Add the last_colo_mode to save the status after failover.
This patch can solve the issue that user want to get last colo mode
use query_colo_status after failover.
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.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>
In this patch we add the processing state for COLOExitReason,
because we have to identify COLO in the failover processing state or
failover error state. In the way, we can handle all the failover state.
We have improved the description of the COLOExitReason by the way.
Signed-off-by: Zhang Chen <chen.zhang@intel.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>
When finished COLO failover, the status is FAILOVER_STATUS_COMPLETED.
The origin codes misunderstand the FAILOVER_STATUS_REQUIRE.
Signed-off-by: Zhang Chen <chen.zhang@intel.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>
Actually it can't fail at the moment, but Coverity moans that
it's the only place it's not checked, and it's an easy check.
Reported-by: Coverity (CID 1399413)
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>
The QEMU instance that runs as the server for the migration data
transport (ie the target QEMU) needs to be able to configure access
control so it can prevent unauthorized clients initiating an incoming
migration. This adds a new 'tls-authz' migration parameter that is used
to provide the QOM ID of a QAuthZ subclass instance that provides the
access control check. This is checked against the x509 certificate
obtained during the TLS handshake.
For example, when starting a QEMU for incoming migration, it is
possible to give an example identity of the source QEMU that is
intended to be connecting later:
$QEMU \
-monitor stdio \
-incoming defer \
...other args...
(qemu) object_add tls-creds-x509,id=tls0,dir=/home/berrange/qemutls,\
endpoint=server,verify-peer=yes \
(qemu) object_add authz-simple,id=auth0,identity=CN=laptop.example.com,,\
O=Example Org,,L=London,,ST=London,,C=GB \
(qemu) migrate_incoming tcp:localhost:9000
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We make it supported from now on.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Add some padding.
MultifdInit_t is padded to 64 bytes.
MultiFDPacket_t is padded to 320bytes (64 * 5).
Signed-off-by: Juan Quintela <quintela@redhat.com>
We moved from 64KB to 512KB, as it makes less locking contention
without any downside in testing.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This way we can change the packet size in the future and everything
will work. We choose an arbitrary big number (100 times configured
size) as a limit about how big we will reallocate.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Libvirt don't want to expose (and explain it). From now on we measure
the number of packages in bytes instead of pages, so it is the same
independently of architecture. We choose the page size of x86.
Notice that in the following patch we make this variable.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We need to send this field when we add compression support. As we are
still on x- stage, we can do this kind of changes.
Signed-off-by: Juan Quintela <quintela@redhat.com>
It really indicates what is the number of allocated pages for one
packet. Once there rename "used" to "pages_used".
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We send packages without pages sometimes for sysnchronizanion. The
iov functions do the right thing, but we will be changing this code in
future patches.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Commit a88b179f introduced the ability to set and query bitmap
persistence, but with an atypical spelling.
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20190308205845.25734-1-eblake@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
Instead of checking against busy, inconsistent, or read only directly,
use a check function with permissions bits that let us streamline the
checks without reproducing them in many places.
Included in this patch are permissions changes that simply add the
inconsistent check to existing permissions call spots, without
addressing existing bugs.
In general, this means that busy+readonly checks become BDRV_BITMAP_DEFAULT,
which checks against all three conditions. busy-only checks become
BDRV_BITMAP_ALLOW_RO.
Notably, remove allows inconsistent bitmaps, so it doesn't follow the pattern.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190301191545.8728-4-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
These mean the same thing now. Unify them and rename the merged call
bdrv_dirty_bitmap_busy to indicate semantically what we are describing,
as well as help disambiguate from the various _locked and _unlocked
versions of bitmap helpers that refer to mutex locks.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190223000614.13894-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
"Frozen" was a good description a long time ago, but it isn't adequate now.
Rename the frozen predicate to has_successor to make the semantics of the
predicate more clear to outside callers.
In the process, remove some calls to frozen() that no longer semantically
make sense. For bdrv_enable_dirty_bitmap_locked and
bdrv_disable_dirty_bitmap_locked, it doesn't make sense to prohibit QEMU
internals from performing this action when we only wished to prohibit QMP
users from issuing these commands. All of the QMP API commands for bitmap
manipulation already check against user_locked() to prohibit these actions.
Several other assertions really want to check that the bitmap isn't in-use
by another operation -- use the bitmap_user_locked function for this instead,
which presently also checks for has_successor. This leaves some redundant
checks of has_successor through different helpers that are addressed in
forthcoming patches.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190223000614.13894-3-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
slirp migration code uses QEMU vmstate so far, when building WITH_QEMU.
Introduce slirp_state_{load,save,version}() functions to move the
state saving handling to libslirp side.
