Rename cpu_physical_memory_write_rom_internal() to
address_space_write_rom_internal(), and make it take
MemTxAttrs and return a MemTxResult. This brings its
API into line with address_space_write().

This is an internal function to exec.c; fixing its API
will allow us to change the global function
cpu_physical_memory_write_rom().
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Message-id: 20181122133507.30950-2-peter.maydell@linaro.org

We now require Linux-kernel-style multiline comments:
    /*
     * line one
     * line two
     */

Enforce this in checkpatch.pl, by backporting the relevant
parts of the Linux kernel's checkpatch.pl. (The only changes
needed are that Linux's checkpatch.pl WARN() function takes
an extra argument that ours does not, and the kernel has a
special case for networking code we don't want.)"

The kernel's checkpatch does not enforce "leading /* on
a line of its own, so that part is unique to QEMU's checkpatch.

Sample warning output:

WARNING: Block comments use a leading /* on a separate line
#34: FILE: hw/intc/arm_gicv3_common.c:39:
+    /* Older versions of QEMU had a bug in the handling of state save/restore
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Acked-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>

- Explicitly check for minimum compiler versions
- Remove obsolete code for old compilers that is now not required anymore
- Fix a duplicated typedef for Clang 3.4

# gpg: Signature made Wed 12 Dec 2018 09:05:50 GMT
# gpg:                using RSA key 2ED9D774FE702DB5
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>"
# gpg:                 aka "Thomas Huth <thuth@redhat.com>"
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>"
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>"
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* remotes/huth-gitlab/tags/pull-request-2018-12-12:
  i2c: Move typedef of bitbang_i2c_interface to i2c.h
  Remove QEMU_ARTIFICIAL macro
  includes: Replace QEMU_GNUC_PREREQ with "__has_builtin || !defined(__clang__)"
  audio/alsaaudio: Remove compiler check around pragma
  tcg/tcg.h: Remove GCC check for tcg_debug_assert() macro
  configure: Remove old -fno-gcse workaround for GCC 4.6.x and 4.7.[012]
  configure: Remove obsolete check for Clang < 3.2
  configure: Add a test for the minimum compiler version
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Merge crypto patches 2018/12/12

 - Fix documentation about default LUKS algorithms
 - Support for multi-threaded block crypto

# gpg: Signature made Wed 12 Dec 2018 11:21:52 GMT
# gpg:                using RSA key BE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange/tags/qcrypto-next-pull-request:
  crypto: support multiple threads accessing one QCryptoBlock
  crypto/block: introduce qcrypto_block_*crypt_helper functions
  crypto/block: rename qcrypto_block_*crypt_helper
  crypto/block: refactor qcrypto_block_*crypt_helper functions
  crypto/block-luks: fix memory leak in qcrypto_block_luks_create
  crypto: Fix defaults in QCryptoBlockCreateOptionsLUKS
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Pull request

Minor tracing improvements.

# gpg: Signature made Wed 12 Dec 2018 10:15:30 GMT
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/tracing-pull-request:
  trace: simple style changes
  tracetool: Include thread id information in log backend
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Monitor patches for 2018-12-12

# gpg: Signature made Wed 12 Dec 2018 10:08:15 GMT
# gpg:                using RSA key 3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-monitor-2018-12-12:
  tests: add oob functional test for test-qmp-cmds
  Revert "tests: Add parameter to qtest_init_without_qmp_handshake"
  monitor: Remove "x-oob", offer capability "oob" unconditionally
  monitor: Suspend monitor instead dropping commands
  monitor: avoid potential dead-lock when cleaning up
  monitor: prevent inserting new monitors after cleanup
  colo: check chardev can switch context
  monitor: check if chardev can switch gcontext for OOB
  char: add a QEMU_CHAR_FEATURE_GCONTEXT flag
  monitor: accept chardev input from iothread
  monitor: inline ambiguous helper functions
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

s390x patches for 4.0:
- add 4.0 machine type
- various fixes and small changes

# gpg: Signature made Wed 12 Dec 2018 09:52:04 GMT
# gpg:                using RSA key DECF6B93C6F02FAF
# gpg: Good signature from "Cornelia Huck <conny@cornelia-huck.de>"
# gpg:                 aka "Cornelia Huck <huckc@linux.vnet.ibm.com>"
# gpg:                 aka "Cornelia Huck <cornelia.huck@de.ibm.com>"
# gpg:                 aka "Cornelia Huck <cohuck@kernel.org>"
# gpg:                 aka "Cornelia Huck <cohuck@redhat.com>"
# Primary key fingerprint: C3D0 D66D C362 4FF6 A8C0  18CE DECF 6B93 C6F0 2FAF

* remotes/cohuck/tags/s390x-20181212:
  hw/s390x/virtio-ccw.c: Don't take address of fields in packed structs
  vfio-ap: flag as compatible with balloon
  s390x/tod: Properly stop the KVM TOD while the guest is not running
  s390/MAINTAINERS: Add Halil as kvm and machine maintainer
  s390x: introduce 4.0 compat machine
  s390x/zpci: drop msix.available
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Pull request

Minor virtio-blk fixes.

