The asynchronous monitor command interface goes back to commit 940cc30
(Jan 2010). Added a third case to command execution. The hope back
then according to the commit message was that all commands get
converted to the asynchronous interface, killing off the other two
cases. Didn't happen.
The initial asynchronous commands balloon and info balloon were
converted back to synchronous long ago (commit 96637bc and d72f32),
with commit messages calling the asynchronous interface "not fully
working" and "deprecated". The only other user went away in commit
3b5704b.
New code generally uses synchronous commands and asynchronous events.
What exactly is still "not fully working" with asynchronous commands?
Well, here's a bug that defeats actual asynchronous use pretty
reliably: the reply's ID is wrong (and has always been wrong) unless
you use the command synchronously! To reproduce, we need an
asynchronous command, so we have to go back before commit 3b5704b.
Run QEMU with spice:
$ qemu-system-x86_64 -nodefaults -S -spice port=5900,disable-ticketing -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 94, "minor": 2, "major": 2}, "package": ""}, "capabilities": []}}
Connect a spice client in another terminal:
$ remote-viewer spice://localhost:5900
Set up a migration destination dummy in a third terminal:
$ socat TCP-LISTEN:12345 STDIO
Now paste the following into the QMP monitor:
{ "execute": "qmp_capabilities", "id": "i0" }
{ "execute": "client_migrate_info", "id": "i1", "arguments": { "protocol": "spice", "hostname": "localhost", "port": 12345 } }
{ "execute": "query-kvm", "id": "i2" }
Produces two replies immediately, one to qmp_capabilities, and one to
query-kvm:
{"return": {}, "id": "i0"}
{"return": {"enabled": false, "present": true}, "id": "i2"}
Both are correct. Two lines of debug output from libspice-server not
shown.
Now EOF socat's standard input to make it close the connection. This
makes the asynchronous client_migrate_info complete. It replies:
{"return": {}}
Bug: "id": "i1" is missing. Two lines of debug output from
libspice-server not shown. Cherry on top: storage for the missing ID
is leaked.
Get rid of this stuff before somebody hurts himself with it.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Luiz Capitulino <lcapitulino@redhat.com>
The functions ringbuf_read_completion() and monitor_get_rs()
are not used anywhere anymore, so let's remove them.
Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Cc: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
monitor_handle_fd_param() is a wrapper around
monitor_handle_fd_param2() that feeds errors to qerror_report_err()
instead of returning them. qerror_report_err() is inappropriate in
many contexts. monitor_handle_fd_param() looks simpler than
monitor_handle_fd_param2(), which tempts use. Remove the temptation:
drop the wrapper and open-code the (trivial) error handling instead.
Replace the open-coded qerror_report_err() by error_report_err() in
places that already use error_report(). Turns out that's everywhere.
While there, rename monitor_handle_fd_param2() to monitor_fd_param().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
I'll use it with block backends shortly, and the name is going to fit
badly there. It's a block layer thing anyway, not just a block driver
thing.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The function monitor_fdset_dup_fd_find_remove() references member of
'mon_fdset' which - when remove flag is set - may be freed in function
monitor_fdset_cleanup().
remove is set by monitor_fdset_dup_fd_remove which in practice
does not need the returned value, so make it void,
and return -1 from monitor_fdset_dup_fd_find_remove.
Reported-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
emits event when ACPI OSPM evaluates _OST method
of ACPI device.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
and rebase monitor_handle_fd_param() to it. (Note that this will slightly
change the behavior when the qemu_parse_fd() branch is selected and it
fails: we now report (and in case of QMP, set) the error immediately,
rather than allowing the caller to set its own error message (if any)).
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
This patchset enables the core of the quorum mechanism.
The num_children reads are compared to get the majority version and if this
version exists more than threshold times the guest won't see the error at all.
If a block is corrupted or if an error occurs during an IO or if the quorum
cannot be established QMP events are used to report to the management.
Use gnutls's SHA-256 to compare versions.
--enable-quorum must be used to enable the feature.
Signed-off-by: Benoit Canet <benoit@irqsave.net>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now that the monitor and readline are decoupled, readline.h no longer
belongs in include/monitor/. Put the header into include/qemu/.
Move the source file into util/ so it can be linked as part of
libqemuutil.a.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add two commands that are the monitor counterparts of -object. The commands
have the same Visitor-based implementation, but use different kinds of
visitors so that the HMP command has a DWIM string-based syntax, while
the QMP variant accepts a stricter JSON-based properties dictionary.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Tested-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Two new functions are added; the first one checks a given range in the
image file for overlaps with metadata (main header, L1 tables, L2
tables, refcount table and blocks).
The second one should be used immediately before writing to the image
file as it calls the first function and, upon collision, marks the
image as corrupt and makes the BDS unusable, thereby preventing
further access.
Both functions take a bitmask argument specifying the structures which
should be checked for overlaps, making it possible to also check
metadata writes against colliding with other structures.
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently macvtap based macvlan device is working in promiscuous
mode, we want to implement mac-programming over macvtap through
Libvirt for better performance.
Design:
QEMU notifies Libvirt when rx-filter config is changed in guest,
then Libvirt query the rx-filter information by a monitor command,
and sync the change to macvtap device. Related rx-filter config
of the nic contains main mac, rx-mode items and vlan table.
This patch adds a QMP event to notify management of rx-filter change,
and adds a monitor command for management to query rx-filter
information.
Test:
If we repeatedly add/remove vlan, and change macaddr of vlan
interfaces in guest by a loop script.
Result:
The events will flood the QMP client(management), management takes
too much resource to process the events.
Event_throttle API (set rate to 1 ms) can avoid the events to flood
QMP client, but it could cause an unexpected delay (~1ms), guests
guests normally expect rx-filter updates immediately.
So we use a flag for each nic to avoid events flooding, the event
is emitted once until the query command is executed. The flag
implementation could not introduce unexpected delay.
There maybe exist an uncontrollable delay if we let Libvirt do the
real change, guests normally expect rx-filter updates immediately.
But it's another separate issue, we can investigate it when the
work in Libvirt side is done.
Michael S. Tsirkin: tweaked to enable events on start
Michael S. Tsirkin: fixed not to crash when no id
Michael S. Tsirkin: fold in patch:
"additional fixes for mac-programming feature"
Amos Kong: always notify QMP client if mactable is changed
Amos Kong: return NULL list if no net client supports rx-filter query
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Amos Kong <akong@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This event will be emited when qemu detects guest panic.
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: cf0bc45ecf9ecd3699bc72dc39f8cbab8ed79d8c.1366945969.git.hutao@cn.fujitsu.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
libvirt has a long-standing bug: when removing the device,
it can request removal but does not know when the
removal completes. Add an event so we can fix this in a robust way.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>