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The new build-previous-qemu job relies on QEMU release tag being present,
while that may not be always true for personal git repositories since by
default tag is not pushed. The job can fail on those CI kicks, as reported
by Peter Maydell.
Fix it by fetching the tags remotely from the official repository, as
suggested by Dan.
[1] https://lore.kernel.org/r/ZcC9ScKJ7VvqektA@redhat.com
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Suggested-by: "Daniel P. Berrangé" <berrange@redhat.com>
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Link: https://lore.kernel.org/r/20240207005403.242235-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Recently we introduced cross-binary migration test. It's always wanted
that migration-test uses stable guest ABI for both QEMU binaries in this
case, so that both QEMU binaries will be compatible on the migration
stream with the cmdline specified.
Switch to a static gic version "3" rather than using version "max", so that
GIC should be stable now across any future QEMU binaries for migration-test.
Here the version can actually be anything as long as the ABI is stable. We
choose "3" because it's the majority of what we already use in QEMU while
still new enough: "git grep gic-version=3" shows 6 hit, while version 4 has
no direct user yet besides "max".
Note that even with this change, aarch64 won't be able to work yet with
migration cross binary test, but then the only missing piece will be the
stable CPU model.
Reviewed-by: "Daniel P. Berrangé" <berrange@redhat.com>
Link: https://lore.kernel.org/r/20240207005403.242235-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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It is possible that one of the multifd channels fails to be created at
multifd_new_send_channel_async() while the rest of the channel
creation tasks are still in flight.
This could lead to multifd_save_cleanup() executing the
qemu_thread_join() loop too early and not waiting for the threads
which haven't been created yet, leading to the freeing of resources
that the newly created threads will try to access and crash.
Add a synchronization point after which there will be no attempts at
thread creation and therefore calling multifd_save_cleanup() past that
point will ensure it properly waits for the threads.
A note about performance: Prior to this patch, if a channel took too
long to be established, other channels could finish connecting first
and already start taking load. Now we're bounded by the
slowest-connecting channel.
Reported-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-7-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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During multifd channel creation (multifd_send_new_channel_async) when
TLS is enabled, the multifd_channel_connect function is called twice,
once to create the TLS handshake thread and another time after the
asynchrounous TLS handshake has finished.
This creates a slightly confusing call stack where
multifd_channel_connect() is called more times than the number of
channels. It also splits error handling between the two callers of
multifd_channel_connect() causing some code duplication. Lastly, it
gets in the way of having a single point to determine whether all
channel creation tasks have been initiated.
Refactor the code to move the reentrancy one level up at the
multifd_new_send_channel_async() level, de-duplicating the error
handling and allowing for the next patch to introduce a
synchronization point common to all the multifd channel creation,
regardless of TLS.
Note that the previous code would never fail once p->c had been set.
This patch changes this assumption, which affects refcounting, so add
comments around object_unref to explain the situation.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-6-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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We currently have an unfavorable situation around multifd channels
creation and the migration thread execution.
We create the multifd channels with qio_channel_socket_connect_async
-> qio_task_run_in_thread, but only connect them at the
multifd_new_send_channel_async callback, called from
qio_task_complete, which is registered as a glib event.
So at multifd_send_setup() we create the channels, but they will only
be actually usable after the whole multifd_send_setup() calling stack
returns back to the main loop. Which means that the migration thread
is already up and running without any possibility for the multifd
channels to be ready on time.
We currently rely on the channels-ready semaphore blocking
multifd_send_sync_main() until channels start to come up and release
it. However there have been bugs recently found when a channel's
creation fails and multifd_send_cleanup() is allowed to run while
other channels are still being created.
Let's start to organize this situation by moving the
multifd_send_setup() call into the migration thread. That way we
unblock the main-loop to dispatch the completion callbacks and
actually have a chance of getting the multifd channels ready for when
the migration thread needs them.
The next patches will deal with the synchronization aspects.
