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Date: Fri, 16 Sep 2011 16:30:08 +0300
From: Andriy Gapon <avg@FreeBSD.org>
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To: Boris Kochergin <spawk@acm.poly.edu>
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Cc: freebsd-current <freebsd-current@FreeBSD.org>
Subject: Re: Thinkpad CD-ROM hotplug with ATA_CAM
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on 16/09/2011 15:55 Boris Kochergin said the following:
> On 09/14/11 12:15, Andriy Gapon wrote:
>> on 14/09/2011 18:11 Boris Kochergin said the following:
>>> camcontrol rescan all
>> I think that this command may screw up communication between kernel and HDD from
>> which the OS runs.
> 
> It works under normal circumstances--I can run "camcontrol rescan all" on a system
> with ATA_CAM and the root filesystem isn't disturbed.
> 
>> Perhaps using a specific bus number would work better.
>>
> 
> Somewhat, but results are still undesirable. "camcontrol rescan 1" (the CD-ROM is
> listed as being on scbus1) executes, stays in the cbwait state for 30 seconds,
> then the system locks up.
> 
> "camcontrol reset 1" has the same behavior as "camcontrol rescan all" in that the
> system locks up instantly.

Weird.  Can you provoke a panic when that happens?
Maybe you can contact mav@ directly and he'd be interested in debugging this case.


-- 
Andriy Gapon