We generally require same set of capabilities on source and target.
Let's require x-colo capability to use COLO on target.
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: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Zhang Chen <chen.zhang@intel.com>
Message-Id: <20230428194928.1426370-11-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
COLO is not listed as running state in migrate_is_running(), so, it's
theoretically possible to disable colo capability in COLO state and the
unexpected error in migration_iteration_finish() is reachable.
Let's disallow that in qmp_migrate_set_capabilities. Than the error
becomes absolutely unreachable: we can get into COLO state only with
enabled capability and can't disable it while we are in COLO state. So
substitute the error by simple assertion.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Message-Id: <20230428194928.1426370-10-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
have_colo_incoming_thread variable is unused. colo_incoming_thread can
be local.
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: <20230428194928.1426370-6-vsementsov@yandex-team.ru>
Signed-off-by: Juan Quintela <quintela@redhat.com>
We don't allow to use x-colo capability when replication is not
configured. So, no reason to build COLO when replication is disabled,
it's unusable in this case.
Note also that the check in migrate_caps_check() is not the only
restriction: some functions in migration/colo.c will just abort if
called with not defined CONFIG_REPLICATION, for example:
migration_iteration_finish()
case MIGRATION_STATUS_COLO:
migrate_start_colo_process()
colo_process_checkpoint()
abort()
It could probably make sense to have possibility to enable COLO without
REPLICATION, but this requires deeper audit of colo & replication code,
which may be done later if needed.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: Dr. David Alan Gilbert <dave@treblig.org>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20230428194928.1426370-4-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>
This will be used in the next commits to add colo support to multifd.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <88135197411df1a71d7832962b39abf60faf0021.1683572883.git.lukasstraub2@web.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This is not required, colo_flush_ram_cache does not run concurrently
with the multifd threads since the cache is only flushed after
everything has been received. But it makes me more comfortable.
This will be used in the next commits to add colo support to multifd.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <35cb23ba854151d38a31e3a5c8a1020e4283cb4a.1683572883.git.lukasstraub2@web.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>
The overhead of the mutex in non-multifd mode is negligible,
because in that case its just the single thread taking the mutex.
This will be used in the next commits to add colo support to multifd.
Signed-off-by: Lukas Straub <lukasstraub2@web.de>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <22d83cb428f37929563155531bfb69fd8953cc61.1683572883.git.lukasstraub2@web.de>
Signed-off-by: Juan Quintela <quintela@redhat.com>
- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add configure options for vmdk, vhdx and vpc
- Fix use after free in blockdev_mark_auto_del()
- migration: Attempt disk reactivation in more failure scenarios
- Coroutine correctness fixes
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Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging
Block layer patches
- Graph locking, part 3 (more block drivers)
- Compile out assert_bdrv_graph_readable() by default
- Add configure options for vmdk, vhdx and vpc
- Fix use after free in blockdev_mark_auto_del()
- migration: Attempt disk reactivation in more failure scenarios
- Coroutine correctness fixes
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# gpg: Signature made Wed 10 May 2023 01:18:41 PM BST
# gpg: using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg: issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (28 commits)
block: compile out assert_bdrv_graph_readable() by default
block: Mark bdrv_refresh_limits() and callers GRAPH_RDLOCK
block: Mark bdrv_recurse_can_replace() and callers GRAPH_RDLOCK
block: Mark bdrv_query_block_graph_info() and callers GRAPH_RDLOCK
block: Mark bdrv_query_bds_stats() and callers GRAPH_RDLOCK
block: Mark BlockDriver callbacks for amend job GRAPH_RDLOCK
block: Mark bdrv_co_debug_event() GRAPH_RDLOCK
block: Mark bdrv_co_get_info() and callers GRAPH_RDLOCK
block: Mark bdrv_co_get_allocated_file_size() and callers GRAPH_RDLOCK
mirror: Require GRAPH_RDLOCK for accessing a node's parent list
vhdx: Require GRAPH_RDLOCK for accessing a node's parent list
nbd: Mark nbd_co_do_establish_connection() and callers GRAPH_RDLOCK
nbd: Remove nbd_co_flush() wrapper function
block: .bdrv_open is non-coroutine and unlocked
graph-lock: Fix GRAPH_RDLOCK_GUARD*() to be reader lock
graph-lock: Add GRAPH_UNLOCKED(_PTR)
test-bdrv-drain: Don't modify the graph in coroutines
iotests: Test resizing image attached to an iothread
block: Don't call no_coroutine_fns in qmp_block_resize()
block: bdrv/blk_co_unref() for calls in coroutine context
...
