RELENG_5: ata interrupt problems

[Randy Bush]

> The actual errors from a 5.3-BETA from today (hand transcribed):

thanks for the transcription; i have tendonitis

> ad0: 73863MB <HTS548080M9AT00/MG40A50A> [150071/16/63] at ata0-master UDMA100
> ATAPI_RESET time = 150us
> ata1-slave: FAILURE - ATAPI_IDENTIFY timed out
> ATAPI_RESET time = 150us
> acd0: CDRW <UJDA740 DVD/CDRW/1.04> at ata1-master UDMA33
> Mounting root from ufs:/dev/ad0s2a
> [...]
> ad0: WARNING - READ_DME interupt was seen but timeout fired LBA=41574224
> [...]
> ad0: WARNING - READ_DME interupt was seen but timeout fired LBA=41562160
> ad0: WARNING - READ_DME interupt was seen but timeout fired LBA=41562160
> ad0: WARNING - READ_DME interupt was seen but taskqueue stalled LBA=41562160
> Slab at 0xc1c3ff70, freei 3 = 0
> 
> The "[...]" is just normal startup.  It goes as far as the script that
> attaches my GDBE partition before it panics.
> 
> And then it panics like below:

yep.  same on a thinkpad t40p

randy