Board hangs with 'dtoverlay=vc4-kms-v3d' while writing to /dev/fb0
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux-raspi2 (Ubuntu) |
New
|
Undecided
|
Unassigned | ||
Xenial |
Fix Released
|
Undecided
|
Unassigned |
Bug Description
Impact:
There is a kernel hang in 4.4.y if the vc4 driver is enabled, and another program opens /dev/fb0 to display an image.
Fix:
Apply the attached patch and recompile the kernel.
How to test:
Enable the gpu hardware acceleration by loading the vc4 overlay:
config.txt:
...
dtoverlay=
...
reboot and check that vc4 was activated:
$ dmesg | grep vc4
...
[ 15.274385] vc4-drm soc:gpu: bound 3f902000.hdmi (ops vc4_hdmi_ops [vc4])
[ 15.274660] vc4_dsi 3f700000.dsi: DSI not set up by firmware.
[ 15.274753] vc4-drm soc:gpu: bound 3f700000.dsi (ops vc4_dsi_ops [vc4])
[ 15.274873] vc4-drm soc:gpu: bound 3f400000.hvs (ops vc4_hvs_ops [vc4])
[ 15.275178] vc4-drm soc:gpu: bound 3f206000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 15.275407] vc4-drm soc:gpu: bound 3f207000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 15.275643] vc4-drm soc:gpu: bound 3f807000.pixelvalve (ops vc4_crtc_ops [vc4])
[ 15.275818] vc4-drm soc:gpu: bound 3fc00000.v3d (ops vc4_v3d_ops [vc4])
[ 15.403354] vc4-drm soc:gpu: fb0: frame buffer device
...
then download and compile psplash:
$ git clone git://git.
$ cd psplash
$ autoreconf --install
$ ./configure
$ make
$ sudo ./psplash
here the board should hang, pull the plug to get it back.
Now install the patched kernel, and execute psplash again - the board will be fine, and a bitmap will be displayed on hdmi, ctrl+c to exit psplash.
--
CVE References
tags: | added: patch |
Changed in linux-raspi2 (Ubuntu Xenial): | |
status: | New → Fix Committed |
tags: |
added: verification-done-xenial removed: verification-needed-xenial |
This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification- needed- xenial' to 'verification- done-xenial' . If the problem still exists, change the tag 'verification- needed- xenial' to 'verification- failed- xenial' .
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.
See https:/ /wiki.ubuntu. com/Testing/ EnableProposed for documentation how to enable and use -proposed. Thank you!