# gpg: Signature made Wed 12 Dec 2018 09:50:17 GMT
# gpg:                using RSA key 9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>"
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>"
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha/tags/block-pull-request:
  virtio-blk: fix comment for virtio_blk_rw_complete as nalloc is initially -1
  virtio-blk: rename iov to out_iov in virtio_blk_handle_request()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Merge tpm 2018/12/04 v1

# gpg: Signature made Tue 04 Dec 2018 15:25:52 GMT
# gpg:                using RSA key 75AD65802A0B4211
# gpg: Good signature from "Stefan Berger <stefanb@linux.vnet.ibm.com>"
# 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: B818 B9CA DF90 89C2 D5CE  C66B 75AD 6580 2A0B 4211

* remotes/stefanberger/tags/pull-tpm-2018-12-04-1:
  tpm: Make sure the locality received from backend is valid
  tpm: Make sure new locality passed to tpm_tis_prep_abort() is valid
  tpm: Remove unused locty parameter from tpm_tis_abort()
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

x86 queue, 2018-12-11

* New CPU features: MOVDIRI, MOVDIR64B (Liu Jingqi);
  STIBP (Eduardo Habkost)
* Fix clang build warning (Peter Maydell)

# gpg: Signature made Tue 11 Dec 2018 20:52:56 GMT
# gpg:                using RSA key 2807936F984DC5A6
# gpg: Good signature from "Eduardo Habkost <ehabkost@redhat.com>"
# Primary key fingerprint: 5A32 2FD5 ABC4 D3DB ACCF  D1AA 2807 936F 984D C5A6

* remotes/ehabkost/tags/x86-next-pull-request:
  i386: Add "stibp" flag name
  target/i386/kvm.c: Don't mark cpuid_data as QEMU_PACKED
  x86/cpu: Enable MOVDIR64B cpu feature
  x86/cpu: Enable MOVDIRI cpu feature
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The two thing that should be handled are cipher and ivgen. For ivgen
the solution is just mutex, as iv calculations should not be long in
comparison with encryption/decryption. And for cipher let's just keep
per-thread ciphers.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Introduce QCryptoBlock-based functions and use them where possible.
This is needed to implement thread-safe encrypt/decrypt operations.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Rename qcrypto_block_*crypt_helper to qcrypto_block_cipher_*crypt_helper,
as it's not about QCryptoBlock. This is needed to introduce
qcrypto_block_*crypt_helper in the next commit, which will have
QCryptoBlock pointer and than will be able to use additional fields of
it, which in turn will be used to implement thread-safe QCryptoBlock
operations.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

qcrypto_block_encrypt_helper and qcrypto_block_decrypt_helper are
almost identical, let's reduce code duplication and simplify further
improvements.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

Free block->cipher and block->ivgen on error path.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

The values specified in the documentation don't match the actual
defaults set in qcrypto_block_luks_create().
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NDaniel P. Berrangé <berrange@redhat.com>

This changes two lines in simple.c that end with a comma, and replaces them
with a semi-colon.
Signed-off-by: NLarry Dewey <ldewey@suse.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Message-id: 20181127190849.10558-1-ldewey@suse.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Currently the log backend prints the process id of QEMU at the start
of each output line, but since threads share the same PID there is no
clear distinction between their outputs.

Having the thread id present in the log makes it easier to see when
output comes from different threads. E.g.:

12423@1538597569.672527:qemu_mutex_lock waiting on mutex 0x1103ee60 (/root/qemu/util/main-loop.c:236)
...
12430@1538597569.503928:qemu_mutex_unlock released mutex 0x1103ee60 (/root/qemu/cpus.c:1238)
12431@1538597569.503937:qemu_mutex_locked taken mutex 0x1103ee60 (/root/qemu/cpus.c:1257)
^here

In the above, 12423 is the main process id and 12430 & 12431 are the
two vcpu threads.

