suspend/resume and the freebsd usb stack

[Ian Smith]

On Fri, 30 Jul 2010, Hans Petter Selasky wrote:
 > On Friday 30 July 2010 16:53:22 b. f. wrote:
 > > Are these criticisms of suspend/resume for the usb stack justified?:
 > > 
 > > http://lists.freebsd.org/pipermail/svn-src-head/2010-July/018974.html
 > > 
 > > If so, are there any plans to fix the problem(s)?
 > > 
 > > Regards,
 > >                b.
 > 
 > Hi,
 > 
 > Suspend and resume has not been too much tested! Some part is done in the 
 > BIOS, the other part is done in the OS. You can try doing a detach instead of 
 > a suspend, and an attach instead of a resume.

Do you mean doing what you often used to have to do with the old usb 
stack, at least on some laptops, that is kldunload usb before suspend 
and kldload usb after resume, in /etc/rc.{suspend,resume} respectively?

If so, how would that go if (eg) you had a USB stick or external drive 
mounted?  And with usb in kernel, I guess you can't unload it anyway?

I know doing that used to cause panics, but admit not having tried it 
more recently, except one suspend/resume (default rc.{suspend,resume}) 
from the Fixit shell booted from the 8.1-RELEASE-i386-memstick.img the 
other night, where I got I/O read errors on commands, that ceased after 
removing/reinserting the mounted stick (which WAS quite encouraging :)

If not, what/how do you mean by detach and attach here?

 > Patches are welcome!

First don't we need to describe just what the problems really are?

cheers, Ian