SCSI device not created upon a CF card plug in

[Peter C. Lai]

GEOM should pick up the state change, but the bug may continue to exist
because the CF reader is tagged as a storage device with invalid media
when umass attaches to it on startup; there wasn't a really good way to
actually enumerate the slice table upon insertion because the device
does not send a disconnect/reconnect to the bus when you insert the
card. At the time, the workaround was to tickle the device by attempting
a mount against the whole disk, then the slice table will be enumerated.

Example, CF card reader on boot will be picked up as /dev/da4
You insert card, no state change can be detected because the device
doesn't get reset on the bus.
mount /dev/da0 /mnt <-- will fail for obvious reasons, but now slices
are enumerated
mount /dev/da0s1f /mnt/mycfcard <-- ok

On 2009-07-23 06:24:17PM +0300, Andriy Gapon wrote:
> on 23/07/2009 17:14 Kevin Oberman said the following:
> > If Linux detects media insertion instantly or Windows detects media
> > insertion instantly (which I can confirm), there is some signal
> > available, so looking at the Linux driver should provide a clue as to
> > what to look for and that can be added to the FreeBSD umass driver. It
> > would be a very desirable addition, but I am not volunteering as I
> > currently don't use such devices. (And, no one would like the terrible
> > code I would write, anyway.)
> 
> Just a note of caution: human "instant" is different from "computer instant".
> If OS driver polls, say, every 0.2 seconds, you won't be able to tell the difference.
> 
> -- 
> Andriy Gapon
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-- 
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Peter C. Lai                 | Bard College at Simon's Rock
Systems Administrator        | 84 Alford Rd.
Information Technology Svcs. | Gt. Barrington, MA 01230 USA
peter AT simons-rock.edu     | (413) 528-7428
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