Macro ERRP_GUARD() is only needed when we want to dereference @errp or
pass it to error_prepend() or error_append_hint(). Delete superfluous
ones.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-15-armbru@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
We did this with scripts/coccinelle/use-error_fatal.cocci before, in
commit 50beeb6809 and 007b06578a. This commit cleans up rarer
variations that don't seem worth matching with Coccinelle.
Cc: Thomas Huth <thuth@redhat.com>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Juan Quintela <quintela@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marc-André Lureau <marcandre.lureau@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210720125408.387910-2-armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Libvirt's "domcapabilities" command has a way to state whether certain
graphic frontends are available in QEMU or not. Originally, libvirt
looked at the "--help" output of the QEMU binary to determine whether
SDL was available or not (by looking for the "-sdl" parameter in the
help text), but since libvirt stopped doing this analysis of the help
text, the detection of SDL is currently broken, see:
https://bugzilla.redhat.com/show_bug.cgi?id=1790902
QEMU should provide a way via the QMP interface instead. A simple way,
without introducing additional commands, is to make the DisplayType
enum entries conditional, so that the enum only contains the entries if
the corresponding CONFIG_xxx switches have been set. This of course
only gives an indication which possibilities have been enabled during
compile-time of QEMU (and does not take into account whether modules
are later available or not for example - for this we'd need a separate
command), but anyway, this should already be good enough for the above
bug ticket, and it's a good idea anyway to make the QMP interface
conditional here, so let's simply do it.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20210615090439.70926-1-thuth@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Follow the inclusive terminology from the "Conscious Language in your
Open Source Projects" guidelines [*] and replace the words "whitelist"
appropriately.
[*] https://github.com/conscious-lang/conscious-lang-docs/blob/main/faq.md
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20210303184644.1639691-2-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
ui/console used to accept NULL as graphic console surface, but its
semantics was inconsistent among displays:
- cocoa and gtk-egl perform NULL dereference.
- egl-headless, spice and spice-egl do nothing.
- gtk releases underlying resources.
- sdl2-2d and sdl2-gl destroys the window.
- vnc shows a message, "Display output is not active."
Fortunately, only virtio-gpu and virtio-gpu-3d assign NULL so
we can study them to figure out the desired behavior. They assign
NULL *except* for the primary display when the device is realized,
reset, or its scanout is disabled. This effectively destroys
windows for the (uninitialized) secondary displays.
To implement the consistent behavior of display device
realization/reset, this change embeds it to the operation
switching the surface. When NULL was given as a new surface when
switching, ui/console will instead passes a placeholder down
to each display listeners.
sdl destroys the window for a secondary console if its surface is a
placeholder. The other displays simply shows the placeholder.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20210225101316.83940-2-akihiko.odaki@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The surfaces created with former qemu_create_message_surface
did not display the content from the guest and always contained
simple messages describing the reason.
A display backend may want to hide the window showing such a
surface. This change renames the function to
qemu_create_placeholder_surface, and adds "placeholder" flag; the
display can check the flag to decide to do anything special like
hiding the window.
Signed-off-by: Akihiko Odaki <akihiko.odaki@gmail.com>
Message-Id: <20210225101316.83940-1-akihiko.odaki@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Displaying rendered resources requires blocking qemu GPU to avoid extra
framebuffer copies. For an external display, via Spice currently, there
is a callback to block/unblock the rendering in the same thread.
But with the vhost-user-gpu backend, the qemu process doesn't handle
the rendering itself, and the blocking callback isn't effective.
Instead, the backend must be notified when the display code is done.
Fix this by adding a new GraphicHwOps callback to indicate the GL state
is flushed, and we are done manipulating the shared GL resources. Call
it from gtk and spice display.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210204105232.834642-19-marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This check is currently limited. It only is used by vhost-user-gpu (not
by vfio-display), and will print an error repeatedly during run-time.
We are going to dissociate the GL context from the
DisplayChangeListener, and listeners may come and go. The following
patches will address this differently.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210204105232.834642-10-marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
There are no users left.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20210204105232.834642-7-marcandre.lureau@redhat.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This commit is the result of running the timer-del-timer-free.cocci
script on the whole source tree.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20201215154107.3255-4-peter.maydell@linaro.org
Generalize the qdev_hotplug variable to the different phases of
machine initialization. We would like to allow different
monitor commands depending on the phase.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use active_console in that case like we do in many other places.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-id: 20201208115737.18581-3-kraxel@redhat.com
Add missing sanity check.
