Matthew Dillon dillon at
Mon Feb 25 08:11:02 PST 2008

:Hello Matt,
:I see a weird issue with snd_hda. It doesn't work on SMP with interrupts.
:It does work on a UP kernel in the same box, also works on SMP if i
:enable hw.snd.pcm0.polling. In the output of vmstat -i i don't see any
:interrupt being generated. Also when i try to play something in SMP
:mode without polling i get this error on dmesg:
:pcm0:virtual:0:dsp0.2: play interrupt timeout, channel dead
:Any idea on what could be wrong and how can i fix it?

    I'm guessing you are building your SMP box with options APIC_IO ?
    If so you can try building it without APIC_IO.

    Interrupt routing is still an area we are very weak in.  That and
    64 bit support and progress in the SMP locking code.

    But for the first half of this year and particularly with respect to
    the mid-year 2.0 release DragonFly needs a distinguishing feature for
    itself that no other BSD has, and HAMMER is my focus.

					Matthew Dillon 
					<dillon at>

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