Webcam not working. /dev/video0 (No such file or directory)

[Pedro Coca]

Webcam demo from the store not working on latest snappy image (not a hw-assign permission issue)

snappy info & list
==============

(amd64)ubuntu@localhost:~$ snappy info
release: ubuntu-core/15.04/stable
architecture: amd64
frameworks: docker.canonical, webdm.canonical
apps: crossbar.crossbar, webcam-demo.canonical
(amd64)ubuntu@localhost:~$ snappy list
Name Date Version Developer
ubuntu-core 2015-11-13 10 ubuntu
crossbar 2015-12-01 0.10.4 crossbar
docker 2015-12-01 1.6.2.005 canonical
webcam-demo 2015-12-01 1.0.2 canonical
webdm 2015-11-13 0.9.4 canonical
generic-amd64 2015-11-13 1.4 canonical

hw-assign
========
(amd64)ubuntu@localhost:~$ sudo snappy hw-assign webcam-demo.canonical /dev/video0
'webcam-demo.canonical' previously allowed access to '/dev/video0'. Skipping

 systemctl status
==============

(amd64)ubuntu@localhost:~$ systemctl status webcam-demo_webcam-demo_1.0.2.service
● webcam-demo_webcam-demo_1.0.2.service - webcam service that provides a webserver and takes snapshots every 10 seconds
   Loaded: loaded (/etc/systemd/system/webcam-demo_webcam-demo_1.0.2.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2015-12-01 17:05:18 UTC; 24min ago
 Main PID: 879 (webcam-webui)
   CGroup: /system.slice/webcam-demo_webcam-demo_1.0.2.service
           ├─ 879 /bin/sh /apps/webcam-demo.canonical/1.0.2/bin/webcam-webui
           ├─ 884 golang-static-http
           └─2945 sleep 10

/dev/video0 cannot be found:

Syslog:
======

Dec 1 17:10:20 localhost ubuntu-core-launcher[879]: #033[0m#033[31mstat: No such file or directory
Dec 1 17:10:21 localhost kernel: [ 393.277710] usb 1-2: USB disconnect, device number 3
Dec 1 17:10:21 localhost systemd-udevd[379]: error opening USB device 'descriptors' file
Dec 1 17:10:23 localhost kernel: [ 394.568843] usb 1-2: new high-speed USB device number 7 using xhci_hcd
Dec 1 17:10:23 localhost kernel: [ 394.793297] usb 1-2: New USB device found, idVendor=041e, idProduct=4097
Dec 1 17:10:23 localhost kernel: [ 394.793320] usb 1-2: New USB device strings: Mfr=3, Product=1, SerialNumber=2
Dec 1 17:10:23 localhost kernel: [ 394.793335] usb 1-2: Product: Live! Cam Chat HD VF0790
Dec 1 17:10:23 localhost kernel: [ 394.793349] usb 1-2: Manufacturer: Creative Technology Ltd.
Dec 1 17:10:23 localhost kernel: [ 394.793362] usb 1-2: SerialNumber: 2015042002502
Dec 1 17:10:23 localhost kernel: [ 394.812901] hid-generic 0003:041E:4097.0004: hiddev0,hidraw0: USB HID v1.11 Device [Creative Technology Ltd. Live! Cam Chat HD VF0790] on usb-0000:00:14.0-2/input4
Dec 1 17:10:30 localhost ubuntu-core-launcher[879]: #033[0m#033[1m--- Opening /dev/video0...
Dec 1 17:10:30 localhost ubuntu-core-launcher[879]: #033[0m#033[31mstat: No such file or directory

[Alexander Sack (asac)]

Hi,

is any dev/videoX device created for you?

What is the last image that works with that webcam?

[Pedro Coca (pcoca)]

On Tue, Dec 1, 2015 at 7:23 PM, Alexander Sack <email address hidden> wrote:
> Hi,
>
> is any dev/videoX device created for you?

No

> What is the last image that works with that webcam?

In V9 (2015-10-23) works fine.

> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1521710
>
> Title:
> Webcam not working. /dev/video0 (No such file or directory)
>
> Status in Snappy:
> New
>
> Bug description:
>
> Webcam demo from the store not working on latest snappy image (not a hw-assign permission issue)
>
>
> snappy info & list
> ==============
>
> (amd64)ubuntu@localhost:~$ snappy info
> release: ubuntu-core/15.04/stable
> architecture: amd64
> frameworks: docker.canonical, webdm.canonical
> apps: crossbar.crossbar, webcam-demo.canonical
> (amd64)ubuntu@localhost:~$ snappy list
> Name Date Version Developer
> ubuntu-core 2015-11-13 10 ubuntu
> crossbar 2015-12-01 0.10.4 crossbar
> docker 2015-12-01 1.6.2.005 canonical
> webcam-demo 2015-12-01 1.0.2 canonical
> webdm 2015-11-13 0.9.4 canonical
> generic-amd64 2015-11-13 1.4 canonical
>
> hw-assign
> ========
> (amd64)ubuntu@localhost:~$ sudo snappy hw-assign webcam-demo.canonical /dev/video0
> 'webcam-demo.canonical' previously allowed access to '/dev/video0'. Skipping
>
>
> systemctl status
> ==============
>
> (amd64)ubuntu@localhost:~$ systemctl status webcam-demo_webcam-demo_1.0.2.service
> ● webcam-demo_webcam-demo_1.0.2.service - webcam service that provides a webserver and takes snapshots every 10 seconds
> Loaded: loaded (/etc/systemd/system/webcam-demo_webcam-demo_1.0.2.service; enabled; vendor preset: enabled)
> Active: active (running) since Tue 2015-12-01 17:05:18 UTC; 24min ago
> Main PID: 879 (webcam-webui)
> CGroup: /system.slice/webcam-demo_webcam-demo_1.0.2.service
> ├─ 879 /bin/sh /apps/webcam-demo.canonical/1.0.2/bin/webcam-webui
> ├─ 884 golang-static-http
> └─2945 sleep 10
>
> /dev/video0 cannot be found:
>
> Syslog:
> ======
>
> Dec 1 17:10:20 localhost ubuntu-core-launcher[879]: #033[0m#033[31mstat: No such file or directory
> Dec 1 17:10:21 localhost kernel: [ 393.277710] usb 1-2: USB disconnect, device number 3
> Dec 1 17:10:21 localhost systemd-udevd[379]: error opening USB device 'descriptors' file
> Dec 1 17:10:23 localhost kernel: [ 394.568843] usb 1-2: new high-speed USB device number 7 using xhci_hcd
> Dec 1 17:10:23 localhost kernel: [ 394.793297] usb 1-2: New USB device found, idVendor=041e, idProduct=4097
> Dec 1 17:10:23 localhost kernel: [ 394.793320] usb 1-2: New USB device strings: Mfr=3, Product=1, SerialNumber=2
> Dec 1 17:10:23 localhost kernel: [ 394.793335] usb 1-2: Product: Live! Cam Chat HD VF0790
> Dec 1 17:10:23 localhost kernel: [ 394.793349] usb 1-2: Manufacturer: Creative Technology Ltd.
> Dec 1 17:10:23 localhost kernel: [ 394.793362] usb 1-2: SerialNumber: 2015042002502
> Dec 1 17:10:23 localhost kernel: [ 394.812901] hid-generic 0003:041E:4097.0004: hiddev0,hidraw0...

[Pedro Coca (pcoca)]

No /dev/videoX I'm afraid.

 In V9 (2015-10-23) works fine.

[Oliver Grawert (ogra)]

do you have the full syslog you could attach ?

[Pedro Coca (pcoca)]

The system has been updated automatically to version 10 and the webcam-demo has not stop working, so the issue can be observed with a fresh installation of snappy V.10.

[Pedro Coca (pcoca)]

syslog file attached.

[Oliver Grawert (ogra)]

weird, your log looks like it is capturing images:

Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[1m--- Opening /dev/video0...
Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[0mTrying source module v4l2...
Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[0m/dev/video0 opened.
Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[0mNo input was specified, using the first.
Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[0mAdjusting resolution from 384x288 to 320x240.
Dec 1 19:12:03 localhost ubuntu-core-launcher[1931]: #033[0m#033[1m--- Capturing frame...

