Migrating a VM during reboot sometimes results in differences
between the source and destination in the SMRAM area.
This is because migration_bitmap_sync() only fetches from KVM
the dirty log of address_space_memory. SMRAM memory slots
are ignored and the modifications to SMRAM are not sent to the
destination.
Reported-by: He Rongguang <herongguang.he@huawei.com>
Reviewed-by: He Rongguang <herongguang.he@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Since the two users don't make use of the returned offset,
beyond ensuring that the entire buffer is zero, consider the
can_use_buffer_find_nonzero_offset and buffer_find_nonzero_offset
functions internal.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Message-Id: <1472496380-19706-4-git-send-email-rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use qemu_put_compression_data to do the compression directly
instead of using do_compress_ram_page, avoid some data copy.
very small improvement, at the same time, add code to check
if the compression is successful.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-6-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Current qemu_put_compression_data can only work with no writable
QEMUFile, and can't work with the writable QEMUFile. But it does
not provide any measure to prevent users from using it with a
writable QEMUFile.
We should fix this flaw to make it works with writable QEMUFile.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Suggested-by: Juan Quintela <quintela@redhat.com>
Message-Id: <1462433579-13691-5-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
At the end of live migration and before vm_start() on the destination
side, we should make sure all the decompression tasks are finished, if
this can not be guaranteed, the VM may get the incorrect memory data,
or the updated memory may be overwritten by the decompression thread.
Add the code to fix this potential issue.
Suggested-by: David Alan Gilbert <dgilbert@redhat.com>
Suggested-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-3-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
Recently, a bug related to multiple thread compression feature for
live migration is reported. The destination side will be blocked
during live migration if there are heavy workload in host and
memory intensive workload in guest, this is most likely to happen
when there is one decompression thread.
Some parts of the decompression code are incorrect:
1. The main thread receives data from source side will enter a busy
loop to wait for a free decompression thread.
2. A lock is needed to protect the decomp_param[idx]->start, because
it is checked in the main thread and is updated in the decompression
thread.
Fix these two issues by following the code pattern for compression.
Signed-off-by: Liang Li <liang.z.li@intel.com>
Reported-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Tested-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Liang Li <liang.z.li@intel.com>
Message-Id: <1462433579-13691-2-git-send-email-liang.z.li@intel.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
The MigrateState struct uses an array for storing migration
parameters. This presumes that all future parameters will
be integers too, which is not going to be the case. There
is no functional reason why an array is used, if anything
it makes the code less clear. The QAPI schema already
defines a struct - MigrationParameters - capable of storing
all the individual parameters, so just use that instead of
an array.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1461751518-12128-25-git-send-email-berrange@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
migration fixes:
- ensure src block devices continue fine after a failed migration
- fail on migration blockers; helps 9p savevm/loadvm
- move autoconverge commands out of experimental state
- move the migration-specific qjson in migration/
# gpg: Signature made Mon 23 May 2016 18:15:09 BST using RSA key ID 657EF670
# gpg: Good signature from "Amit Shah <amit@amitshah.net>"
# gpg: aka "Amit Shah <amit@kernel.org>"
# gpg: aka "Amit Shah <amitshah@gmx.net>"
* remotes/amit-migration/tags/migration-2.7-1:
migration: regain control of images when migration fails to complete
savevm: fail if migration blockers are present
migration: Promote improved autoconverge commands out of experimental state
migration/qjson: Drop gratuitous use of QOM
migration: Move qjson.[ch] to migration/
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)
Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Although accesses to ram_list.dirty_memory[] use atomics so multiple
threads can safely dirty the bitmap, the data structure is not fully
thread-safe yet.
This patch handles the RAM hotplug case where ram_list.dirty_memory[] is
grown. ram_list.dirty_memory[] is change from a regular bitmap to an
RCU array of pointers to fixed-size bitmap blocks. Threads can continue
accessing bitmap blocks while the array is being extended. See the
comments in the code for an in-depth explanation of struct
DirtyMemoryBlocks.
I have tested that live migration with virtio-blk dataplane works.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <1453728801-5398-2-git-send-email-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Replace the uint8 softfloat-specific typedef with uint8_t.
This change was made with
find include hw fpu target-* -name '*.[ch]' | xargs sed -i -e 's/\buint8\b/uint8_t/g'
together with manual removal of the typedef definition and
manual fixing of more erroneous uses found via test compilation.
