From owner-freebsd-hackers@freebsd.org Sat Mar 9 15:26:32 2019 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id F143B1529B52 for ; Sat, 9 Mar 2019 15:26:31 +0000 (UTC) (envelope-from hps@selasky.org) Received: from mail.turbocat.net (turbocat.net [88.99.82.50]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id C30F98BE9B for ; Sat, 9 Mar 2019 15:26:30 +0000 (UTC) (envelope-from hps@selasky.org) Received: from hps2016.home.selasky.org (unknown [176.74.212.121]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.turbocat.net (Postfix) with ESMTPSA id 3B1A32603CF; Sat, 9 Mar 2019 16:26:21 +0100 (CET) Subject: Re: USB stack getting confused To: "O'Connor, Daniel" Cc: FreeBSD Hackers References: <3B29D870-41F9-46AF-B9F3-03106DEC417D@dons.net.au> From: Hans Petter Selasky Message-ID: <6dd8fe5f-6835-d98a-7592-0293406ccd63@selasky.org> Date: Sat, 9 Mar 2019 16:25:58 +0100 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:60.0) Gecko/20100101 Thunderbird/60.4.0 MIME-Version: 1.0 In-Reply-To: <3B29D870-41F9-46AF-B9F3-03106DEC417D@dons.net.au> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: C30F98BE9B X-Spamd-Bar: ------ Authentication-Results: mx1.freebsd.org; spf=pass (mx1.freebsd.org: domain of hps@selasky.org designates 88.99.82.50 as permitted sender) smtp.mailfrom=hps@selasky.org X-Spamd-Result: default: False [-6.55 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; FROM_HAS_DN(0.00)[]; R_SPF_ALLOW(-0.20)[+a:mail.turbocat.net]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[selasky.org]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; MX_GOOD(-0.01)[cached: mail.turbocat.net]; RCPT_COUNT_TWO(0.00)[2]; NEURAL_HAM_SHORT(-0.96)[-0.963,0]; IP_SCORE(-3.28)[ip: (-9.49), ipnet: 88.99.0.0/16(-4.66), asn: 24940(-2.23), country: DE(-0.01)]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:24940, ipnet:88.99.0.0/16, country:DE]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 09 Mar 2019 15:26:32 -0000 On 3/9/19 11:29 AM, O'Connor, Daniel wrote: > If I hold the user space process in gdb 'forever' (eg over night) usbconfig doesn't see the device, but the moment I quit the user space process it can be seen again. Check the output from "procstat -ak". Likely your application is not closing the USB handle during device detach and so a deadlock happens. Also see: libusb20_dev_check_connected() . Poll this function regularly to figure out if disconnect is needed. --HPS