[Pedro Coca (pcoca)]

Yes, because that's the syslog of the snappy V9 version install updated to V10.

The syslog of a snappy V10 direct installation cannot be attached as we reflashed it.
We can reflash the V10 image tomorrow to reproduce the bug and attached the fresh V10 install syslog.

[Michael Vogt (mvo)]

I tried to reproduce this issue this moring. I used a 15.04 stable v10 image (freshly flashed) and followed the exact steps from this bugreport, i.e.
$ sudo snappy install webcam-demo.canonical
$ sudo snappy hw-assign webcam-demo.canonical /dev/video0

I got the expected message:
'webcam-demo.canonical' is now allowed to access /dev/video0

and the webcam demo works just fine for me. I tried this on real hardware two times, once a fresh r10 and once on a r6->r10 upgraded system (but did all the install/assign on the r10 version).

The message you got earlier:
   'webcam-demo.canonical' previously allowed access to '/dev/video0'. Skipping
indicates that the system might be in a different state than a fresh install. Were there installs/removals or hw-assign/unassign happening before? If so there may well be a bug but any hints how to reproduce that bug would be very helpful (like a bash history with the commands that were run before the error happened).

[Pedro Coca (pcoca)]

I've reproduced the issue this morning again with a fresh install of snappy Ubuntu Core V10.

Attached logs (syslog, dmesg, bash history, etc) on tar.gz file.

[Oliver Grawert (ogra)]

comparing the syslogs it seems that the uvcvideo driver does not get loaded ... can you attach the output of lsmod with the camera plugged in ?

[Pedro Coca (pcoca)]

lsmod output with the camera plugged in:

(amd64)ubuntu@localhost:~$ lsmod
Module Size Used by
nls_iso8859_1 16384 1
autofs4 40960 2
mmc_block 36864 5
hid_generic 16384 0
usbhid 53248 0
hid 110592 2 hid_generic,usbhid
psmouse 118784 0
r8169 81920 0
mii 16384 1 r8169
ahci 36864 0
libahci 32768 1 ahci
sdhci_acpi 16384 0
sdhci 45056 1 sdhci_acpi

[Oliver Grawert (ogra)]

does /dev/video0 show up if you manually do "sudo modprobe uvcvideo" ?

[Pedro Coca (pcoca)]

It does show up:

(amd64)ubuntu@localhost:~$ ls /dev/v*
/dev/vcs /dev/vcs3 /dev/vcs6 /dev/vcsa2 /dev/vcsa5 /dev/vhci
/dev/vcs1 /dev/vcs4 /dev/vcsa /dev/vcsa3 /dev/vcsa6 /dev/vhost-net
/dev/vcs2 /dev/vcs5 /dev/vcsa1 /dev/vcsa4 /dev/vga_arbiter

/dev/vfio:
vfio
(amd64)ubuntu@localhost:~$ sudo modprobe uvcvideo
modprobe: ERROR: ../libkmod/libkmod-index.c:822 index_mm_open() magic check fail: c03b3998 instead of b007f457
(amd64)ubuntu@localhost:~$ ls /dev/v*
/dev/vcs /dev/vcs3 /dev/vcs6 /dev/vcsa2 /dev/vcsa5 /dev/vhci
/dev/vcs1 /dev/vcs4 /dev/vcsa /dev/vcsa3 /dev/vcsa6 /dev/vhost-net
/dev/vcs2 /dev/vcs5 /dev/vcsa1 /dev/vcsa4 /dev/vga_arbiter /dev/video0

/dev/v4l:
by-id by-path

/dev/vfio:
vfio
(amd64)ubuntu@localhost:~$

[Pedro Coca (pcoca)]

After /dev/video0 shows up and using hw-assign primitive, the demo works.

[Shuduo Sang (sangshuduo)]

I use a Logitech C170 webcam but failed to decode the its data. But the data can be decoded by gstreamer command line "gst-launch-1.0 v4l2src device=/dev/video1 ! xvimagesink" on classic ubuntu. I suggest we continue to improve webcam demo to support more devices.

[Launchpad Janitor (janitor)]

[Expired for Snappy because there has been no activity for 60 days.]