It turns out that the only code using this type is an accidental
use where uint8_t was intended anyway...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Acked-by: Leon Alrae <leon.alrae@imgtec.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Message-id: 1452603315-27030-7-git-send-email-peter.maydell@linaro.org
Error reporting patches for 2016-01-13
# gpg: Signature made Wed 13 Jan 2016 14:21:48 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>"
* remotes/armbru/tags/pull-error-2016-01-13: (41 commits)
checkpatch: Detect newlines in error_report and other error functions
error: Consistently name Error * objects err, and not errp
s390/sclp: Simplify control flow in sclp_realize()
hw/s390x: Rename local variables Error *l_err to just err
error: Clean up errors with embedded newlines (again)
vhdx: Fix "log that needs to be replayed" error message
pci-assign: Clean up "Failed to assign" error messages
vmdk: Clean up "Invalid extent lines" error message
vmdk: Clean up control flow in vmdk_parse_extents() a bit
error: Strip trailing '\n' from error string arguments (again)
qemu-io qemu-nbd: Use error_report() etc. instead of fprintf()
migration: Use error_reportf_err() instead of monitor_printf()
spapr: Use error_reportf_err()
error: Use error_prepend() where it makes obvious sense
error: Use error_reportf_err() where it makes obvious sense
error: Don't decorate original error message when adding to it
error: New error_prepend(), error_reportf_err()
test-throttle: Simplify qemu_init_main_loop() error handling
qemu-nbd: Clean up "Failed to load snapshot" error message
block: Clean up "Could not create temporary overlay" error message
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
My fix (84e7b80a) replaced the last_sent_block update that I'd
removed earlier; however it was too aggressive in the xbzrle case.
save_xbzrle_page might return '0' to mean that the page didn't
need sending since it was the same as the last sent version;
in this case we can't update 'last_sent_block' since we didn't
actually send it.
Symptom: 'Illegal RAM offset 1018000' as we try and send a page
to the wrong RAMBlock; potentially that could be a data
corruption if you were really unlucky.
Fixes: 84e7b80a05
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-id: 1449765106-6528-1-git-send-email-dgilbert@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
In a82d593b61 I accidentally removed the setting of
last_sent_block, put it back.
Symptoms:
Multithreaded compression only uses one thread.
Migration is a bit less efficient since it won't use 'cont' flags.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Fixes: a82d593b61
Signed-off-by: Juan Quintela <quintela@redhat.com>
Where the target page size is different from the host page
we special case it, but I messed up on the zero case check.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Prior to the start of postcopy, ensure that everything that will
be transferred later is a whole host-page in size.
This is accomplished by discarding partially transferred host pages
and marking any that are partially dirty as fully dirty.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Once we're in postcopy the source processors are stopped and memory
shouldn't change any more, so there's no need to look at the dirty
map.
There are two notes to this:
1) If we do resync and a page had changed then the page would get
sent again, which the destination wouldn't allow (since it might
have also modified the page)
2) Before disabling this I'd seen very rare cases where a page had been
marked dirtied although the memory contents are apparently identical
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Ensure that target pages received within a host page are in order.
This shouldn't trigger, but in the cases where the sender goes
wrong and sends stuff out of order it produces a corruption that's
really nasty to debug.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
In postcopy, the destination guest is running at the same time
as it's receiving pages; as we receive new pages we must put
them into the guests address space atomically to avoid a running
CPU accessing a partially written page.
Use the helpers in postcopy-ram.c to map these pages.
qemu_get_buffer_in_place is used to avoid a copy out of qemu_file
in the case that postcopy is going to do a copy anyway.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
When transmitting RAM pages, consume pages that have been queued by
MIG_RPCOMM_REQPAGE commands and send them ahead of normal page scanning.
Note:
a) After a queued page the linear walk carries on from after the
unqueued page; there is a reasonable chance that the destination
was about to ask for other closeby pages anyway.
b) We have to be careful of any assumptions that the page walking
code makes, in particular it does some short cuts on its first linear
walk that break as soon as we do a queued page.
c) We have to be careful to not break up host-page size chunks, since
this makes it harder to place the pages on the destination.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Soon we'll be in either ACTIVE or POSTCOPY_ACTIVE when we
complete migration, and we need to know which we expect to be
in to change state safely.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Maintain an 'unsentmap' of pages that have yet to be sent.
This is used in the following patches to discard some set of
the pages already sent as we enter postcopy mode.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Add qemu_savevm_state_complete_postcopy to complement
qemu_savevm_state_complete_precopy together with a new
save_live_complete_postcopy method on devices.
The save_live_complete_precopy method is called on
all devices during a precopy migration, and all non-postcopy
devices during a postcopy migration at the transition.
The save_live_complete_postcopy method is called at
the end of postcopy for all postcopiable devices.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
In postcopy we're going to need to perform the complete phase
for postcopiable devices at a different point, start out by
renaming all of the 'complete's to make the difference obvious.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The main RAM load loop has a call to host_from_stream_offset for
each page type that actually loads data with the same test;
factor it out before the switch.
The host = NULL is to silence a bogus gcc warning of
an unitialised in the RAM_SAVE_COMPRESS_PAGE case, it
doesn't seem to realise that host is always initialised by the if at
the top in the cases the switch takes.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Useful for debugging the migration bitmap and other bitmaps
of the same format (including the sentmap in postcopy).
The bitmap is printed to stderr.
Lines that are all the expected value are excluded so the output
can be quite compact for many bitmaps.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