Reproducer: run qemu with "-device qxl" but without "-spice ..."
Fixes: 0d9b90ce5c ("console: make QMP/HMP screendump run in coroutine")
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20201124122936.30588-1-kraxel@redhat.com
In graphic_hw_update(), first select an existing console,
a specific-console or active_console(if not specified),
then updating the console.
Signed-off-by: lichun <lichun@ruijie.com.cn>
Message-id: 1604682219-114389-1-git-send-email-lichun@ruijie.com.cn
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Thanks to the monitors' coroutine support (merge commit b7092cda1b),
the screendump handler can trigger a graphic_hw_update(), yield and let
the main loop run until update is done. Then the handler is resumed, and
ppm_save() will write the screen image to disk in the coroutine context.
The IO is still blocking though, as the file is set blocking so far,
this could be addressed by some future change (with other caveats).
Related to:
https://bugzilla.redhat.com/show_bug.cgi?id=1230527
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: 20201027133602.3038018-4-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The function is going to be called from a coroutine, and may yield.
Let's ensure our image reference doesn't change over time (due to resize
etc) by keeping a ref.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20201027133602.3038018-3-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
./chardev/baum.c expects the default window_id value to be -1, and not 0
which could be confused with a proper window id (when numbered from 0 by
the ui backend).
This fixes getting Braille output with the curses and gtk frontends.
Fixes: f29b3431f6 ("console: move window ID code from baum to sdl")
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20200914100637.eeommoflirxrgaeh@function>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
The following patch is going to introduce extra fields / details to
UIInfo. Add a getter and keep the current values, instead of memset(0)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20200927145751.365446-4-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
We want to introduce a new version of qemu_open() that uses an Error
object for reporting problems and make this it the preferred interface.
Rename the existing method to release the namespace for the new impl.
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Some typedefs and macros are defined after the type check macros.
This makes it difficult to automatically replace their
definitions with OBJECT_DECLARE_TYPE.
Patch generated using:
$ ./scripts/codeconverter/converter.py -i \
--pattern=QOMStructTypedefSplit $(git grep -l '' -- '*.[ch]')
which will split "typdef struct { ... } TypedefName"
declarations.
Followed by:
$ ./scripts/codeconverter/converter.py -i --pattern=MoveSymbols \
$(git grep -l '' -- '*.[ch]')
which will:
- move the typedefs and #defines above the type check macros
- add missing #include "qom/object.h" lines if necessary
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-9-ehabkost@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Message-Id: <20200831210740.126168-10-ehabkost@redhat.com>
Message-Id: <20200831210740.126168-11-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
In case the string doesn't fit into the buffer snprintf returns the size
it would need, so len can be larger than the buffer. Fix this by simply
using g_strdup_printf() instead of a static buffer.
Reported-by: Wenxiang Qian <leonwxqian@gmail.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Message-id: 20200701181801.27935-1-kraxel@redhat.com
The object_property_set_FOO() setters take property name and value in
an unusual order:
void object_property_set_FOO(Object *obj, FOO_TYPE value,
const char *name, Error **errp)
Having to pass value before name feels grating. Swap them.
Same for object_property_set(), object_property_get(), and
object_property_parse().
Convert callers with this Coccinelle script:
@@
identifier fun = {
object_property_get, object_property_parse, object_property_set_str,
object_property_set_link, object_property_set_bool,
object_property_set_int, object_property_set_uint, object_property_set,
object_property_set_qobject
};
expression obj, v, name, errp;
@@
- fun(obj, v, name, errp)
+ fun(obj, name, v, errp)
Chokes on hw/arm/musicpal.c's lcd_refresh() with the unhelpful error
message "no position information". Convert that one manually.
Fails to convert hw/arm/armsse.c, because Coccinelle gets confused by
ARMSSE being used both as typedef and function-like macro there.
Convert manually.
Fails to convert hw/rx/rx-gdbsim.c, because Coccinelle gets confused
by RXCPU being used both as typedef and function-like macro there.
Convert manually. The other files using RXCPU that way don't need
conversion.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200707160613.848843-27-armbru@redhat.com>
[Straightforwad conflict with commit 2336172d9b "audio: set default
value for pcspk.iobase property" resolved]
The only way object_property_add() can fail is when a property with
the same name already exists. Since our property names are all
hardcoded, failure is a programming error, and the appropriate way to
handle it is passing &error_abort.
