It's just happened to me once again, but this time I was running it from a terminal. The last (and I think only relevant) message was:
E: thread-posix.c: Assertion 'pthread_setspecific(t->key, userdata) == 0' failed at pulsecore/thread-posix.c:194, function pa_tls_set(). Aborting.
I had recently seen a blog post suggesting pulseaudio might sometime be responsible for uninterruptible processes. Well, it seems to me like this message confirms it (the assertion is thrown from pulsecore).
It's just happened to me once again, but this time I was running it from a terminal. The last (and I think only relevant) message was:
E: thread-posix.c: Assertion 'pthread_ setspecific( t->key, userdata) == 0' failed at pulsecore/ thread- posix.c: 194, function pa_tls_set(). Aborting.
I had recently seen a blog post suggesting pulseaudio might sometime be responsible for uninterruptible processes. Well, it seems to me like this message confirms it (the assertion is thrown from pulsecore).
HTH