun 2018 05:14:24 BST
# gpg:                using RSA key F487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/juanquintela/tags/migration/20180604:
  migration: not wait RDMA_CM_EVENT_DISCONNECTED event after rdma_disconnect
  migration: remove unnecessary variables len in QIOChannelRDMA
  migration: Don't activate block devices if using -S
  migration: discard non-migratable RAMBlocks
  migration: introduce decompress-error-check

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-04 12:54:00 +01:00
Cédric Le Goater
b895de5027 migration: discard non-migratable RAMBlocks
On the POWER9 processor, the XIVE interrupt controller can control
interrupt sources using MMIO to trigger events, to EOI or to turn off
the sources. Priority management and interrupt acknowledgment is also
controlled by MMIO in the presenter sub-engine.

These MMIO regions are exposed to guests in QEMU with a set of 'ram
device' memory mappings, similarly to VFIO, and the VMAs are populated
dynamically with the appropriate pages using a fault handler.

But, these regions are an issue for migration. We need to discard the
associated RAMBlocks from the RAM state on the source VM and let the
destination VM rebuild the memory mappings on the new host in the
post_load() operation just before resuming the system.

To achieve this goal, the following introduces a new RAMBlock flag
RAM_MIGRATABLE which is updated in the vmstate_register_ram() and
vmstate_unregister_ram() routines. This flag is then used by the
migration to identify RAMBlocks to discard on the source. Some checks
are also performed on the destination to make sure nothing invalid was
sent.

This change impacts the boston, malta and jazz mips boards for which
migration compatibility is broken.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-06-04 05:46:15 +02:00
Michael S. Tsirkin
83ee768d62 migration: drop an unused include
In the vmstate.h file, we just need a struct name. Use a forward
declaration instead of an include, then adjust the one affected .c file
to include the file that is no longer implicit from the header.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2018-06-01 19:20:37 +03:00
Peter Xu
02affd41b1 qmp/migration: new command migrate-recover
The first allow-oob=true command.  It's used on destination side when
the postcopy migration is paused and ready for a recovery.  After
execution, a new migration channel will be established for postcopy to
continue.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-21-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---
s/2.12/2.13/
2018-05-15 22:11:45 +02:00
Peter Xu
d1b8eadbc4 migration: introduce SaveVMHandlers.resume_prepare
This is hook function to be called when a postcopy migration wants to
resume from a failure. For each module, it should provide its own
recovery logic before we switch to the postcopy-active state.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-16-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:55 +02:00
Peter Xu
13955b89ce migration: new message MIG_RP_MSG_RESUME_ACK
Creating new message to reply for MIG_CMD_POSTCOPY_RESUME. One uint32_t
is used as payload to let the source know whether destination is ready
to continue the migration.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-15-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:53 +02:00
Peter Xu
3f5875eca5 migration: new cmd MIG_CMD_POSTCOPY_RESUME
Introducing this new command to be sent when the source VM is ready to
resume the paused migration.  What the destination does here is
basically release the fault thread to continue service page faults.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-14-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:52 +02:00
Peter Xu
a335debb35 migration: new message MIG_RP_MSG_RECV_BITMAP
Introducing new return path message MIG_RP_MSG_RECV_BITMAP to send
received bitmap of ramblock back to source.

This is the reply message of MIG_CMD_RECV_BITMAP, it contains not only
the header (including the ramblock name), and it was appended with the
whole ramblock received bitmap on the destination side.

When the source receives such a reply message (MIG_RP_MSG_RECV_BITMAP),
it parses it, convert it to the dirty bitmap by inverting the bits.

One thing to mention is that, when we send the recv bitmap, we are doing
these things in extra:

- converting the bitmap to little endian, to support when hosts are
  using different endianess on src/dst.

- do proper alignment for 8 bytes, to support when hosts are using
  different word size (32/64 bits) on src/dst.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-13-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:51 +02:00
Peter Xu
f25d42253c migration: new cmd MIG_CMD_RECV_BITMAP
Add a new vm command MIG_CMD_RECV_BITMAP to request received bitmap for
one ramblock.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-12-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:56:49 +02:00
Peter Xu
3a7804c306 migration: allow fault thread to pause
Allows the fault thread to stop handling page faults temporarily. When
network failure happened (and if we expect a recovery afterwards), we
should not allow the fault thread to continue sending things to source,
instead, it should halt for a while until the connection is rebuilt.

When the dest main thread noticed the failure, it kicks the fault thread
to switch to pause state.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-7-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Xu
b411b844fb migration: allow dst vm pause on postcopy
When there is IO error on the incoming channel (e.g., network down),
instead of bailing out immediately, we allow the dst vm to switch to the
new POSTCOPY_PAUSE state. Currently it is still simple - it waits the
new semaphore, until someone poke it for another attempt.