Same for its variants, except for object_property_add_child(), which
additionally fails when the child already has a parent. Parentage is
also under program control, so this is a programming error, too.
We have a bit over 500 callers. Almost half of them pass
&error_abort, slightly fewer ignore errors, one test case handles
errors, and the remaining few callers pass them to their own callers.
The previous few commits demonstrated once again that ignoring
programming errors is a bad idea.
Of the few ones that pass on errors, several violate the Error API.
The Error ** argument must be NULL, &error_abort, &error_fatal, or a
pointer to a variable containing NULL. Passing an argument of the
latter kind twice without clearing it in between is wrong: if the
first call sets an error, it no longer points to NULL for the second
call. ich9_pm_add_properties(), sparc32_ledma_realize(),
sparc32_dma_realize(), xilinx_axidma_realize(), xilinx_enet_realize()
are wrong that way.
When the one appropriate choice of argument is &error_abort, letting
users pick the argument is a bad idea.
Drop parameter @errp and assert the preconditions instead.
There's one exception to "duplicate property name is a programming
error": the way object_property_add() implements the magic (and
undocumented) "automatic arrayification". Don't drop @errp there.
Instead, rename object_property_add() to object_property_try_add(),
and add the obvious wrapper object_property_add().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200505152926.18877-15-armbru@redhat.com>
[Two semantic rebase conflicts resolved]
Traditionally, the uint-specific property helpers only offer getters.
When adding object (or class) uint types, one must therefore use the
generic property helper if a setter is needed (and probably duplicate
some code writing their own getters/setters).
This enhances the uint-specific property helper APIs by adding a
bitwise-or'd 'flags' field and modifying all clients of that API to set
this paramater to OBJ_PROP_FLAG_READ. This maintains the current
behaviour whilst allowing others to also set OBJ_PROP_FLAG_WRITE (or use
the more convenient OBJ_PROP_FLAG_READWRITE) in the future (which will
automatically install a setter). Other flags may be added later.
Signed-off-by: Felipe Franciosi <felipe@nutanix.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit c388f408b5 added the possibility to list the display
backends using '-display help'. Since the 'none' backend is
is not implemented as a DisplayChangeListenerOps, it is not
registered to the dpys[] array with qemu_display_register(),
and is not listed in the help output.
This might be confusing, as we list it in the man page:
-display type
Select type of display to use. This option is a replacement for
the old style -sdl/-curses/... options. Valid values for type are
none
Do not display video output. The guest will still see an
emulated graphics card, but its output will not be displayed
to the QEMU user. This option differs from the -nographic
option in that it only affects what is done with video
output; -nographic also changes the destination of the serial
and parallel port data.
Fix by manually listing the special 'none' backend in the help.
Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20200120192947.31613-1-philmd@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
We already print availabled devices with "-device help", or available
backends with "-netdev help" or "-chardev help". Let's provide a way
for the users to query the available display backends, too.
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Message-id: 20200108144702.29969-1-thuth@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Don't attempt to remove /dev/fdset files.
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
The file opened for ppm_save() may be a /dev/fdset, in which case a
dup fd is added to the fdset. It should be removed by calling
qemu_close(), instead of the implicit close() on fclose().
I don't see a convenient way to solve that with stdio streams, so I
switched the code to QIOChannel which uses qemu_close().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
This will allow to pre-open the file before running the async finish
handler and avoid potential monitor fdset races.
(note: this is preliminary work for asynchronous screendump support)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Add a function to be called when a graphic update is done.
Declare the QXL renderer as async: render_update_cookie_num counts the
number of outstanding updates, and graphic_hw_update_done() is called
when it reaches none.
(note: this is preliminary work for asynchronous screendump support)
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Linux terminal behavior (coming from vt100 I think) is somewhat strange
when it comes to line wraps: When a character is printed to the last
char cell of a line the cursor does NOT jump to the next line but stays
where it is. The line feed happens when the next character is printed.
So the valid range for the cursor position is not 0 .. width-1 but
0 .. width, where x == width represents the state where the line is
full but the cursor didn't jump to the next line yet.
The code for the 'clear from start of line' control sequence (ESC[1K)
fails to handle this corner case correctly and may call
console_clear_xy() with x == width. That will incorrectly clear the
first char cell of the next line, or in case the cursor happens to be on
the last line overflow the cell buffer by one character (three bytes).
Add a check to the loop to fix that.
