Interrupt Problems

[Matthew Fleming]

David Naylor wrote:
> I have been having interrupt related problems with various subsystems.  I
> suspect this is related to the changes in the event timer infrastructure.
>
> The subsystems that have experienced interrupt problems:
>  - hda: this is the easiest to reproduce and what I used to isolate the
> commits.  I get ``pcm0: chn_write(): pcm0:virtual:dsp0.vp0: play interrupt
> timeout, channel dead'' reported and sound no longer plays.
>  - nfe: this has happened on occasion with no reliable way to reproduce.
> ``watchdog timeouts'' are reported.  After this happens all network traffic dies
> and doing `ifconfig nfe0 down; ifconfig nfe0 up' panics the computer.
>  - dc: same thing as above.
>  - nvidia: has reported interrupt timeouts.  This is independent of the
> locking problem (that is fixed with recently published patch).  No reliable way
> to reproduce, appears to happen when under heavy load.  X freezes as a result.
>  - ata: I had a HDD detach twice.  I am not sure if this is related.  I have
> two HDD, each attached to a different controller.
>
> I tested this by using a kernel built from a cvsup date of 2010/06/20 and
> 2010/06/22 (at midnight for both, aka 00:00:00).  The former kernel does not
> exhibit any problems while the latter does.  This problem is also present with
> a kernel from today.
>
> The motherboard is a N650SLI-DS4L with one graphics card.  See attached for
> more system information.
>
> Is there anything I can do to help diagnose the problem?

When you say midnight on June 22, is that 11:59pm June 22 or 12:01 am June 22?

I don't expect it, but there's a possibility that r210377 affected
this.  Can you check whether sys/sys/_task.h changes between the
kernel that does work and the one that doesn't?

Thanks,
matthew