Note that this takes multifd_send_setup() out of the BQL.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-5-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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Hide the error handling inside multifd_send_setup to make it cleaner
for the next patch to move the function around.
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-4-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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We currently only need p->running to avoid calling qemu_thread_join()
on a non existent thread if the thread has never been created.
However, there are at least two bugs in this logic:
1) On the sending side, p->running is set too early and
qemu_thread_create() can be skipped due to an error during TLS
handshake, leaving the flag set and leading to a crash when
multifd_send_cleanup() calls qemu_thread_join().
2) During exit, the multifd thread clears the flag while holding the
channel lock. The counterpart at multifd_send_cleanup() reads the flag
outside of the lock and might free the mutex while the multifd thread
still has it locked.
Fix the first issue by setting the flag right before creating the
thread. Rename it from p->running to p->thread_created to clarify its
usage.
Fix the second issue by not clearing the flag at the multifd thread
exit. We don't have any use for that.
Note that these bugs are straight-forward logic issues and not race
conditions. There is still a gap for races to affect this code due to
multifd_send_cleanup() being allowed to run concurrently with the
thread creation loop. This issue is solved in the next patches.
Cc: qemu-stable <qemu-stable@nongnu.org>
Fixes: 29647140157a ("migration/tls: add support for multifd tls-handshake")
Reported-by: Avihai Horon <avihaih@nvidia.com>
Reported-by: chenyuhui5@huawei.com
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-3-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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We're currently leaking the resources of the TLS thread by not joining
it and also overwriting the p->thread pointer altogether.
Fixes: a1af605bd5 ("migration/multifd: fix hangup with TLS-Multifd due to blocking handshake")
Cc: qemu-stable <qemu-stable@nongnu.org>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240206215118.6171-2-farosas@suse.de
Signed-off-by: Peter Xu <peterx@redhat.com>
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The commit in the fixes line mistakenly modified the channels and
transport compatibility check logic so it now checks multi-channel
support only for socket transport type.
Thus, running multifd migration using a transport other than socket that
is incompatible with multi-channels (such as "exec") would lead to a
segmentation fault instead of an error message.
For example:
(qemu) migrate_set_capability multifd on
(qemu) migrate -d "exec:cat > /tmp/vm_state"
Segmentation fault (core dumped)
Fix it by checking multi-channel compatibility for all transport types.
Cc: qemu-stable <qemu-stable@nongnu.org>
Fixes: d95533e1cdcc ("migration: modify migration_channels_and_uri_compatible() for new QAPI syntax")
Signed-off-by: Avihai Horon <avihaih@nvidia.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20240125162528.7552-2-avihaih@nvidia.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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When reviewing my attempt to refactor send_prepare(), Fabiano suggested we
try out with dropping the mutex in multifd code [1].
I thought about that before but I never tried to change the code. Now
maybe it's time to give it a stab. This only optimizes the sender side.
The trick here is multifd has a clear provider/consumer model, that the
migration main thread publishes requests (either pending_job/pending_sync),
while the multifd sender threads are consumers. Here we don't have a lot
of complicated data sharing, and the jobs can logically be submitted
lockless.
Arm the code with atomic weapons. Two things worth mentioning:
- For multifd_send_pages(): we can use qatomic_load_acquire() when trying
to find a free channel, but that's expensive if we attach one ACQUIRE per
channel. Instead, keep the qatomic_read() on reading the pending_job
flag as we do already, meanwhile use one smp_mb_acquire() after the loop
to guarantee the memory ordering.
- For pending_sync: it doesn't have any extra data required since now
p->flags are never touched, it should be safe to not use memory barrier.
That's different from pending_job.
Provide rich comments for all the lockless operations to state how they are
paired. With that, we can remove the mutex.
