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Re: crash with latest audio changes
On Fri, 16 Dec 2016, Christos Zoulas wrote:
audio_get_port+0x7e is this line:
return sc->hw_if->get_port(sc->hw_hdl, mc);
I don't see how we can get there with sc->hw_if being NULL..
Add some printfs to see what's NULL...
I've been staring at this in sys/dev/audio.c and trying to learn from this
situation. I have some ignorant (because I'm not a kernel coder and only
have about 30k lines of C under my belt) questions:
If nobody cares, that's cool. It was just an exercise for me.
* Why not check the input values in au_get_lr_value() ? It appears to
blindly use the first two input structures without checking if they are
null. So does au_get_gain() and others. Does that kind of thing slow the
driver down too much or is the input checked elsewhere before being
* Dunno where get_port() comes from but shouldn't it also check it's first
argument (a struct) for NULL?
* In audio_mixer_capture(), why do this:
That doesn't appear to do anything other than call a function that reads
a value. Does it actually assign the value somehow? Is one of those some
kind of queue that get_port alters after reading ?
* audio_mixer_restore() also blindly uses a audio_softc struct, but is it
really blind? Are the values it gets curated/checked earlier?
Anyhow, don't get butt-hurt if I made a silly assumption or mistake. I'm
ignorant. Just trying to peek at the code and learn a bit.
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