From owner-freebsd-wireless@FreeBSD.ORG Sun Nov 10 02:46:53 2013 Return-Path: Delivered-To: freebsd-wireless@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTP id 97CD72BA; Sun, 10 Nov 2013 02:46:53 +0000 (UTC) (envelope-from adrian.chadd@gmail.com) Received: from mail-qc0-x231.google.com (mail-qc0-x231.google.com [IPv6:2607:f8b0:400d:c01::231]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 4815820F5; Sun, 10 Nov 2013 02:46:53 +0000 (UTC) Received: by mail-qc0-f177.google.com with SMTP id b10so807469qcw.36 for ; Sat, 09 Nov 2013 18:46:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=4UG5nlmYxNK3xvZyyWTdB42dbKKwLUYFuk13IgDSHr4=; b=F/LRxzfgPCV5w1gOddIK5lNQAJ2ZGYPwc2vGYBys7YMDJqvQT7uYRvT7F26y37lJN6 Nkj6xZ/Bfu2EQFeQAy3AUoKm4Hg1CmIqDjkZrmscrTCvgKmSO445rAo9hvopK46cqen3 kMP813uOQ/cBnbiywetKkVbqNMVa+QK9FGHEcS7bSbCGzaZUKsZfHFc171BUK07iwQXZ fLU7Ub2orUrlkH2H4igRbP2OTbpW9iOxZOFpA1yGdWW8leD8ldHddJA2OpzJMp2feR8z Qx/q0o4R5EAkHgrk/tM0MObFltxjunxhHdAi6QPZr6K0WqhpFv+CoIkDUMX/Dgvlu5mH jZWA== MIME-Version: 1.0 X-Received: by 10.224.28.130 with SMTP id m2mr36627690qac.98.1384051612539; Sat, 09 Nov 2013 18:46:52 -0800 (PST) Sender: adrian.chadd@gmail.com Received: by 10.224.207.66 with HTTP; Sat, 9 Nov 2013 18:46:52 -0800 (PST) In-Reply-To: References: Date: Sat, 9 Nov 2013 18:46:52 -0800 X-Google-Sender-Auth: 8AOEOwHf3l0Y9jjERyrAjDQDoSg Message-ID: Subject: Re: iwn(4) hangs after r257133 From: Adrian Chadd To: Brandon Gooch , "freebsd-wireless@freebsd.org" Content-Type: text/plain; charset=ISO-8859-1 Cc: FreeBSD Current X-BeenThere: freebsd-wireless@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: "Discussions of 802.11 stack, tools device driver development." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 10 Nov 2013 02:46:53 -0000 Hi! On 9 November 2013 18:29, Brandon Gooch wrote: > Turns out that not enabling MRR causes my Intel Ultimate N WiFi Link > 5300 to hang after only a few moments of use. That's .. odd. Ok. > For now, I've just reverted only those aspects of r257133, enabling > MRR and keeping the rate index lookup, which seems to do something on > my hardware at least (I assume it's not the right thing based on > Adrian's analysis, but it works never-the-less). > > Has anyone else hit this with Intel WiFi hardware? > > Also, what needs to be done to have MRR working properly? So, it could be a fall out of how utterly crap AMRR is at 11n rates. Please compile with IWN_DEBUG, then do this before you associate: sysctl dev.iwn.0.debug=0x1 (that's IWN_DEBUG_XMIT in sys/dev/iwn/if_iwn_debug.h) You can do the same on a kernel with and without the MRR stuff enabled. I'd like to see what the actual rate selection looks like and what the final rate selection is. We may have to patch the kernel to print out the contents of 'rate' and 'tx->rate' in iwn_tx_data() to get that. The MRR stuff is a bit special. I don't know how the link table works in great depth yet. I know it's broken for 11n; it's plainly using the wrong indexes now. That's why I disabled it. It shouldn't take that much work to get it in the tree again; it'll just be fiddly. The easy bit is populating the table. The hard bit is knowing which index to set linkq to when transmitting a frame. -adrian