So far, the bitstream compatibility should remain equal with current
QEMU, as this is effectively using the same code, with the same format
etc. When libslirp is made standalone, we will need some mechanism to
ensure bitstream compatibility regardless of the libslirp version
installed. See the FIXME note in the code.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20190212162524.31504-3-marcandre.lureau@redhat.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Delay to close COLO for auto start VM after failover.
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190303145021.2962-4-chen.zhang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
In migration_incoming_state_destroy(void) will check the mis->to_src_file
to double close the mis->to_src_file when occur COLO failover.
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190303145021.2962-2-chen.zhang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This patch adds the free page optimization enable flag, and a function
to set this flag. When the free page optimization is enabled, not all
the pages are needed to be sent in the bulk stage.
Why using a new flag, instead of directly disabling ram_bulk_stage when
the optimization is running?
Thanks for Peter Xu's reminder that disabling ram_bulk_stage will affect
the use of compression. Please see save_page_use_compression. When
xbzrle and compression are used, if free page optimizaion causes the
ram_bulk_stage to be disabled, save_page_use_compression will return
false, which disables the use of compression. That is, if free page
optimization avoids the sending of half of the guest pages, the other
half of pages loses the benefits of compression in the meantime. Using a
new flag to let migration_bitmap_find_dirty skip the free pages in the
bulk stage will avoid the above issue.
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>
Message-Id: <1544516693-5395-7-git-send-email-wei.w.wang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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>
This patch adds an API to clear bits corresponding to guest free pages
from the dirty bitmap. Spilt the free page block if it crosses the QEMU
RAMBlock boundary.
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: <1544516693-5395-5-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
The bitmap mutex is used to synchronize threads to update the dirty
bitmap and the migration_dirty_pages counter. For example, the free
page optimization clears bits of free pages from the bitmap in an
iothread context. This patch makes migration_bitmap_clear_dirty update
the bitmap and counter under the mutex.
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: <1544516693-5395-4-git-send-email-wei.w.wang@intel.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
It will be used to store the uri parameters. We want this only for
tcp, so we don't set it for other uris. We need it to know what port
is migration running.
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
dgilbert: Removed DummyStruct as suggested by Eric & Markus
--
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
If ignore-shared capability is set then skip shared RAMBlocks during the
RAM migration.
Also, move qemu_ram_foreach_migratable_block (and rename) to the
migration code, because it requires access to the migration capabilities.
Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-4-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
We want to use local migration to update QEMU for running guests.
In this case we don't need to migrate shared (file backed) RAM.
So, add a capability to ignore such blocks during live migration.
Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-3-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Currently, qemu_ram_foreach_* calls RAMBlockIterFunc with many
block-specific arguments. But often iter func needs RAMBlock*.
This refactoring is needed for fast access to RAMBlock flags from
qemu_ram_foreach_block's callback. The only way to achieve this now
is to call qemu_ram_block_from_host (which also enumerates blocks).
So, this patch reduces complexity of
qemu_ram_foreach_block() -> cb() -> qemu_ram_block_from_host()
from O(n^2) to O(n).
Fix RAMBlockIterFunc definition and add some functions to read
RAMBlock* fields witch were passed.
Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-2-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Configuring QEMU with:
../configure --cc=clang --enable-rdma
Leads to compilation error:
CC migration/rdma.o
CC migration/block.o
qemu/migration/rdma.c:3615:58: error: taking address of packed member 'rkey' of class or structure
'RDMARegisterResult' may result in an unaligned pointer value [-Werror,-Waddress-of-packed-member]
(uintptr_t)host_addr, NULL, ®_result->rkey,
^~~~~~~~~~~~~~~~
Fix it by using a temp local variable.
Signed-off-by: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Message-Id: <20190304184923.24215-1-marcel.apfelbaum@gmail.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Currently we cleanup the migration object as we exit main after the
main_loop finishes; however if there's a migration running things
get messy and we can end up with the migration thread still trying
to access freed structures.
We now take a ref to the object around the migration thread itself,
so the act of dropping the ref during exit doesn't cause us to lose
the state until the thread quits.
Cancelling the migration during migration also tries to get the thread
to quit.
We do this a bit earlier; so hopefully migration gets out of the way
before all the devices etc are freed.
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190227164900.16378-1-dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
If the migration fails before the channel is open (e.g. a bad
address) we end up in the cleanup with rdma->channel==NULL.
Spotted by Coverity: CID 1398634
Fixes: fbbaacab27
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190214185351.5927-1-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
During a cancelled migration there's a race where the fd can
go into an error state before we get back around the migration loop
and migration_detect_error transitions from cancelling->failed.
Check for cancelled/cancelling and don't change the state.
