kern/150186: [parallels] [panic] Parallels Desktop: CDROM disconnected leads to panic, eventually

[Ivan Voras]

On 12/16/10 20:27, Adam Vande More wrote:
> On Thu, Dec 16, 2010 at 1:20 PM, Li-Lun Wang (Leland Wang)<llwang at infor.org
>> wrote:
>
>>    I think I may have stumbled upon the same issue after I updated my
>>   installed ports, including hald.  I run a FreeBSD 8.1-stable amd64 (not
>>   the latest but a few months old) in virtual box on a windows 7 x64
>>   host.  If I disable hald or the cdrom device in virtual box, or run the
>>   same FreeBSD installation natively, the problem doesn't seem to occur.
>>   When the problem does occur, I get the following messages (not
>>   necessarily in any particular order):
>>
>>   ata0: WARNING - unknown CMD (0x4a) read data overrun 18>8
>>   ata0: WARNING - READ_TOC read data overrun 18>12
>>   ata0: WARNING - PREVENT_ALLOW read data overrun 18>0
>>   ata0: WARNING - TEST_UNIT_READY read data overrun 18>0
>>
>>   These messages repeat seemingly at random for a few times.  Eventually
>>   the box might panic.
>
> Interesting, I also found the same to be true.

I'd say it's "well known" - at least the panic also happens on VMWare, 
and has been happening for many years.