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
reader_count() is a performance bottleneck because the global
aio_context_list_lock mutex causes thread contention. Put this debugging
assertion behind a new ./configure --enable-debug-graph-lock option and
disable it by default.
The --enable-debug-graph-lock option is also enabled by the more general
--enable-debug option.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230501173443.153062-1-stefanha@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_refresh_limits() need to hold a reader lock for the graph because
it accesses the children list of a node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-21-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_recurse_can_replace() need to hold a reader lock for the graph
because it accesses the children list of a node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-20-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_query_block_graph_info() need to hold a reader lock for the graph
because it accesses the children list of a node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-19-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_query_bds_stats() need to hold a reader lock for the graph because
it accesses the children list of a node.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-18-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of amend
callbacks in BlockDriver need to hold a reader lock for the graph.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-17-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_debug_event() need to hold a reader lock for the graph.
Unfortunately we cannot use a co_wrapper_bdrv_rdlock (i.e. make the
coroutine wrapper a no_coroutine_fn), because the function is called
(using the BLKDBG_EVENT macro) by mixed functions that run both in
coroutine and non-coroutine context (for example many of the functions
in qcow2-cluster.c and qcow2-refcount.c).
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-16-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_get_info() need to hold a reader lock for the graph.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-15-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_get_allocated_file_size() need to hold a reader lock for the
graph.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230504115750.54437-14-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that functions accessing
the parent list of a node need to hold a reader lock for the graph. As
it happens, they already do.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230504115750.54437-13-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that functions accessing
the parent list of a node need to hold a reader lock for the graph. As
it happens, they already do.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-12-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This adds GRAPH_RDLOCK annotations to declare that callers of
nbd_co_do_establish_connection() need to hold a reader lock for the
graph.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-11-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The only thing nbd_co_flush() does is call nbd_client_co_flush(). Just
use that function directly in the BlockDriver definitions and remove the
wrapper.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-10-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Drivers were a bit confused about whether .bdrv_open can run in a
coroutine and whether or not it holds a graph lock.
It cannot keep a graph lock from the caller across the whole function
because it both changes the graph (requires a writer lock) and does I/O
(requires a reader lock). Therefore, it should take these locks
internally as needed.
The functions used to be called in coroutine context during image
creation. This was buggy for other reasons, and as of commit 32192301,
all block drivers go through no_co_wrappers. So it is not called in
coroutine context any more.
Fix qcow2 and qed to work with the correct assumptions: The graph lock
needs to be taken internally instead of just assuming it's already
there, and the coroutine path is dead code that can be removed.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-9-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
GRAPH_RDLOCK_GUARD() and GRAPH_RDLOCK_GUARD_MAINLOOP() only take a
reader lock for the graph, so the correct annotation for them to use is
TSA_ASSERT_SHARED rather than TSA_ASSERT.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230504115750.54437-8-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
For some functions, it is part of their interface to be called without
holding the graph lock. Add a new macro to document this.
The macro expands to TSA_EXCLUDES(), which is a relatively weak check
because it passes in cases where the compiler just doesn't know if the
lock is held. Function pointers can't be checked at all. Therefore, its
primary purpose is documentation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-7-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
test-bdrv-drain contains a few test cases that are run both in coroutine
and non-coroutine context. Running the entire code including the setup
and shutdown in coroutines is incorrect because graph modifications can
generally not happen in coroutines.
Change the test so that creating and destroying the test nodes and
BlockBackends always happens outside of coroutine context.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230504115750.54437-6-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This tests that trying to resize an image with QMP block_resize doesn't
hang or otherwise fail when the image is attached to a device running in
an iothread.
This is a regression test for the recent fix that changed
qmp_block_resize, which is a coroutine based QMP handler, to avoid
calling no_coroutine_fns directly.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230509134133.373408-1-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This QMP handler runs in a coroutine, so it must use the corresponding
no_co_wrappers instead.
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=2185688
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-5-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
These functions must not be called in coroutine context, because they
need write access to the graph.
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-4-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Migration code can call bdrv_activate() in coroutine context, whereas
other callers call it outside of coroutines. As it calls other code that
is not supposed to run in coroutines, standardise on running outside of
coroutines.
This adds a no_co_wrapper to switch to the main loop before calling
bdrv_activate().
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-3-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There is a bdrv_co_getlength() now, which should be used in coroutine
context.