Red Hat bug: https://bugzilla.redhat.com/show_bug.cgi?id=1608649
Fixes: b23c2ade25
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190219195928.12289-1-dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
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>
Add migration parameters that control RARP/GARP announcement timeouts.
Based on earlier patches by myself and
Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
The 'announce timer' will be used by migration, and explicit
requests for qemu to perform network announces.
Based on the work by Germano Veit Michel <germano@redhat.com>
and Vlad Yasevich <vyasevic@redhat.com>
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>
Use new qemu_iovec_init_buf() instead of
qemu_iovec_init_external( ... , 1), which simplifies the code.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20190218140926.333779-14-vsementsov@virtuozzo.com
Message-Id: <20190218140926.333779-14-vsementsov@virtuozzo.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
It introduces a new statistic, pages-per-second, as bandwidth or mbps is
not enough to measure the performance of posting pages out as we have
compression, xbzrle, which can significantly reduce the amount of the
data size, instead, pages-per-second is the one we want
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20190111063732.10484-2-xiaoguangrong@tencent.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
With typo's Eric spotted fixed
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>
Unregister the fd handler before we destroy the channel,
otherwise we've got a race where we might land in the
fd handler just as we're closing the device.
(The race is quite data dependent, you just have to have
the right set of devices for it to trigger).
Corresponds to RH bz: https://bugzilla.redhat.com/show_bug.cgi?id=1666601
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190122173111.29821-1-dgilbert@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
In the current code, if process_incoming_migration_co() fails we do
the same error handing: set the error state, close the source file,
do the cleanup for multifd, and then exit(EXIT_FAILURE). To make the
code clearer, add a "goto fail" to unify the error handling.
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: <20190113140849.38339-6-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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>
multifd_save_cleanup() takes an Error ** argument and returns an
error code even though it can't actually fail. Its callers
dutifully check for failure. Remove the useless argument and return
value, and simplify the callers.
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20190113140849.38339-4-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
In our current code, when multifd is used during migration, if there
is an error before the destination receives all new channels, the
source keeps running, however the destination does not exit but keeps
waiting until the source is killed deliberately.
Fix this by dumping the specific error and let users decide whether
to quit from the destination side when failing to receive packet via
some channel. And update the comment for multifd_recv_new_channel().
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20190113140849.38339-3-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
In some cases it may be helpful to modify state before saving it for
migration, and then modify the state back after it has been saved. The
existing pre_save function provides half of this functionality. This
patch adds a post_save function to provide the second half.
Signed-off-by: Aaron Lindsay <aclindsa@gmail.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-id: 20181211151945.29137-2-aaron@os.amperecomputing.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
GCC 8 introduced the -Wstringop-overflow, which detect buffer overflow
by string-modifying functions declared in <string.h>, such strncpy(),
used in global_state_store_running().
GCC indeed found an incorrect use of strlen(), because this array
is loaded by VMSTATE_BUFFER(runstate, GlobalState) then parsed
using qapi_enum_parse which does not get the buffer length.
Use strnlen() which returns sizeof(s->runstate) if the array is not
NUL-terminated, assert the size is within range, and enforce the array
to be NUL-terminated to avoid an overflow in qapi_enum_parse().
This fixes:
CC migration/global_state.o
qemu/migration/global_state.c: In function 'global_state_pre_save':
qemu/migration/global_state.c:109:15: error: 'strlen' argument 1 declared attribute 'nonstring' [-Werror=stringop-overflow=]
s->size = strlen((char *)s->runstate) + 1;
^~~~~~~~~~~~~~~~~~~~~~~~~~~
qemu/migration/global_state.c:24:13: note: argument 'runstate' declared here
uint8_t runstate[100] QEMU_NONSTRING;
^~~~~~~~
cc1: all warnings being treated as errors
make: *** [qemu/rules.mak:69: migration/global_state.o] Error 1
Suggested-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
GCC 8 added a -Wstringop-truncation warning:
The -Wstringop-truncation warning added in GCC 8.0 via r254630 for
bug 81117 is specifically intended to highlight likely unintended
uses of the strncpy function that truncate the terminating NUL
character from the source string.
This new warning leads to compilation failures:
CC migration/global_state.o
qemu/migration/global_state.c: In function 'global_state_store_running':
qemu/migration/global_state.c:45:5: error: 'strncpy' specified bound 100 equals destination size [-Werror=stringop-truncation]
strncpy((char *)global_state.runstate, state, sizeof(global_state.runstate));
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
make: *** [qemu/rules.mak:69: migration/global_state.o] Error 1
Adding an assert is enough to silence GCC.
(alternatively, we could hard-code "running")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
[PMD: More verbose commit message]
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
