Currently, the Kbuild core manipulates header search paths in a crazy
way [1].
To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.
Having whitespaces after -I does not matter since commit 48f6e3cf5b
("kbuild: do not drop -I without parameter").
[1]: https://patchwork.kernel.org/patch/9632347/
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Sakari Ailus <sakari.ailus@linux.intel.com>
The ctrl_check_input() function is called from pvr2_ctrl_range_check().
It's supposed to validate user supplied input and return true or false
depending on whether the input is valid or not. The problem is that
negative shifts or shifts greater than 31 are undefined in C. In
practice with GCC they result in shift wrapping so this function returns
true for some inputs which are not valid and this could result in a
buffer overflow:
drivers/media/usb/pvrusb2/pvrusb2-ctrl.c:205 pvr2_ctrl_get_valname()
warn: uncapped user index 'names[val]'
The cptr->hdw->input_allowed_mask mask is configured in pvr2_hdw_create()
and the highest valid bit is BIT(4).
Fixes: 7fb20fa38c ("V4L/DVB (7299): pvrusb2: Improve logic which handles input choice availability")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If the application was streaming from both videoX and vbiX, and streaming
from videoX was stopped, then the vbi streaming also stopped.
The cause being that stop_streaming for video stopped the subdevs as well,
instead of only doing that if dev->streaming_users reached 0.
au0828_stop_vbi_streaming was also wrong since it didn't stop the subdevs
at all when dev->streaming_users reached 0.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Tested-by: Shuah Khan <shuah@kernel.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Enable and disable source interfaces aren't consistent in enforcing
how video and audio share the tuner resource.
Fix these issues to enforce the following rules and allow
sharing between audio and video applications.
- When DVB is streaming, audio/video/vbi/s-video/composite
should find the resource busy. DVB holds the tuner in
exclusive mode.
- When video/VBI is streaming, audio can share the tuner and vice versa.
- v4l2 allows multiple applications to open video device.
- Video applications call enable source multiple times during their
run-time. Resource should stay locked until the last application
releases it.
- A shared resource should stay in shared state and locked when it is
in use by audio and video. More than one video application is allowed
to use the tuner as long as video streaming protocol allows such usage.
Resource is released when the last video/audio application releases it.
- S-Video and Composite hold the resource in exclusive mode.
Signed-off-by: Shuah Khan <shuah@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Media Device Allocator API to allows multiple drivers share a media device.
This API solves a very common use-case for media devices where one physical
device (an USB stick) provides both audio and video. When such media device
exposes a standard USB Audio class, a proprietary Video class, two or more
independent drivers will share a single physical USB bridge. In such cases,
it is necessary to coordinate access to the shared resource.
Using this API, drivers can allocate a media device with the shared struct
device as the key. Once the media device is allocated by a driver, other
drivers can get a reference to it. The media device is released when all
the references are released.
Change au0828 to use Media Device Allocator API to allocate media device
with the parent usb struct device as the key, so it can be shared with the
snd_usb_audio driver.
Signed-off-by: Shuah Khan <shuah@kernel.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The strncpy() function is being deprecated upstream. Replace
it by the safer strscpy().
While here, replace a few occurences of strlcpy() that were
recently added to also use strscpy().
Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In case usb_alloc_coherent fails, the fix returns -ENOMEM to
avoid a potential NULL pointer dereference.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In order to prevent ISOC URBs from being infinitely resubmitted,
the driver's USB disconnect handler must kill all the in-flight URBs.
While here, change the URB packet status message to a debug level,
to avoid spamming the console too much.
This commit fixes a lockup caused by an interrupt storm coming
from the URB completion handler.
Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The way the code works, compression will be a valid value (less or equal to 3)
on both set_video_mode_foo() calls at the beginning of the while() loop.
So, the value for pChoose can't be NULL.
Solves those smatch warnings:
drivers/media/usb/pwc/pwc-ctrl.c: drivers/media/usb/pwc/pwc-ctrl.c:252 set_video_mode_Timon() warn: variable dereferenced before check 'pChoose' (see line 248)
drivers/media/usb/pwc/pwc-ctrl.c: drivers/media/usb/pwc/pwc-ctrl.c:302 set_video_mode_Kiara() warn: variable dereferenced before check 'pChoose' (see line 298)
and simplifies the code a little bit.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Checkpatch wants to use 'help' instead of '---help---':
WARNING: prefer 'help' over '---help---' for new help texts
Let's change it globally at the media subsystem, as otherwise people
would keep using the old way.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Don't populate the array addr_list on the stack but instead make it
static. Makes the object code smaller by 20 bytes
Before:
text data bss dec hex filename^M
16929 3626 384 20939 51cb ../usb/em28xx/em28xx-input.o
After:
text data bss dec hex filename^M
16829 3706 384 20919 51b7 ../usb/em28xx/em28xx-input.o
(gcc version 8.3.0, aarch64)
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This patch add support for Avermedia TD310 usb stick.
