If you have previously flashed any version of a Sony-Open-Devices-based ROM
from before December 17th 2018, your
dsp partition might have wrong
SELinux labels and you might thus have problems with audio.
su # It might be either /system/vendor/dsp or /vendor/dsp depending on your device # Just try both until one succeeds mount -o remount,rw /system/vendor/dsp chcon -R u:object_r:adsprpcd_file:s0 /dsp
Reboot, et voilà - you should have proper audio again.
If you only want to fix your audio problem, you can stop reading now.
Sony devices have a
dsp partition that holds firmware files and libraries
needed for the Qualcomm “Hexagon” DSP - Digital Signal Processor.
The partition is shippped with the SELinux file label
u:object_r:adsprpcd_file:s0 by default, and stock firmware uses this label
as well when flashed via
When stellirin rewrote the SODP sepolicy in late 2017, they
chose to use
qdsp_file instead of
A few lines of code were added in
init.$device.rc - which gets
run under the label
vendor_init - to re-mount the dsp partition and update it
to use the
Because re-labeling these files as
vendor_init is a
neverallow in Pie, we noticed that we should rather be
re-using the stock file labels, i.e.
The relabeling bit(
restorecon_recursive) was removed
from its new location in
init.common.rc and the “new” old label
As stated in the “short version”, fixing the problem is easy: Run
chcon or run
Emma - Emma can now flash single partitions, which is great.
A small inconsistency can cause a whole lot of trouble. Who could have predicted
back in 2017 that Google would tighten the security around re-labeling files?
The transition is going to be a bit painful, but in the end, re-using
adsprpcd_file is the better solution.