One note is that here on ram loading thread we cannot detect the
POSTCOPY_ACTIVE state, but we need to detect the more specific
POSTCOPY_INCOMING_RUNNING state, to make sure we have already loaded all
the device states.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180502104740.12123-5-peterx@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2018-05-15 20:24:27 +02:00
Peter Maydell
ed627b2ad3 virtio,vhost,pci,pc: features, cleanups
SRAT tables for DIMM devices
 new virtio net flags for speed/duplex
 post-copy migration support in vhost
 cleanups in pci
 
 Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Merge remote-tracking branch 'remotes/mst/tags/for_upstream' into staging

virtio,vhost,pci,pc: features, cleanups

SRAT tables for DIMM devices
new virtio net flags for speed/duplex
post-copy migration support in vhost
cleanups in pci

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

# gpg: Signature made Tue 20 Mar 2018 14:40:43 GMT
# gpg:                using RSA key 281F0DB8D28D5469
# gpg: Good signature from "Michael S. Tsirkin <mst@kernel.org>"
# gpg:                 aka "Michael S. Tsirkin <mst@redhat.com>"
# Primary key fingerprint: 0270 606B 6F3C DF3D 0B17  0970 C350 3912 AFBE 8E67
#      Subkey fingerprint: 5D09 FD08 71C8 F85B 94CA  8A0D 281F 0DB8 D28D 5469

* remotes/mst/tags/for_upstream: (51 commits)
  postcopy shared docs
  libvhost-user: Claim support for postcopy
  postcopy: Allow shared memory
  vhost: Huge page align and merge
  vhost+postcopy: Wire up POSTCOPY_END notify
  vhost-user: Add VHOST_USER_POSTCOPY_END message
  libvhost-user: mprotect & madvises for postcopy
  vhost+postcopy: Call wakeups
  vhost+postcopy: Add vhost waker
  postcopy: postcopy_notify_shared_wake
  postcopy: helper for waking shared
  vhost+postcopy: Resolve client address
  postcopy-ram: add a stub for postcopy_request_shared_page
  vhost+postcopy: Helper to send requests to source for shared pages
  vhost+postcopy: Stash RAMBlock and offset
  vhost+postcopy: Send address back to qemu
  libvhost-user+postcopy: Register new regions with the ufd
  migration/ram: ramblock_recv_bitmap_test_byte_offset
  postcopy+vhost-user: Split set_mem_table for postcopy
  vhost+postcopy: Transmit 'listen' to slave
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

# Conflicts:
#	scripts/update-linux-headers.sh
2018-03-20 15:48:34 +00:00
Dr. David Alan Gilbert
6864a7b5ac vhost+postcopy: Transmit 'listen' to slave
Notify the vhost-user slave on reception of the 'postcopy-listen'
event from the source.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:28 +02:00
Dr. David Alan Gilbert
d3dff7a5a1 vhost-user: Add 'VHOST_USER_POSTCOPY_ADVISE' message
Wire up a notifier to send a VHOST_USER_POSTCOPY_ADVISE
message on an incoming advise.

Later patches will fill in the behaviour/contents of the
message.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2018-03-20 05:03:27 +02:00
Peter Maydell
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Merge remote-tracking branch 'remotes/jnsnow/tags/bitmaps-pull-request' into staging

# gpg: Signature made Tue 13 Mar 2018 21:11:43 GMT
# gpg:                using RSA key 7DEF8106AAFC390E
# gpg: Good signature from "John Snow (John Huston) <jsnow@redhat.com>"
# Primary key fingerprint: FAEB 9711 A12C F475 812F  18F2 88A9 064D 1835 61EB
#      Subkey fingerprint: F9B7 ABDB BCAC DF95 BE76  CBD0 7DEF 8106 AAFC 390E

* remotes/jnsnow/tags/bitmaps-pull-request:
  iotests: add dirty bitmap postcopy test
  iotests: add dirty bitmap migration test
  migration: add postcopy migration of dirty bitmaps
  migration: allow qmp command migrate-start-postcopy for any postcopy
  migration: add is_active_iterate handler
  migration/qemu-file: add qemu_put_counted_string()
  migration: include migrate_dirty_bitmaps in migrate_postcopy
  qapi: add dirty-bitmaps migration capability
  migration: introduce postcopy-only pending
  dirty-bitmap: add locked state
  block/dirty-bitmap: add _locked version of bdrv_reclaim_dirty_bitmap
  block/dirty-bitmap: fix locking in bdrv_reclaim_dirty_bitmap
  block/dirty-bitmap: add bdrv_dirty_bitmap_enable_successor()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-03-16 14:15:18 +00:00
Vladimir Sementsov-Ogievskiy
b35ebdf076 migration: add postcopy migration of dirty bitmaps
Postcopy migration of dirty bitmaps. Only named dirty bitmaps are migrated.

