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Date: Sun, 26 Sep 2004 11:24:43 -0600 (MDT)
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To: phk@phk.freebsd.dk
From: "M. Warner Losh" <imp@bsdimp.com>
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cc: arch@freebsd.org
Subject: Re: I'm counting my threads, one, two, three, four, five... [1]
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In message: <41458.1096016465@critter.freebsd.dk>
            "Poul-Henning Kamp" <phk@phk.freebsd.dk> writes:
: I belive this gives us the handle we need to unload drivers and remove
: hardware without panicing in the lower layers of the kernel.  The
: higher layers may still have a thing or two to learn in this respect.

I've been extremely worried about the dev interface into the driver
for a long time.  This proposal looks excellent, and I can't think of
anything else to add to it.  It is good to see all the concerns in
this area you and I have talked about over the years appear to be
addressed by this.

The biggest problem now is that I need to address the device_t level
locking.  I think with network layer locking and dev_t locking being
under control, it is close to time to tackle it.

The other big problem may happen in the device detach routines of
bus drivers not being happy with new-found sleeps.

However, these two problems always existed :-(

Well done!

Warner