The process in question is jackd, and once this stuck state is reached one
cannot even start a new instance of jack which leads me to believe this is
a jack issue, particularly considering this is not a problem on Ubuntu
12.04 where you could still kill the process under these circumstances,
even though I still don't think allowing jack to get stuck like this is the
best approach to dealing with an issue like this, however unlikely it may
be. Now, it may be a case of bad packaging or some out-of-date version,
but given the circumstances I'm not convinced this is an alsa issue at this
point in time.
-- Ivica Ico Bukvic, D.M.A. Associate Professor Computer Music ICAT Senior Fellow Director -- DISIS, L2Ork Virginia Tech School of Performing Arts – 0141 Blacksburg, VA 24061 (540) 231-6139 ico@email-addr-hidden www.performingarts.vt.edu disis.icat.vt.edu l2ork.icat.vt.edu Ico.bukvic.net On Oct 17, 2015 2:44 PM, "Fons Adriaensen" <fons@email-addr-hidden> wrote: > On Sat, Oct 17, 2015 at 07:24:02PM +0100, Will Godfrey wrote: > > On Sat, 17 Oct 2015 13:58:37 -0400 > > Ivica Ico Bukvic <ico@email-addr-hidden> wrote: > > > > > Hi all, > > > > > > This is a long-standing problem. While it is not intentional, sometimes > > > newcomers to jack on Linux tend to pull out the soundcard (USB) before > > > shutting down jack. This results in jack permanently hanging to the > > > point where one has to force-shutdown the machine. That is at least the > > > case on Ubuntu 14.04 (and was on 12.04) with lowlatency kernel. Trying > > > to do sudo killall -9 jackd makes no difference. Essentially, it is > > > impossible to destroy the process and reboot hangs because of it. > > > > > > Any idea what can be done to minimize this problem or alleviate it > > > altogether? > > > > > > Best, > > > > > > Ico > > > > > > a workaround is from a terminal type: > > > > pidof jackd > > > > you'll get a number such as 3772 > > > > then type > > > > kill -9 3772 > > That's what killall or pkill will do anyway, so > I don't think this is a solution. > > I also don't think that Jack is involved. You'd > probably get the same effect when unplugging the > USB device while some ALSA app is using it. > > There is a similar problem with the hdsp-madi module, > and it has hit me a number of times when installing > the card in a new system. Apparently the default > configuration expects an external clock, and when > that isn't connected any process that uses the device > hangs and can't be killed. The first process to do so > will be alsactl, called as part of the boot sequence. > And since that will be called again as part of reboot > or poweroff, those will hang as well. The only thing > you can do to pull the power plug, remove the card, > boot, edit the file used by alsactl, switch off, put > the card back and boot. > > Ciao, > > -- > FA > > A world of exhaustive, reliable metadata would be an utopia. > It's also a pipe-dream, founded on self-delusion, nerd hubris > and hysterically inflated market opportunities. (Cory Doctorow) > > _______________________________________________ > Linux-audio-user mailing list > Linux-audio-user@email-addr-hidden > http://lists.linuxaudio.org/listinfo/linux-audio-user >
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Received on Sun Oct 18 04:15:01 2015
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