This requires adding GRAPH_RDLOCK to some functions so that this still
compiles with TSA because bdrv_co_getlength() is GRAPH_RDLOCK.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230504115750.54437-2-kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Commit fe904ea824 added a fail_inactivate label, which tries to
reactivate disks on the source after a failure while s->state ==
MIGRATION_STATUS_ACTIVE, but didn't actually use the label if
qemu_savevm_state_complete_precopy() failed. This failure to
reactivate is also present in commit 6039dd5b1c (also covering the new
s->state == MIGRATION_STATUS_DEVICE state) and 403d18ae (ensuring
s->block_inactive is set more reliably).
Consolidate the two labels back into one - no matter HOW migration is
failed, if there is any chance we can reach vm_start() after having
attempted inactivation, it is essential that we have tried to restart
disks before then. This also makes the cleanup more like
migrate_fd_cancel().
Suggested-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20230502205212.134680-1-eblake@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Socket paths need to be short to avoid failures. This is why there is a
iotests.sock_dir (defaulting to /tmp) separate from the disk image base
directory.
Make use of it to fix failures in too deeply nested test directories.
Fixes: ab7f7e67a7
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230503165019.8867-1-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
job_cancel_locked() drops the job list lock temporarily and it may call
aio_poll(). We must assume that the list has changed after this call.
Also, with unlucky timing, it can end up freeing the job during
job_completed_txn_abort_locked(), making the job pointer invalid, too.
For both reasons, we can't just continue at block_job_next_locked(job).
Instead, start at the head of the list again after job_cancel_locked()
and skip those jobs that we already cancelled (or that are completing
anyway).
Cc: qemu-stable@nongnu.org
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230503140142.474404-1-kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There is no need for the AioContext lock in aio_wait_bh_oneshot().
It's easy to remove the lock from existing callers and then switch from
AIO_WAIT_WHILE() to AIO_WAIT_WHILE_UNLOCKED() in aio_wait_bh_oneshot().
Document that the AioContext lock should not be held across
aio_wait_bh_oneshot(). Holding a lock across aio_poll() can cause
deadlock so we don't want callers to do that.
This is a step towards getting rid of the AioContext lock.
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20230404153307.458883-1-stefanha@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
After the recent introduction of many new coroutine callbacks,
a couple calls from non-coroutine_fn to coroutine_fn have sneaked
in; fix them.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20230406101752.242125-1-pbonzini@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Let's add --enable / --disable configure options for these formats,
so that those who don't need them may not build them.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20230421092758.814122-1-vsementsov@yandex-team.ru>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
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Merge tag 'pull-qapi-2023-05-09-v2' of https://repo.or.cz/qemu/armbru into staging
QAPI patches patches for 2023-05-09
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# gpg: Signature made Wed 10 May 2023 09:05:26 AM BST
# gpg: using RSA key 354BC8B3D7EB2A6B68674E5F3870B400EB918653
# gpg: issuer "armbru@redhat.com"
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>" [undefined]
# gpg: aka "Markus Armbruster <armbru@pond.sub.org>" [undefined]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867 4E5F 3870 B400 EB91 8653
* tag 'pull-qapi-2023-05-09-v2' of https://repo.or.cz/qemu/armbru:
qapi: Reformat doc comments to conform to current conventions
qga/qapi-schema: Reformat doc comments to conform to current conventions
docs/devel/qapi-code-gen: Update doc comment conventions
qapi: Section parameter @indent is no longer used, drop
qapi: Relax doc string @name: description indentation rules
qapi: Rewrite parsing of doc comment section symbols and tags
qapi: Fix argument description indentation stripping
tests/qapi-schema/doc-good: Improve argument description tests
tests/qapi-schema/doc-good: Improve a comment
qapi/dump: Indent bulleted lists consistently
qapi: Tidy up a slightly awkward TODO comment
sphinx/qapidoc: Do not emit TODO sections into user manuals
Revert "qapi: BlockExportRemoveMode: move comments to TODO"
meson: Fix to make QAPI generator output depend on main.py
qapi: Fix crash on stray double quote character
docs/devel/qapi-code-gen: Turn FIXME admonitions into comments
docs/devel/qapi-code-gen: Clean up use of quotes a bit
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
* Add vf-token device option allowing QEMU to assign VFs where the PF
is managed by a userspace driver. (Minwoo Im)
* Skip log_sync during migration setup as a potential source of failure
and likely source of redundancy. (Avihai Horon)
* Virtualize PCIe Resizable BAR capability rather than hiding it,
exposing only the current size as available. (Alex Williamson)
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Merge tag 'vfio-updates-20230509.0' of https://gitlab.com/alex.williamson/qemu into staging