 (qemu) info cpus
 * CPU #0: thread_id=12430
   CPU #1: thread_id=12431
Suggested-by: NMurilo Opsfelder Araujo <muriloo@linux.ibm.com>
Signed-off-by: NFabiano Rosas <farosas@linux.ibm.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Taking the address of a field in a packed struct is a bad idea, because
it might not be actually aligned enough for that pointer type (and
thus cause a crash on dereference on some host architectures). Newer
versions of clang warn about this. Avoid the bug by not using the
"modify in place" byte swapping functions.

Patch produced with scripts/coccinelle/inplace-byteswaps.cocci
(with a couple of long lines manually wrapped).
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-Id: <20181210120436.30522-1-peter.maydell@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NHalil Pasic <pasic@linux.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

vfio-ap devices do not pin any pages in the host. Therefore, they
are compatible with memory ballooning.

Flag them as compatible, so both vfio-ap and a balloon can be
used simultaneously.

Cc: qemu-stable@nongnu.org
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Tested-by: NTony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: NHalil Pasic <pasic@linux.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Just like on other architectures, we should stop the clock while the guest
is not running. This is already properly done for TCG. Right now, doing an
offline migration (stop, migrate, cont) can easily trigger stalls in the
guest.

Even doing a
    (hmp) stop
    ... wait 2 minutes ...
    (hmp) cont
will already trigger stalls.

So whenever the guest stops, backup the KVM TOD. When continuing to run
the guest, restore the KVM TOD.

One special case is starting a simple VM: Reading the TOD from KVM to
stop it right away until the guest is actually started means that the
time of any simple VM will already differ to the host time. We can
simply leave the TOD running and the guest won't be able to recognize
it.

For migration, we actually want to keep the TOD stopped until really
starting the guest. To be able to catch most errors, we should however
try to set the TOD in addition to simply storing it. So we can still
catch basic migration problems.

If anything goes wrong while backing up/restoring the TOD, we have to
ignore it (but print a warning). This is then basically a fallback to
old behavior (TOD remains running).

I tested this very basically with an initrd:
    1. Start a simple VM. Observed that the TOD is kept running. Old
       behavior.
    2. Ordinary live migration. Observed that the TOD is temporarily
       stopped on the destination when setting the new value and
       correctly started when finally starting the guest.
    3. Offline live migration. (stop, migrate, cont). Observed that the
       TOD will be stopped on the source with the "stop" command. On the
       destination, the TOD is temporarily stopped when setting the new
       value and correctly started when finally starting the guest via
       "cont".
    4. Simple stop/cont correctly stops/starts the TOD. (multiple stops
       or conts in a row have no effect, so works as expected)

In the future, we might want to send the guest a special kind of time sync
interrupt under some conditions, so it can synchronize its tod to the
host tod. This is interesting for migration scenarios but also when we
get time sync interrupts ourselves. This however will most probably have
to be handled in KVM (e.g. when the tods differ too much) and is not
desired e.g. when debugging the guest (single stepping should not
result in permanent time syncs). I consider something like that an add-on
on top of this basic "don't break the guest" handling.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20181130094957.4121-1-david@redhat.com>
Acked-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Halil does more work in this area than I do right now. Lets add Halil.
Signed-off-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Message-Id: <20181204133802.100998-1-borntraeger@de.ibm.com>
Acked-by: NHalil Pasic <pasic@linux.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Reviewed-by: NDavid Hildenbrand <david@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

I fail to see why this is useful as we require MSIX always and
completely fail adding a device.
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20181105110313.29312-2-david@redhat.com>
Fixes: 4f6482bfReviewed-by: NThomas Huth <thuth@redhat.com>
Reviewed-by: NCollin Walling <walling@linux.ibm.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

Straightforward test just to let the test-qmp-cmds be complete.
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-6-peterx@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

This reverts commit ddee57e0.

Meanwhile, revert one line from fa198ad9 to make sure
qtest_init_without_qmp_handshake() will only pass in one parameter.
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-5-peterx@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

Out-of-band command execution was introduced in commit cf869d53.
Unfortunately, we ran into a regression, and had to turn it into an
experimental option for 2.12 (commit be933ffc).

  http://lists.gnu.org/archive/html/qemu-devel/2018-03/msg06231.html

The regression has since been fixed (commit 951702f3 "monitor: bind
dispatch bh to iohandler context").  A thorough re-review of OOB
commands led to a few more issues, which have also been addressed.

This patch partly reverts be933ffc (monitor: new parameter "x-oob"),
and makes QMP monitors again offer capability "oob" whenever they can
provide it, i.e. when the monitor's character device is capable of
running in an I/O thread.