[1] https://lore.kernel.org/r/87o7d1jlu5.fsf@suse.de
Suggested-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-24-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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As reported correctly by Fabiano [1] (while per Fabiano, it sourced back to
Elena's initial report in Oct 2023), MultiFDSendParams.packet_num is buggy
to be assigned and stored. Consider two consequent operations of: (1)
queue a job into multifd send thread X, then (2) queue another sync request
to the same send thread X. Then the MultiFDSendParams.packet_num will be
assigned twice, and the first assignment can get lost already.
To avoid that, we move the packet_num assignment from p->packet_num into
where the thread will fill in the packet. Use atomic operations to protect
the field, making sure there's no race.
Note that atomic fetch_add() may not be good for scaling purposes, however
multifd should be fine as number of threads should normally not go beyond
16 threads. Let's leave that concern for later but fix the issue first.
There's also a trick on how to make it always work even on 32 bit hosts for
uint64_t packet number. Switching to uintptr_t as of now to simply the
case. It will cause packet number to overflow easier on 32 bit, but that
shouldn't be a major concern for now as 32 bit systems is not the major
audience for any performance concerns like what multifd wants to address.
We also need to move multifd_send_state definition upper, so that
multifd_send_fill_packet() can reference it.
[1] https://lore.kernel.org/r/87o7d1jlu5.fsf@suse.de
Reported-by: Elena Ufimtseva <elena.ufimtseva@oracle.com>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-23-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Most of the multifd code uses send/recv to represent the two sides, but
some rare cases use save/load.
Since send/recv is the majority, replacing the save/load use cases to use
send/recv globally. Now we reach a consensus on the naming.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-22-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Use similar logic to cleanup the recv side.
Note that multifd_recv_terminate_threads() may need some similar rework
like the sender side, but let's leave that for later.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-21-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Shrink the function by moving relevant works into helpers: move the thread
join()s into multifd_send_terminate_threads(), then create two more helpers
to cover channel/state cleanups.
Add a TODO entry for the thread terminate process because p->running is
still buggy. We need to fix it at some point but not yet covered.
Suggested-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-20-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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The current multifd_queue_page() is not easy to read and follow. It is not
good with a few reasons:
- No helper at all to show what exactly does a condition mean; in short,
readability is low.
- Rely on pages->ramblock being cleared to detect an empty queue. It's
slightly an overload of the ramblock pointer, per Fabiano [1], which I
also agree.
- Contains a self recursion, even if not necessary..
Rewrite this function. We add some comments to make it even clearer on
what it does.
[1] https://lore.kernel.org/r/87wmrpjzew.fsf@suse.de
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-19-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Using int is an overkill when there're only two options. Change it to a
boolean.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-18-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Using int is an overkill when there're only two options. Change it to a
boolean.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-17-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Split multifd_send_terminate_threads() into two functions:
- multifd_send_set_error(): used when an error happened on the sender
side, set error and quit state only
- multifd_send_terminate_threads(): used only by the main thread to kick
all multifd send threads out of sleep, for the last recycling.
Use multifd_send_set_error() in the three old call sites where only the
error will be set.
Use multifd_send_terminate_threads() in the last one where the main thread
will kick the multifd threads at last in multifd_save_cleanup().
Both helpers will need to set quitting=1.
Suggested-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-16-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Now multifd's logic is designed to have no spurious wakeup. I still
remember a talk to Juan and he seems to agree we should drop it now, and if
my memory was right it was there because multifd used to hit that when
still debugging.
Let's drop it and see what can explode; as long as it's not reaching
soft-freeze.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-15-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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This patch redefines the interfacing of ->send_prepare(). It further
simplifies multifd_send_thread() especially on zero copy.
Now with the new interface, we require the hook to do all the work for
preparing the IOVs to send. After it's completed, the IOVs should be ready
to be dumped into the specific multifd QIOChannel later.
So now the API looks like:
p->pages -----------> send_prepare() -------------> IOVs
This also prepares for the case where the input can be extended to even not
any p->pages. But that's for later.
This patch will achieve similar goal of what Fabiano used to propose here:
https://lore.kernel.org/r/20240126221943.26628-1-farosas@suse.de
However the send() interface may not be necessary. I'm boldly attaching a
"Co-developed-by" for Fabiano.