Signed-off-by: Jose Alberto Reguero <jose.alberto.reguero@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
i2c bus is already needed when the frontend is probed, so init it already
in it930x_frontend_attach. That prevents errors like:
si2168: probe of 6-0067 failed with error -5
Signed-off-by: Andreas Kemnade <andreas@kemnade.info>
Signed-off-by: Jose Alberto Reguero <jose.alberto.reguero@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Commit 14f4eaedda ("media: dvbsky: fix driver unregister logic") fixed
a use-after-free by removing the reference to the frontend after deleting
the backing i2c device.
This has the unfortunate side effect the frontend device is never freed
in the dvb core leaving a dangling device, leading to errors when the
dvb core tries to register the frontend after e.g. a replug as reported
here: https://www.spinics.net/lists/linux-media/msg138181.html
media: dvbsky: issues with DVBSky T680CI
===
[ 561.119145] sp2 8-0040: CIMaX SP2 successfully attached
[ 561.119161] usb 2-3: DVB: registering adapter 0 frontend 0 (Silicon Labs
Si2168)...
[ 561.119174] sysfs: cannot create duplicate filename '/class/dvb/
dvb0.frontend0'
===
The use after free happened as dvb_usbv2_disconnect calls in this order:
- dvb_usb_device::props->exit(...)
- dvb_usbv2_adapter_frontend_exit(...)
+ if (fe) dvb_unregister_frontend(fe)
+ dvb_usb_device::props->frontend_detach(...)
Moving the release of the i2c device from exit() to frontend_detach()
avoids the dangling pointer access and allows the core to unregister
the frontend.
This was originally reported for a DVBSky T680CI, but it also affects
the MyGica T230C. As all supported devices structure the registration/
unregistration identically, apply the change for all device types.
Signed-off-by: Stefan Brüns <stefan.bruens@rwth-aachen.de>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
When streaming is stopped all URBs are killed, but in fill_frame and in
bulk_irq this results in an attempt to resubmit the killed URB. That is
not what you want and causes spurious kernel messages.
So check if streaming has stopped before resubmitting.
Also check against gspca_dev->streaming rather than vb2_start_streaming_called()
since vb2_start_streaming_called() will return true when in stop_streaming,
but gspca_dev->streaming is set to false when stop_streaming is called.
Fixes: 6992effe53 ("gspca: Kill all URBs before releasing any of them")
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
clang-8 warns about one function here when KASAN is enabled, even
without the 'asan-stack' option:
drivers/media/usb/go7007/go7007-fw.c:1551:5: warning: stack frame size of 2656 bytes in function
I have reported this issue in the llvm bugzilla, but to make
it work with the clang-8 release, a small annotation is still
needed.
Link: https://bugs.llvm.org/show_bug.cgi?id=38809
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil-cisco@xs4all.nl: fix checkpatch warning]
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Those typos were left over from codespell check, on
my first pass or belong to code added after the time I
ran it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Use codespell to fix lots of typos over frontends.
Manually verified to avoid false-positives.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The uvc driver uses this function to fill in bus_info for VIDIOC_QUERYCAP,
so use the same function when filling in the bus_info for the media device.
The current implementation only fills in part of the info. E.g. if the full
bus_info is usb-0000:01:00.0-1.4.2, then the media bus_info only has 1.4.2.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
drivers/media/usb/hdpvr/hdpvr-i2c.c: drivers/media/usb/hdpvr/hdpvr-i2c.c:78 hdpvr_i2c_read() warn: 'dev->i2c_buf' 4216624615462223872 can't fit into 127 '*data'
dev->i2c_buf is a char array, so you can just use dev->i2c_buf to get the
start address, no need to do &dev->i2c_buf, even though it is the same
address in C. It only confuses smatch.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Just like vb2 does, use u64 internally to store the timestamps
of the buffers. Only convert to timeval when interfacing with
userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Acked-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The UVC video driver converts the timestamp from hardware specific unit
to one known by the kernel at the time when the buffer is dequeued. This
is fine in general, but the streamoff operation consists of the
following steps (among other things):
1. uvc_video_clock_cleanup --- the hardware clock sample array is
released and the pointer to the array is set to NULL,
2. buffers in active state are returned to the user and
3. buf_finish callback is called on buffers that are prepared.
buf_finish includes calling uvc_video_clock_update that accesses the
hardware clock sample array.
The above is serialised by a queue specific mutex. Address the problem
by skipping the clock conversion if the hardware clock sample array is
already released.
Fixes: 9c0863b1cc ("[media] vb2: call buf_finish from __queue_cancel")
Reported-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Tested-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
When initially testing the Camera Terminal Descriptor wTerminalType
field (buffer[4]), no mask is used. Later in the function, the MSB is
overloaded to store the descriptor subtype, and so a mask of 0x7fff
is used to check the type.
If a descriptor is specially crafted to set this overloaded bit in the
original wTerminalType field, the initial type check will fail (falling
through, without adjusting the buffer size), but the later type checks
will pass, assuming the buffer has been made suitably large, causing an
overflow.
Avoid this problem by checking for the MSB in the wTerminalType field.
If the bit is set, assume the descriptor is bad, and abort parsing it.
Originally reported here:
https://groups.google.com/forum/#!topic/syzkaller/Ot1fOE6v1d8
A similar (non-compiling) patch was provided at that time.