If destination qemu is already containing a dirty bitmap with the same name
as a migrated bitmap (for the same node), then, if their granularities are
the same the migration will be done, otherwise the error will be generated.

If destination qemu doesn't contain such bitmap it will be created.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-12-vsementsov@virtuozzo.com
[Changed '+' to '*' as per list discussion. --js]
Signed-off-by: John Snow <jsnow@redhat.com>
2018-03-13 17:06:09 -04:00
Vladimir Sementsov-Ogievskiy
c865d84872 migration: add is_active_iterate handler
Only-postcopy savevm states (dirty-bitmap) don't need live iteration, so
to disable them and stop transporting empty sections there is a new
savevm handler.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Message-id: 20180313180320.339796-10-vsementsov@virtuozzo.com
2018-03-13 17:05:58 -04:00
Vladimir Sementsov-Ogievskiy
4799502640 migration: introduce postcopy-only pending
There would be savevm states (dirty-bitmap) which can migrate only in
postcopy stage. The corresponding pending is introduced here.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20180313180320.339796-6-vsementsov@virtuozzo.com
2018-03-13 17:05:41 -04:00
Pavel Dovgalyuk
377b21ccea replay: fix save/load vm for non-empty queue
This patch does not allows saving/loading vmstate when
replay events queue is not empty. There is no reliable
way to save events queue, because it describes internal
coroutine state. Therefore saving and loading operations
should be deferred to another record/replay step.

Signed-off-by: Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>
Message-Id: <20180227095214.1060.32939.stgit@pasha-VirtualBox>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
2018-03-12 16:12:50 +01:00
Markus Armbruster
112ed241f5 qapi: Empty out qapi-schema.json
The previous commit improved compile time by including less of the
generated QAPI headers.  This is impossible for stuff defined directly
in qapi-schema.json, because that ends up in headers that that pull in
everything.

Move everything but include directives from qapi-schema.json to new
sub-module qapi/misc.json, then include just the "misc" shard where
possible.

It's possible everywhere, except:

* monitor.c needs qmp-command.h to get qmp_init_marshal()

* monitor.c, ui/vnc.c and the generated qapi-event-FOO.c need
  qapi-event.h to get enum QAPIEvent

Perhaps we'll get rid of those some other day.

Adding a type to qapi/migration.json now recompiles some 120 instead
of 2300 out of 5100 objects.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180211093607.27351-25-armbru@redhat.com>
[eblake: rebase to master]
Signed-off-by: Eric Blake <eblake@redhat.com>
2018-03-02 13:45:50 -06:00
Peter Xu
3e0c8050eb migration: pass MigrationState to migrate_init()
Let the callers take the object, then pass it to migrate_init().

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-12-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:37:09 +00:00
Peter Xu
7a9ddfbfae migration: better error handling with QEMUFile
If the postcopy down due to some reason, we can always see this on dst:

  qemu-system-x86_64: RP: Received invalid message 0x0000 length 0x0000

However in most cases that's not the real issue. The problem is that
qemu_get_be16() has no way to show whether the returned data is valid or
not, and we are _always_ assuming it is valid. That's possibly not wise.

The best approach to solve this would be: refactoring QEMUFile interface
to allow the APIs to return error if there is. However it needs quite a
bit of work and testing. For now, let's explicitly check the validity
first before using the data in all places for qemu_get_*().

This patch tries to fix most of the cases I can see. Only if we are with
this, can we make sure we are processing the valid data, and also can we
make sure we can capture the channel down events correctly.

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Message-Id: <20180208103132.28452-2-peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:34:56 +00:00
Ross Lagerwall
96994fd1e4 migration/xen: Check return value of qemu_fclose
QEMUFile uses buffered IO so when writing small amounts (such as the Xen
device state file), the actual write call and any errors that may occur
only happen as part of qemu_fclose(). Therefore, report IO errors when
saving the device state under Xen by checking the return value of
qemu_fclose().

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Message-Id: <20180206163039.23661-1-ross.lagerwall@citrix.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-14 10:18:42 +00:00
Markus Armbruster
e688df6bc4 Include qapi/error.h exactly where needed
This cleanup makes the number of objects depending on qapi/error.h
drop from 1910 (out of 4743) to 1612 in my "build everything" tree.

While there, separate #include from file comment with a blank line,
and drop a useless comment on why qemu/osdep.h is included first.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180201111846.21846-5-armbru@redhat.com>
[Semantic conflict with commit 34e304e975 resolved, OSX breakage fixed]
2018-02-09 13:50:17 +01:00
Greg Kurz
875fcd013a migration: incoming postcopy advise sanity checks
If postcopy-ram was set on the source but not on the destination,
migration doesn't occur, the destination prints an error and boots
the guest:

qemu-system-ppc64: Expected vmdescription section, but got 0

We end up with two running instances.

