Bug #2067

sound/pcm: "play interrupt timeout, channel dead"

Added by matthiasr over 5 years ago. Updated almost 2 years ago.

Status:NewStart date:
Priority:NormalDue date:
Assignee:-% Done:


Target version:4.0.x


this fixes a "pcm0:virtual:0:dsp0.2: play interrupt timeout, channel dead" error
and sound breaking off after a few seconds of playback I encountered on my
Thinkpad X40. It was discussed on freebsd-current in 2004[1] but that code is no
longer present in FreeBSD while we still have it.

The patch[2] removes a line fixing a channel timeout to 1 tick instead of the
value calculated immediately beforehand, thus restoring the calculation.

[1] http://lists.freebsd.org/pipermail/freebsd-current/2004-


#1 Updated by matthiasr over 5 years ago

Interestingly, this problem is gone for me on master even with the forced timeout.

#2 Updated by cnb almost 2 years ago

  • Description updated (diff)
  • Category set to Driver
  • Target version set to 3.8.0

This error has reappeared in 3.8

#3 Updated by dillon almost 2 years ago

  • Assignee deleted (0)

There are multiple problems here not the least of which being that a timeout of 1 tick is too low anyway, because it can wind up happening 1ns later (the next tick interrupt). So the minimum is 2 and the calculation also needs to average-up fractional results. I will commit a fix which calculates it properly.


#4 Updated by dillon almost 2 years ago

I've committed 29ca9567 to master and cherry-pick'd it over to the 4.0 release. Please test.


#5 Updated by cnb almost 2 years ago

I just upgraded to 4.0 release, the error is still present.

pcm0:virtual:1:dsp0.3: play interrupt timeout, channel dead


#6 Updated by cnb almost 2 years ago

  • Target version changed from 3.8.0 to 4.0.x

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