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Alistair Strachan <astrachan@google.com>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The COM3 register at address 0x0c already defaults to 0x10, the two bits
COM3[7:6] are set according to V4L2 controls by sethvflip later.
There is no need to set it multiple times during bridge initialization.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
This register is later overwritten by set_frame_rate anyway.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The video format, payload size, and frame size setup is video format
and frame size specific. Those registers are overwritten during
bridge_start anyway.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Add support to pass through the sensor's native SGBRG8 bayer pattern,
allowing to cut the required USB bandwidth in half.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In preparation for adding SGBRG8 as a second video format besides YUYV,
move video format specific register settings from the bridge_init array
into the bridge_start arrays.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If a driver supports multiple pixel formats with the same frame size,
TRY_FMT will currently always return the first pixel format.
Fix this by adding pixelformat support to wxh_to_nearest_mode().
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
If a driver supports multiple pixel formats with the same frame size,
ENUM_FRAMEINTERVALS will currently only work for the first pixel format.
Fix this by adding pixelformat support to wxh_to_mode().
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
For short waits, usleep_range should be used instead of msleep,
see Documentation/timers/timers-howto.txt.
Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In mt9m111_probe, m5602_write_bridge can timeout and return a negative
error value. The fix checks for this error and passes it upstream.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
In po1030_probe(), m5602_write_bridge() can timeout and return an error
value. The fix checks for the return value and propagates upstream
consistent with other usb drivers.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The fix checks if goto_low_power() fails, and if so, issues an error
message.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
do_command() may fail. The fix adds the missed return value of
do_command(). If it fails, returns its error code.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Control events can leak kernel memory since they do not fully zero the
event. The same code is present in both v4l2-ctrls.c and uvc_ctrl.c, so
fix both.
It appears that all other event code is properly zeroing the structure,
it's these two places.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Reported-by: syzbot+4f021cf3697781dbd9fb@syzkaller.appspotmail.com
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
DMA cocherency slows the transfer down on systems without hardware
coherent DMA.
Instead we use noncocherent DMA memory and explicit sync at data receive
handler.
Based on previous commit the following performance benchmarks have been
carried out. Average memcpy() data transfer rate (rate) and handler
completion time (time) have been measured when running video stream at
640x480 resolution at 10fps.
x86_64 based system (Intel Core i5-3470). This platform has hardware
coherent DMA support and proposed change doesn't make big difference here.
* kmalloc: rate = (2.0 +- 0.4) GBps
time = (5.0 +- 3.0) usec
* usb_alloc_coherent: rate = (3.4 +- 1.2) GBps
time = (3.5 +- 3.0) usec
We see that the measurements agree within error ranges in this case.
So theoretically predicted performance downgrade cannot be reliably
measured here.
armv7l based system (TI AM335x BeagleBone Black @ 300MHz). This platform
has no hardware coherent DMA support. DMA coherence is implemented via
disabled page caching that slows down memcpy() due to memory controller
behaviour.
* kmalloc: rate = ( 94 +- 4) MBps
time = (101 +- 4) usec
* usb_alloc_coherent: rate = (28.1 +- 0.1) MBps
time = (341 +- 2) usec
Note, that quantative difference leads (this commit leads to 3.3 times
acceleration) to qualitative behavior change in this case. As it was
stated before, the video stream cannot be successfully received at AM335x
platforms with MUSB based USB host controller due to performance issues
[1].
[1] https://www.spinics.net/lists/linux-usb/msg165735.html
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
There were reports that PWC-based webcams don't work at some
embedded ARM platforms. [1] Isochronous transfer handler seems to
work too long leading to the issues in MUSB USB host subsystem.
Also note, that urb->giveback() handlers are still called with
disabled interrupts. In order to be able to measure performance of
PWC driver, traces are introduced in URB handler section.
[1] https://www.spinics.net/lists/linux-usb/msg165735.html
Signed-off-by: Matwey V. Kornilov <matwey@sai.msu.ru>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
kmemdup has implemented the function that kmalloc() + memcpy().
We prefer to kmemdup rather than code opened implementation.
This issue was detected with the help of coccinelle.
Signed-off-by: Wen Yang <wen.yang99@zte.com.cn>
CC: Tomoki Sekiyama <tomoki.sekiyama@gmail.com>
CC: linux-kernel@vger.kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
There is a spelling mistake in a pvr2_trace trace message, fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Interrupt is always present throughout life time of driver and
there is no dma element move this buffer to private area of driver.
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
The interrupt urb is killed but never freed add the function
Signed-off-by: Malcolm Priestley <tvboxspy@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Masahiro Yamada
Dan Carpenter
Hans Verkuil
Shuah Khan
Mauro Carvalho Chehab
Kangjie Lu
Ezequiel Garcia
Colin Ian King
Jose Alberto Reguero
Andreas Kemnade
Stefan Brüns
Hans Verkuil
Arnd Bergmann
YueHaibing
Sakari Ailus
Alistair Strachan
Philipp Zabel
Aditya Pakki
Matwey V. Kornilov
Wen Yang
Malcolm Priestley