Co-developed-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-14-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Introduce a helper multifd_send_prepare_header() to setup the header packet
for multifd sender.
It's fine to setup the IOV[0] _before_ send_prepare() because the packet
buffer is already ready, even if the content is to be filled in.
With this helper, we can already slightly clean up the zero copy path.
Note that I explicitly put it into multifd.h, because I want it inlined
directly into multifd*.c where necessary later.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-13-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Move them into fill/unfill of packets. With that, we can further cleanup
the send/recv thread procedure, and remove one more temp var.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-12-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Just like the previous patch, move the accounting for total_normal_pages on
both src/dst sides into the packet fill/unfill procedures.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-11-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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This field, no matter whether on src or dest, is only used for debugging
purpose.
They can even be removed already, unless it still more or less provide some
accounting on "how many packets are sent/recved for this thread". The
other more important one is called packet_num, which is embeded in the
multifd packet headers (MultiFDPacket_t).
So let's keep them for now, but make them much easier to understand, by
doing below:
- Rename both of them to packets_sent / packets_recved, the old
name (num_packets) are waaay too confusing when we already have
MultiFDPacket_t.packets_num.
- Avoid worrying on the "initial packet": we know we will send it, that's
good enough. The accounting won't matter a great deal to start with 0 or
with 1.
- Move them to where we send/recv the packets. They're:
- multifd_send_fill_packet() for senders.
- multifd_recv_unfill_packet() for receivers.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-10-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Now with a split SYNC handler, we always have pages->num set for
pending_job==true. Assert it instead.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-9-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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The sender thread will yield the p->mutex before IO starts, trying to not
block the requester thread. This may be unnecessary lock optimizations,
because the requester can already read pending_job safely even without the
lock, because the requester is currently the only one who can assign a
task.
Drop that lock complication on both sides:
(1) in the sender thread, always take the mutex until job done
(2) in the requester thread, check pending_job clear lockless
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-8-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Multifd provide a threaded model for processing jobs. On sender side,
there can be two kinds of job: (1) a list of pages to send, or (2) a sync
request.
The sync request is a very special kind of job. It never contains a page
array, but only a multifd packet telling the dest side to synchronize with
sent pages.
Before this patch, both requests use the pending_job field, no matter what
the request is, it will boost pending_job, while multifd sender thread will
decrement it after it finishes one job.
However this should be racy, because SYNC is special in that it needs to
set p->flags with MULTIFD_FLAG_SYNC, showing that this is a sync request.
Consider a sequence of operations where:
- migration thread enqueue a job to send some pages, pending_job++ (0->1)
- [...before the selected multifd sender thread wakes up...]
- migration thread enqueue another job to sync, pending_job++ (1->2),
setup p->flags=MULTIFD_FLAG_SYNC
- multifd sender thread wakes up, found pending_job==2
- send the 1st packet with MULTIFD_FLAG_SYNC and list of pages
- send the 2nd packet with flags==0 and no pages
This is not expected, because MULTIFD_FLAG_SYNC should hopefully be done
after all the pages are received. Meanwhile, the 2nd packet will be
completely useless, which contains zero information.
I didn't verify above, but I think this issue is still benign in that at
least on the recv side we always receive pages before handling
MULTIFD_FLAG_SYNC. However that's not always guaranteed and just tricky.
One other reason I want to separate it is using p->flags to communicate
between the two threads is also not clearly defined, it's very hard to read
and understand why accessing p->flags is always safe; see the current impl
of multifd_send_thread() where we tried to cache only p->flags. It doesn't
need to be that complicated.
This patch introduces pending_sync, a separate flag just to show that the
requester needs a sync. Alongside, we remove the tricky caching of
p->flags now because after this patch p->flags should only be used by
multifd sender thread now, which will be crystal clear. So it is always
thread safe to access p->flags.
