From owner-freebsd-arch@FreeBSD.ORG Sun Dec 22 19:28:50 2013 Return-Path: Delivered-To: freebsd-arch@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 ESMTPS id B9D057FA; Sun, 22 Dec 2013 19:28:50 +0000 (UTC) Received: from h2.funkthat.com (gate2.funkthat.com [208.87.223.18]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 7919F12C4; Sun, 22 Dec 2013 19:28:50 +0000 (UTC) Received: from h2.funkthat.com (localhost [127.0.0.1]) by h2.funkthat.com (8.14.3/8.14.3) with ESMTP id rBMJSgl0003934 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sun, 22 Dec 2013 11:28:42 -0800 (PST) (envelope-from jmg@h2.funkthat.com) Received: (from jmg@localhost) by h2.funkthat.com (8.14.3/8.14.3/Submit) id rBMJSg1K003933; Sun, 22 Dec 2013 11:28:42 -0800 (PST) (envelope-from jmg) Date: Sun, 22 Dec 2013 11:28:42 -0800 From: John-Mark Gurney To: Warner Losh Subject: mountroot issues (was Re: 10.0-release proposed patch for Atmel) Message-ID: <20131222192842.GI99167@funkthat.com> Mail-Followup-To: Warner Losh , "freebsd-arm@freebsd.org" , freebsd-arch@FreeBSD.org References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.3i X-Operating-System: FreeBSD 7.2-RELEASE i386 X-PGP-Fingerprint: 54BA 873B 6515 3F10 9E88 9322 9CB1 8F74 6D3F A396 X-Files: The truth is out there X-URL: http://resnet.uoregon.edu/~gurney_j/ X-Resume: http://resnet.uoregon.edu/~gurney_j/resume.html X-to-the-FBI-CIA-and-NSA: HI! HOW YA DOIN? can i haz chizburger? X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.2 (h2.funkthat.com [127.0.0.1]); Sun, 22 Dec 2013 11:28:42 -0800 (PST) Cc: "freebsd-arm@freebsd.org" , freebsd-arch@freebsd.org X-BeenThere: freebsd-arch@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: Discussion related to FreeBSD architecture List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 22 Dec 2013 19:28:50 -0000 Warner Losh wrote this message on Sat, Dec 21, 2013 at 23:44 -0700: > Right now, the mountroot prompt doesn't work on Atmel CPUs. Almost all the characters are eaten. I recently committed an elegant fix for this into head to mask the interrupt for new characters and only do polling. So, a similar issue plages i386/amd64 too. There the console mostly works, but it will drop characters on occasion... The problem is that mount root spins calling into the console code instead of asking the console code for a single character and having the console code wait for this character... and if you type a character while it's outside the console routines, that character will be dropped... The problem is, not many of us spend time at the mountroot prompt, and so even if we notice the issue, it's so minor that we just deal w/ it... The method I came up with years ago was to add a routine/flag that would have the console wait for a character instead of simply returning when there was no character... Though if we implement cngrab properly where we don't flush buffers, turn off interupts, etc, then that would work too... I've cc'd -arch since it's not just an -arm issue. -- John-Mark Gurney Voice: +1 415 225 5579 "All that I will do, has been done, All that I have, has not."