VFIO updates 2023-05-09
* Add vf-token device option allowing QEMU to assign VFs where the PF
is managed by a userspace driver. (Minwoo Im)
* Skip log_sync during migration setup as a potential source of failure
and likely source of redundancy. (Avihai Horon)
* Virtualize PCIe Resizable BAR capability rather than hiding it,
exposing only the current size as available. (Alex Williamson)
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# gpg: Signature made Tue 09 May 2023 09:15:54 PM BST
# gpg: using RSA key 42F6C04E540BD1A99E7B8A90239B9B6E3BB08B22
# gpg: issuer "alex.williamson@redhat.com"
# gpg: Good signature from "Alex Williamson <alex.williamson@redhat.com>" [undefined]
# gpg: aka "Alex Williamson <alex@shazbot.org>" [undefined]
# gpg: aka "Alex Williamson <alwillia@redhat.com>" [undefined]
# gpg: aka "Alex Williamson <alex.l.williamson@gmail.com>" [undefined]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 42F6 C04E 540B D1A9 9E7B 8A90 239B 9B6E 3BB0 8B22
* tag 'vfio-updates-20230509.0' of https://gitlab.com/alex.williamson/qemu:
vfio/pci: Static Resizable BAR capability
vfio/migration: Skip log_sync during migration SETUP state
vfio/pci: add support for VF token
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
This list requires a NULL terminator.
Fixes: 16f5396cec ("target/loongarch: Add LSX data type VReg")
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20230510062405.127260-1-richard.henderson@linaro.org>
Change
# @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed
# do eiusmod tempor incididunt ut labore et dolore magna aliqua.
to
# @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed
# do eiusmod tempor incididunt ut labore et dolore magna aliqua.
See recent commit "qapi: Relax doc string @name: description
indentation rules" for rationale.
Reflow paragraphs to 70 columns width, and consistently use two spaces
to separate sentences.
To check the generated documentation does not change, I compared the
generated HTML before and after this commit with "wdiff -3". Finds no
differences. Comparing with diff is not useful, as the reflown
paragraphs are visible there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-18-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Acked-by: Lukas Straub <lukasstraub2@web.de>
[Straightforward conflicts in qapi/audio.json qapi/misc-target.json
qapi/run-state.json resolved]
Change
# @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed
# do eiusmod tempor incididunt ut labore et dolore magna aliqua.
to
# @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed
# do eiusmod tempor incididunt ut labore et dolore magna aliqua.
See recent commit "qapi: Relax doc string @name: description
indentation rules" for rationale.
Reflow paragraphs to 70 columns width, and consistently use two spaces
to separate sentences.
To check the generated documentation does not change, I compared the
generated HTML before and after this commit with "wdiff -3". Finds no
differences. Comparing with diff is not useful, as the reflown
paragraphs are visible there.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-17-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
The commit before previous relaxed the indentation rules to let us
improve the doc comment conventions. This commit changes the written
conventions. The next commits will update QAPI schemas to conform to
them.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-16-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-15-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
The QAPI schema doc comment language provides special syntax for
command and event arguments, struct and union members, alternate
branches, enumeration values, and features: descriptions starting with
"@name:".
By convention, we format them like this:
# @name: Lorem ipsum dolor sit amet, consectetur adipiscing elit,
# sed do eiusmod tempor incididunt ut labore et dolore
# magna aliqua.
Okay for names as short as "name", but we have much longer ones. Their
description gets squeezed against the right margin, like this:
# @dirty-sync-missed-zero-copy: Number of times dirty RAM synchronization could
# not avoid copying dirty pages. This is between
# 0 and @dirty-sync-count * @multifd-channels.
# (since 7.1)
The description text is effectively just 50 characters wide. Easy
enough to read, but can be cumbersome to write.
The awkward squeeze against the right margin makes people go beyond it,
which produces two undesirables: arguments about style, and descriptions
that are unnecessarily hard to read, like this one:
# @postcopy-vcpu-blocktime: list of the postcopy blocktime per vCPU. This is
# only present when the postcopy-blocktime migration capability
# is enabled. (Since 3.0)
We could instead format it like
# @postcopy-vcpu-blocktime:
# list of the postcopy blocktime per vCPU. This is only present
# when the postcopy-blocktime migration capability is
# enabled. (Since 3.0)
or, since the commit before previous, like
# @postcopy-vcpu-blocktime:
# list of the postcopy blocktime per vCPU. This is only present
# when the postcopy-blocktime migration capability is
# enabled. (Since 3.0)
However, I'd rather have
# @postcopy-vcpu-blocktime: list of the postcopy blocktime per vCPU.
# This is only present when the postcopy-blocktime migration
# capability is enabled. (Since 3.0)
because this is how rST field and option lists work.
