I investigated a bug in module-loopback reported[1] by Fr?d?ric
Dalleau last year. The instructions for reproduction were as follows:
1. Have one sound card (index 0) loaded with one sink (index 0) and
one source (index 1), plus the monitor source (index 0)
2. pactl load-module module-loopback sink=0 source=0
3. pactl set-card-profile 0 off
These steps caused reliable crashing, and after fixing the first
issue, two more cropped up. The first three patches fix these three
issues. When I investigated in more detail the exact conditions that
caused the first crash, I found out that module-alsa-card was doing
something that it shouldn't do: it was moving streams. The last patch
fixes that.
Removing the stream moving from module-alsa-card causes a change in
behavior that perhaps isn't acceptable: if a sink is removed due to
a profile change and a new sink is created, the streams connected to
the old sink aren't necessarily moved to the new sink. If this is
unacceptable, the old policy should be reimplemented somewhere else,
perhaps in module-rescue-streams.
[1] http://thread.gmane.org/gmane.comp.audio.pulseaudio.general/13408
Tanu Kaskinen (4):
loopback: Fix segfault in may_move_to() callbacks
filter-apply: Fix segfault with moving streams
loopback: Flush asyncmsgq from the right context
alsa: Don't move streams when changing profiles
src/modules/alsa/module-alsa-card.c | 19 ------------
src/modules/module-filter-apply.c | 10 +++++--
src/modules/module-loopback.c | 55 ++++++++++++++++++++++++-----------
3 files changed, 45 insertions(+), 39 deletions(-)
--
1.7.10.4
