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Subject: Re: USB stack getting confused
To: Konstantin Belousov <kostikbel@gmail.com>
Cc: Warner Losh <imp@bsdimp.com>,
 FreeBSD Hackers <freebsd-hackers@freebsd.org>,
 "O'Connor, Daniel" <darius@dons.net.au>
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From: Hans Petter Selasky <hps@selasky.org>
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Date: Sun, 10 Mar 2019 11:18:36 +0100
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On 3/10/19 10:47 AM, Konstantin Belousov wrote:
>> Yes, I can do that if destroy_dev() ensures that d_close is called for
>> all open file handles once and only once before it returns. I think this
>> is where the problem comes from.
> See above.  For d_close it is impossible, for cdevpriv dtr it is already
> there by design.
> 

Yes, cdevpriv_dtr will wait for the final close() from user-space 
unfortunately. Or am I mistaken?

--HPS