Didn't spot any other places with the same problem. But it's easy to
miss that corner case, so also allocate one extra cell as precaution, so
in case we have simliar issues lurking elsewhere it at least wouldn't be
a buffer overflow.
v2: squashed in additional checks suggested by Christophe de Dinechin.
Reported-by: Alexander Oleinik <alxndr@bu.edu>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Christophe de Dinechin <dinechin@redhat.com>
Message-id: 20190701075301.14165-1-kraxel@redhat.com
The qemu_create_display_surface_guestmem() function was added in
commit a77549b3ff but apparently never used. Remove it.
(The API of this function is in any case awkward as a generic
function: it assumes that a physical address uniquely identifies
a piece of memory in the system, which is mostly but not
always true.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20181122170309.4856-1-peter.maydell@linaro.org
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
A link property can be set during creation, with
object_property_add_link() and later with object_property_set_link().
add_link() doesn't add a reference to the target object, while
set_link() does.
Furthemore, OBJ_PROP_LINK_UNREF_ON_RELEASE flags, set during add_link,
says whether a reference must be released when the property is destroyed.
This can lead to leaks if the property was later set_link(), as the
added reference is never released.
Instead, rename OBJ_PROP_LINK_UNREF_ON_RELEASE to OBJ_PROP_LINK_STRONG
and use that has an indication on how the link handle reference
management in set_link().
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 20180531195119.22021-3-marcandre.lureau@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
After f771c5440e it is possible to select device and
head which to take screendump from. And even though we check if
provided head number falls within range, it may still happen that
the console has no surface yet leading to SIGSEGV:
qemu.git $ ./x86_64-softmmu/qemu-system-x86_64 \
-qmp stdio \
-device virtio-vga,id=video0,max_outputs=4
{"execute":"qmp_capabilities"}
{"execute":"screendump", "arguments":{"filename":"/tmp/screen.ppm", "device":"video0", "head":1}}
Segmentation fault
#0 0x00005628249dda88 in ppm_save (filename=0x56282826cbc0 "/tmp/screen.ppm", ds=0x0, errp=0x7fff52a6fae0) at ui/console.c:304
#1 0x00005628249ddd9b in qmp_screendump (filename=0x56282826cbc0 "/tmp/screen.ppm", has_device=true, device=0x5628276902d0 "video0", has_head=true, head=1, errp=0x7fff52a6fae0) at ui/console.c:375
#2 0x00005628247740df in qmp_marshal_screendump (args=0x562828265e00, ret=0x7fff52a6fb68, errp=0x7fff52a6fb60) at qapi/qapi-commands-ui.c:110
Here, @ds from frame #0 (or @surface from frame #1) is
dereferenced at the very beginning of ppm_save(). And because
it's NULL crash happens.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-id: cb05bb1909daa6ba62145c0194aafa05a14ed3d1.1526569138.git.mprivozn@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
dpy_gfx_update_full is used to do the whole display surface update.
This function is proposed by Gerd Hoffmann.
Signed-off-by: Tina Zhang <tina.zhang@intel.com>
Message-id: 1524820266-27079-2-git-send-email-tina.zhang@intel.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
This patch allows to unbind devices from QemuConsoles, using the new
graphic_console_close() function. The QemuConsole will show a static
display then, saying the device was unplugged. When re-plugging a
display later on the QemuConsole will be reused.
Eventually we will allocate and release QemuConsoles dynamically at some
point in the future, that'll need more infrastructure though to notify
user interfaces (gtk, sdl, spice, ...) about QemuConsoles coming and
going.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
QEMU's screendump command can only take dumps from the primary display.
When using multiple VGA cards, there is no way to get a dump from a
secondary card or other display heads yet. So let's add a 'device' and
a 'head' parameter to the HMP and QMP commands to be able to specify
alternative devices and heads with the screendump command, too.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1520267868-31778-1-git-send-email-thuth@redhat.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Secondary displays in multihead setups are allowed to have a NULL
DisplaySurface. Typically user interfaces handle this by hiding the
window which shows the display in question.
This isn't an option for vnc though because it simply hasn't a concept
of windows or outputs. So handle the situation by showing a placeholder
DisplaySurface instead. Also check in console_select whenever a surface
is preset in the first place before requesting an update.
This fixes a segfault which can be triggered by switching to an unused
display (via vtrl-alt-<nr>) in a multihead setup, for example using
-device virtio-vga,max_outputs=2.
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Message-id: 20180308161803.6152-1-kraxel@redhat.com