This behaviour was introduced in 2.11 by commit 58110f0acb "migration:
split common postcopy out of ram postcopy" to prepare ground for the
upcoming dirty bitmap postcopy support. It adds a new case where the
source may send an empty postcopy advise because dirty bitmap doesn't
need to check page sizes like RAM postcopy does.

If the source has enabled postcopy-ram, then it sends an advise with
the page size values. If the destination hasn't enabled postcopy-ram,
then loadvm_postcopy_handle_advise() leaves the page size values on
the stream and returns. This confuses qemu_loadvm_state() later on
and causes the destination to start execution.

As discussed several times, postcopy-ram should be enabled both sides
to be functional. This patch changes the destination to perform some
extra checks on the advise length to ensure this is the case. Otherwise
an error is returned and migration is aborted.

Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <151791621042.19120.3103118434734245776.stgit@bahia>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 14:53:02 +00:00
Ross Lagerwall
032b79f717 migration: Don't leak IO channels
Since qemu_fopen_channel_{in,out}put take references on the underlying
IO channels, make sure to release our references to them.

Signed-off-by: Ross Lagerwall <ross.lagerwall@citrix.com>
Message-Id: <20171101142526.1006-2-ross.lagerwall@citrix.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 14:53:02 +00:00
Daniel Henrique Barboza
ee555cdf4d migration/savevm.c: set MAX_VM_CMD_PACKAGED_SIZE to 1ul << 32
MAX_VM_CMD_PACKAGED_SIZE is a constant used in qemu_savevm_send_packaged
and loadvm_handle_cmd_packaged to determine whether a package is too
big to be sent or received. qemu_savevm_send_packaged is called inside
postcopy_start (migration/migration.c) to send the MigrationState
in a single blob to the destination, using the MIG_CMD_PACKAGED subcommand,
which will read it up using loadvm_handle_cmd_packaged. If the blob is
larger than MAX_VM_CMD_PACKAGED_SIZE, an error is thrown and the postcopy
migration is aborted. Both MAX_VM_CMD_PACKAGED_SIZE and MIG_CMD_PACKAGED
were introduced by commit 11cf1d984b ("MIG_CMD_PACKAGED: Send a packaged
chunk ..."). The constant has its original value of 1ul << 24 (16MB).

The current MAX_VM_CMD_PACKAGED_SIZE value is not enough to support postcopy
migration of bigger pseries guests. The blob size for a postcopy migration of
a pseries guest with the following setup:

qemu-system-ppc64 --nographic -vga none -machine pseries,accel=kvm -m 64G \
-smp 1,maxcpus=32 -device virtio-blk-pci,drive=rootdisk \
-drive file=f27.qcow2,if=none,cache=none,format=qcow2,id=rootdisk \
-netdev user,id=u1 -net nic,netdev=u1

Goes around 12MB. Bumping the RAM to 128G makes the blob sizes goes to 20MB.
With 256G the blob goes to 37MB - more than twice the current maximum size.
At this moment the pseries machine can handle guests with up to 1TB of RAM,
making this postcopy blob goes to 128MB of size approximately.

Following the discussions made in [1], there is a need to understand what
devices are aggressively consuming the blob in that manner and see if that
can be mitigated. Until then, we can set MAX_VM_CMD_PACKAGED_SIZE to the
maximum value allowed. Since the size is a 32 bit int variable, we can set
it as 1ul << 32, giving a maximum blob size of 4G that is enough to support
postcopy migration of 32TB RAM guests given the above constraints.

[1] https://lists.nongnu.org/archive/html/qemu-devel/2018-01/msg06313.html

Signed-off-by: Daniel Henrique Barboza <danielhb@linux.vnet.ibm.com>
Reported-by: Balamuruhan S <bala24@linux.vnet.ibm.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
2018-02-06 10:55:13 +00:00
Anthony PERARD
5d6c599fe1 migration, xen: Fix block image lock issue on live migration
When doing a live migration of a Xen guest with libxl, the images for
block devices are locked by the original QEMU process, and this prevent
the QEMU at the destination to take the lock and the migration fail.

>From QEMU point of view, once the RAM of a domain is migrated, there is
two QMP commands, "stop" then "xen-save-devices-state", at which point a
new QEMU is spawned at the destination.

Release locks in "xen-save-devices-state" so the destination can takes
them, if it's a live migration.

This patch add the "live" parameter to "xen-save-devices-state" which
default to true so older version of libxenlight can work with newer
version of QEMU.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
2017-11-21 19:42:26 +01:00
Kevin Wolf
2b624fe079 block: Add errp to bdrv_all_goto_snapshot()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>
2017-11-21 14:48:22 +01:00