With that, we can also safely convert the pending_job into a boolean,
because we don't support >1 pending jobs anyway.
Always use atomic ops to access both flags to make sure no cache effect.
When at it, drop the initial setting of "pending_job = 0" because it's
always allocated using g_new0().
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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This array is redundant when p->pages exists. Now we extended the life of
p->pages to the whole period where pending_job is set, it should be safe to
always use p->pages->offset[] rather than p->normal[]. Drop the array.
Alongside, the normal_num is also redundant, which is the same to
p->pages->num.
This doesn't apply to recv side, because there's no extra buffering on recv
side, so p->normal[] array is still needed.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-6-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Now we reset MultiFDPages_t object in the multifd sender thread in the
middle of the sending job. That's not necessary, because the "*pages"
struct will not be reused anyway until pending_job is cleared.
Move that to the end after the job is completed, provide a helper to reset
a "*pages" object. Use that same helper when free the object too.
This prepares us to keep using p->pages in the follow up patches, where we
may drop p->normal[].
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Multifd send side has two fields to indicate error quits:
- MultiFDSendParams.quit
- &multifd_send_state->exiting
Merge them into the global one. The replacement is done by changing all
p->quit checks into the global var check. The global check doesn't need
any lock.
A few more things done on top of this altogether:
- multifd_send_terminate_threads()
Moving the xchg() of &multifd_send_state->exiting upper, so as to cover
the tracepoint, migrate_set_error() and migrate_set_state().
- multifd_send_sync_main()
In the 2nd loop, add one more check over the global var to make sure we
don't keep the looping if QEMU already decided to quit.
- multifd_tls_outgoing_handshake()
Use multifd_send_terminate_threads() to set the error state. That has
a benefit of updating MigrationState.error to that error too, so we can
persist that 1st error we hit in that specific channel.
- multifd_new_send_channel_async()
Take similar approach like above, drop the migrate_set_error() because
multifd_send_terminate_threads() already covers that. Unwrap the helper
multifd_new_send_channel_cleanup() along the way; not really needed.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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When a multifd sender thread hit errors, it always needs to kick the main
thread by kicking all the semaphores that it can be waiting upon.
Provide a helper for it and deduplicate the code.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-3-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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We've already done that with multifd_flush_after_each_section, for multifd
in general. Drop the stale "TODO-like" comment.
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Link: https://lore.kernel.org/r/20240202102857.110210-2-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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A memory page poisoned from the hypervisor level is no longer readable.
The migration of a VM will crash Qemu when it tries to read the
memory address space and stumbles on the poisoned page with a similar
stack trace:
Program terminated with signal SIGBUS, Bus error.
#0 _mm256_loadu_si256
#1 buffer_zero_avx2
#2 select_accel_fn
#3 buffer_is_zero
#4 save_zero_page
#5 ram_save_target_page_legacy
#6 ram_save_host_page
#7 ram_find_and_save_block
#8 ram_save_iterate
#9 qemu_savevm_state_iterate
#10 migration_iteration_run
#11 migration_thread
#12 qemu_thread_start
To avoid this VM crash during the migration, prevent the migration
when a known hardware poison exists on the VM.
Signed-off-by: William Roche <william.roche@oracle.com>
Link: https://lore.kernel.org/r/20240130190640.139364-2-william.roche@oracle.com
Signed-off-by: Peter Xu <peterx@redhat.com>
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Documentation of commands guest-ssh-get-authorized-keys,
guest-ssh-add-authorized-keys, and guest-ssh-remove-authorized-keys
describes the command's purpose after its arguments. Everywhere else,
we do it the other way round. Move it for consistency.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240129115008.674248-6-armbru@redhat.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
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Documentation of type BlockdevOptionsIscsi describes the type's
purpose after its members. Everywhere else, we do it the other way
round. Move it for consistency.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240129115008.674248-5-armbru@redhat.com>
Reviewed-by: Konstantin Kostiuk <kkostiuk@redhat.com>
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Documentation of BlockExportRemoveMode has
Potential additional modes to be added in the future:
hide: Just hide export from new clients, leave existing connections
as is. Remove export after all clients are disconnected.
soft: Hide export from new clients, answer with ESHUTDOWN for all
further requests from existing clients.