Some trivial touch-up in the test code is required to make sure qmp-test
won't break.
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-4-peterx@redhat.com>
[Conflict with "monitor: check if chardev can switch gcontext for OOB"
resolved, commit message updated]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

The initial value of nalloc is -1, but not 1.
Signed-off-by: NDongli Zhang <dongli.zhang@oracle.com>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>
Message-id: 1541479952-32355-1-git-send-email-dongli.zhang@oracle.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

In virtio_blk_handle_request(), in_iov is used for input header while iov
is used for output header. Rename iov to out_iov to pair output header's
name with in_iov to avoid confusing people when reading source code.
Signed-off-by: NDongli Zhang <dongli.zhang@oracle.com>
Message-id: 1541520556-8334-1-git-send-email-dongli.zhang@oracle.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Clang 3.4 considers duplicate typedef in ppc4xx_i2c.h and
bitbang_i2c.h an error even if they are identical. Move it to a common
place to allow building with this clang version.
Reported-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NBALATON Zoltan <balaton@eik.bme.hu>
Acked-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NThomas Huth <thuth@redhat.com>

The code that used it has already been removed a while ago with commit
dc41aa7d ("tcg: Remove GET_TCGV_* and MAKE_TCGV_*").
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>

Since we require GCC version 4.8 or newer now, we can be sure that
the builtin functions are always available on GCC. And for Clang,
we can check the availablility with __has_builtin instead.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>

Both GCC v4.8 and Clang v3.4 support the -Waddress option, so we do
not need the compiler version check here anymore.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>

Both GCC v4.8 and Clang v3.4 (our minimum versions) support
__builtin_unreachable(), so we can remove the version check here now.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>

Now that we require at least GCC 4.8, we don't need this als workaround
for 4.6 and 4.7 anymore.
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NThomas Huth <thuth@redhat.com>

When a QMP client sends in-band commands more quickly that we can
process them, we can either queue them without limit (QUEUE), drop
commands when the queue is full (DROP), or suspend receiving commands
when the queue is full (SUSPEND).  None of them is ideal:

* QUEUE lets a misbehaving client make QEMU eat memory without bounds.
Not such a hot idea.

* With DROP, the client has to cope with dropped in-band commands.  To
inform the client, we send a COMMAND_DROPPED event then.  The event is
flawed by design in two ways: it's ambiguous (see commit d621cfe0),
and it brings back the "eat memory without bounds" problem.

* With SUSPEND, the client has to manage the flow of in-band commands to
keep the monitor available for out-of-band commands.

We currently DROP.  Switch to SUSPEND.

Managing the flow of in-band commands to keep the monitor available for
out-of-band commands isn't really hard: just count the number of
"outstanding" in-band commands (commands sent minus replies received),
and if it exceeds the limit, hold back additional ones until it drops
below the limit again.

Note that we need to be careful pairing the suspend with a resume, or
else the monitor will hang, possibly forever.  And here since we need to
make sure both:

     (1) popping request from the req queue, and
     (2) reading length of the req queue

will be in the same critical section, we let the pop function take the
corresponding queue lock when there is a request, then we release the
lock from the caller.
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: NPeter Xu <peterx@redhat.com>
Message-Id: <20181009062718.1914-2-peterx@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

When a monitor is connected to a Spice chardev, the monitor cleanup
can dead-lock:

 #0  0x00007f43446637fd in __lll_lock_wait () at /lib64/libpthread.so.0
 #1  0x00007f434465ccf4 in pthread_mutex_lock () at /lib64/libpthread.so.0
 #2  0x0000556dd79f22ba in qemu_mutex_lock_impl (mutex=0x556dd81c9220 <monitor_lock>, file=0x556dd7ae3648 "/home/elmarco/src/qq/monitor.c", line=645) at /home/elmarco/src/qq/util/qemu-thread-posix.c:66
 #3  0x0000556dd7431bd5 in monitor_qapi_event_queue (event=QAPI_EVENT_SPICE_DISCONNECTED, qdict=0x556dd9abc850, errp=0x7fffb7bbddd8) at /home/elmarco/src/qq/monitor.c:645
 #4  0x0000556dd79d476b in qapi_event_send_spice_disconnected (server=0x556dd98ee760, client=0x556ddaaa8560, errp=0x556dd82180d0 <error_abort>) at qapi/qapi-events-ui.c:149
 #5  0x0000556dd7870fc1 in channel_event (event=3, info=0x556ddad1b590) at /home/elmarco/src/qq/ui/spice-core.c:235
 #6  0x00007f434560a6bb in reds_handle_channel_event (reds=<optimized out>, event=3, info=0x556ddad1b590) at reds.c:316
 #7  0x00007f43455f393b in main_dispatcher_self_handle_channel_event (info=0x556ddad1b590, event=3, self=0x556dd9a7d8c0) at main-dispatcher.c:197
 #8  0x00007f43455f393b in main_dispatcher_channel_event (self=0x556dd9a7d8c0, event=event@entry=3, info=0x556ddad1b590) at main-dispatcher.c:197
 #9  0x00007f4345612833 in red_stream_push_channel_event (s=s@entry=0x556ddae2ef40, event=event@entry=3) at red-stream.c:414
 #10 0x00007f434561286b in red_stream_free (s=0x556ddae2ef40) at red-stream.c:388
 #11 0x00007f43455f9ddc in red_channel_client_finalize (object=0x556dd9bb21a0) at red-channel-client.c:347
 #12 0x00007f434b5f9fb9 in g_object_unref () at /lib64/libgobject-2.0.so.0
 #13 0x00007f43455fc212 in red_channel_client_push (rcc=0x556dd9bb21a0) at red-channel-client.c:1341
 #14 0x0000556dd76081ba in spice_port_set_fe_open (chr=0x556dd9925e20, fe_open=0) at /home/elmarco/src/qq/chardev/spice.c:241
 #15 0x0000556dd796d74a in qemu_chr_fe_set_open (be=0x556dd9a37c00, fe_open=0) at /home/elmarco/src/qq/chardev/char-fe.c:340
 #16 0x0000556dd796d4d9 in qemu_chr_fe_set_handlers (b=0x556dd9a37c00, fd_can_read=0x0, fd_read=0x0, fd_event=0x0, be_change=0x0, opaque=0x0, context=0x0, set_open=true) at /home/elmarco/src/qq/chardev/char-fe.c:280
 #17 0x0000556dd796d359 in qemu_chr_fe_deinit (b=0x556dd9a37c00, del=false) at /home/elmarco/src/qq/chardev/char-fe.c:233
 #18 0x0000556dd7432240 in monitor_data_destroy (mon=0x556dd9a37c00) at /home/elmarco/src/qq/monitor.c:786
 #19 0x0000556dd743b968 in monitor_cleanup () at /home/elmarco/src/qq/monitor.c:4683
 #20 0x0000556dd75ce776 in main (argc=3, argv=0x7fffb7bbe458, envp=0x7fffb7bbe478) at /home/elmarco/src/qq/vl.c:4660

Because spice code tries to emit a "disconnected" signal on the
monitors. Fix this dead-lock by releasing the monitor lock for
flush/destroy.

monitor_lock protects mon_list, monitor_qapi_event_state and
monitor_destroyed. monitor_flush() and monitor_data_destroy() don't
access any of those variables.

monitor_cleanup()'s loop is safe because it uses
QTAILQ_FOREACH_SAFE(), and no further monitor can be added after
calling monitor_cleanup() thanks to monitor_destroyed check in
monitor_list_append().
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-8-marcandre.lureau@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

monitor_cleanup() is one of the last things main() calls before it
returns.  In the following patch, monitor_cleanup() will release the
monitor_lock during flushing. There may be pending commands to insert
new monitors, which would modify the mon_list during iteration, and
the clean-up could thus miss those new insertions.

Add a monitor_destroyed global to check if monitor_cleanup() has been
already called. In this case, don't insert the new monitor in the
list, but free it instead. A cleaner solution would involve the main
thread telling other threads to terminate, waiting for their
termination.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <20181205203737.9011-7-marcandre.lureau@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

COLO uses a worker context (iothread) to drive the chardev. All
backends are not able to switch the context, let's report an error in
this case.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-6-marcandre.lureau@redhat.com>
Reviewed-by: NLi Zhijian <lizhiian@cn.fujitsu.com>
Reviewed-by: NZhang Chen <zhangckid@gmail.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

Not all backends are able to switch gcontext. Those backends cannot
drive a OOB monitor (the monitor would then be blocking on main
thread).

For example, ringbuf, spice, or more esoteric input chardevs like
braille or MUX.

We already forbid MUX because not all frontends are ready to run outside
main loop.  Replace that by a context-switching feature check.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20181205203737.9011-5-marcandre.lureau@redhat.com>
[Error condition simplified, commit message adjusted accordingly]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>