To get this, we need to let the first non-blank line after the
"@name:" line determine expected indentation.
This fills up the indentation pitfall mentioned in
docs/devel/qapi-code-gen.rst. A related pitfall still exists. Update
the text to show it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-14-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Work around lack of walrus operator in Python 3.7 and older]
To recognize a line starting with a section symbol and or tag, we
first split it at the first space, then examine the part left of the
space. We can just as well examine the unsplit line, so do that.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20230428105429.1687850-13-armbru@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
[Work around lack of walrus operator in Python 3.7 and older]
* more removal of mb_read/mb_set
* bump _WIN32_WINNT to the Windows 8 API
* fix for modular builds with --disable-system
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Merge tag 'for-upstream' of https://gitlab.com/bonzini/qemu into staging
* target/i386: improved EPYC models
* more removal of mb_read/mb_set
* bump _WIN32_WINNT to the Windows 8 API
* fix for modular builds with --disable-system
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# -----END PGP SIGNATURE-----
# gpg: Signature made Mon 08 May 2023 06:05:00 PM BST
# gpg: using RSA key F13338574B662389866C7682BFFBD25F78C7AE83
# gpg: issuer "pbonzini@redhat.com"
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>" [undefined]
# gpg: aka "Paolo Bonzini <pbonzini@redhat.com>" [undefined]
# gpg: WARNING: This key is not certified with a trusted signature!
# gpg: There is no indication that the signature belongs to the owner.
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4 E2F7 7E15 100C CD36 69B1
# Subkey fingerprint: F133 3857 4B66 2389 866C 7682 BFFB D25F 78C7 AE83
* tag 'for-upstream' of https://gitlab.com/bonzini/qemu:
meson: leave unnecessary modules out of the build
docs: clarify --without-default-devices
target/i386: Add EPYC-Genoa model to support Zen 4 processor series
target/i386: Add VNMI and automatic IBRS feature bits
target/i386: Add missing feature bits in EPYC-Milan model
target/i386: Add feature bits for CPUID_Fn80000021_EAX
target/i386: Add a couple of feature bits in 8000_0008_EBX
target/i386: Add new EPYC CPU versions with updated cache_info
target/i386: allow versioned CPUs to specify new cache_info
include/qemu/osdep.h: Bump _WIN32_WINNT to the Windows 8 API
MAINTAINERS: add stanza for Kconfig files
tb-maint: do not use mb_read/mb_set
call_rcu: stop using mb_set/mb_read
test-aio-multithread: simplify test_multi_co_schedule
test-aio-multithread: do not use mb_read/mb_set for simple flags
rcu: remove qatomic_mb_set, expand comments
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
The PCI Resizable BAR (ReBAR) capability is currently hidden from the
VM because the protocol for interacting with the capability does not
support a mechanism for the device to reject an advertised supported
BAR size. However, when assigned to a VM, the act of resizing the
BAR requires adjustment of host resources for the device, which
absolutely can fail. Linux does not currently allow us to reserve
resources for the device independent of the current usage.
The only writable field within the ReBAR capability is the BAR Size
register. The PCIe spec indicates that when written, the device
should immediately begin to operate with the provided BAR size. The
spec however also notes that software must only write values
corresponding to supported sizes as indicated in the capability and
control registers. Writing unsupported sizes produces undefined
results. Therefore, if the hypervisor were to virtualize the
capability and control registers such that the current size is the
only indicated available size, then a write of anything other than
the current size falls into the category of undefined behavior,
where we can essentially expose the modified ReBAR capability as
read-only.
This may seem pointless, but users have reported that virtualizing
the capability in this way not only allows guest software to expose
related features as available (even if only cosmetic), but in some
scenarios can resolve guest driver issues. Additionally, no
regressions in behavior have been reported for this change.
A caveat here is that the PCIe spec requires for compatibility that
devices report support for a size in the range of 1MB to 512GB,
therefore if the current BAR size falls outside that range we revert
to hiding the capability.
Reviewed-by: Cédric Le Goater <clg@redhat.com>
Link: https://lore.kernel.org/r/20230505232308.2869912-1-alex.williamson@redhat.com
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