I think this is useful only for developers. Elide it from generated
documentation by turning it into a TODO section.
This effectively reverts my own commit b71fd73cc45 (Revert "qapi:
BlockExportRemoveMode: move comments to TODO"). At the time, I was
about to elide TODO sections from the generated manual, I wasn't sure
about this one, and decided to avoid change. And now I've made up my
mind.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240129115008.674248-4-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
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Documentation generated for dump-skeys contains
This command is only supported on s390 architecture.
and
If
~~
"TARGET_S390X"
The former became redundant in commit 901a34a400a (qapi: add 'If:'
section to generated documentation) added the latter. Drop the
former.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240129115008.674248-3-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
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Documentation generated for SchemaInfo looks like
The members of "SchemaInfoBuiltin" when "meta-type" is ""builtin""
The members of "SchemaInfoEnum" when "meta-type" is ""enum""
The members of "SchemaInfoArray" when "meta-type" is ""array""
The members of "SchemaInfoObject" when "meta-type" is ""object""
The members of "SchemaInfoAlternate" when "meta-type" is ""alternate""
The members of "SchemaInfoCommand" when "meta-type" is ""command""
The members of "SchemaInfoEvent" when "meta-type" is ""event""
Additional members depend on the value of "meta-type".
The last line became redundant when commit 88f63467c57 (qapi2texi:
Generate reference to base type members) added the lines preceding it.
Drop it.
BlockdevOptions has the same issue. Drop
Remaining options are determined by the block driver.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-ID: <20240129115008.674248-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
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Without this padding, an unwind through the signal handler
will pick up the unwind info for the preceding syscall.
This fixes gcc's 30_threads/thread/native_handle/cancel.cc.
Cc: qemu-stable@nongnu.org
Fixes: ee95fae075c6 ("linux-user/aarch64: Add vdso")
Resolves: https://linaro.atlassian.net/browse/GNU-974
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20240202034427.504686-1-richard.henderson@linaro.org>
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These macros are no longer used.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-23-richard.henderson@linaro.org>
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Represent each fcc field separately from the rest of fsr.
This vastly simplifies floating-point comparisons.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-22-richard.henderson@linaro.org>
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Drop this field as a tcg global, loading it explicitly in the
few places required. This means that all FPop helpers may
once again be TCG_CALL_NO_WG.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-21-richard.henderson@linaro.org>
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These two fields are adjusted by all FPop insns.
Having them separate makes it easier to set without masking.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-20-richard.henderson@linaro.org>
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If an exception is to be raised, the destination fp register
should be unmodified. The current implementation is incorrect,
in that double results will be written back before calling
gen_helper_check_ieee_exceptions, despite the placement of
gen_store_fpr_D, since gen_dest_fpr_D returns cpu_fpr[].
We can simplify the entire implementation by having each
FPOp helper call check_ieee_exceptions. For the moment this
requires that all FPop helpers write to the TCG global cpu_fsr,
so remove TCG_CALL_NO_WG from the DEF_HELPER_FLAGS_*.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-19-richard.henderson@linaro.org>
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Don't do the clearing explicitly before each FPop,
rather do it as part of the rest of exception handling.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-18-richard.henderson@linaro.org>
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This field is read-only. It is easier to store it separately
and merge it only upon read.
While we're at it, use FSR_VER_SHIFT to initialize fpu_version.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-17-richard.henderson@linaro.org>
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Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-16-richard.henderson@linaro.org>
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These are no longer used for passing data to/from helpers.
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-15-richard.henderson@linaro.org>
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Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-14-richard.henderson@linaro.org>
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Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20231103173841.33651-13-richard.henderson@linaro.org>
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