From owner-cvs-src@FreeBSD.ORG Wed Mar 28 21:53:30 2007 Return-Path: X-Original-To: cvs-src@freebsd.org Delivered-To: cvs-src@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 7AB3616A400; Wed, 28 Mar 2007 21:53:30 +0000 (UTC) (envelope-from xcllnt@mac.com) Received: from smtpout.mac.com (smtpout.mac.com [17.250.248.176]) by mx1.freebsd.org (Postfix) with ESMTP id 5EFF013C4BE; Wed, 28 Mar 2007 21:53:30 +0000 (UTC) (envelope-from xcllnt@mac.com) Received: from mac.com (smtpin08-en2 [10.13.10.153]) by smtpout.mac.com (Xserve/smtpout06/MantshX 4.0) with ESMTP id l2SLrT0X003371; Wed, 28 Mar 2007 14:53:30 -0700 (PDT) Received: from [172.24.104.91] (natint3.juniper.net [66.129.224.36]) (authenticated bits=0) by mac.com (Xserve/smtpin08/MantshX 4.0) with ESMTP id l2SLrQCw025146 (version=TLSv1/SSLv3 cipher=AES128-SHA bits=128 verify=NO); Wed, 28 Mar 2007 14:53:27 -0700 (PDT) In-Reply-To: <47d0403c0703281419n22d73ba0u528df488bc8afc8b@mail.gmail.com> References: <200703281826.l2SIQDTN060321@repoman.freebsd.org> <47d0403c0703281419n22d73ba0u528df488bc8afc8b@mail.gmail.com> Mime-Version: 1.0 (Apple Message framework v752.3) Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Message-Id: Content-Transfer-Encoding: 7bit From: Marcel Moolenaar Date: Wed, 28 Mar 2007 14:52:44 -0700 To: Ben Kaduk X-Mailer: Apple Mail (2.752.3) X-Brightmail-Tracker: AAAAAA== X-Brightmail-scanned: yes Cc: cvs-src@freebsd.org, Marcel Moolenaar , src-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/sys/dev/uart uart_core.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Mar 2007 21:53:30 -0000 On Mar 28, 2007, at 2:19 PM, Ben Kaduk wrote: > On 3/28/07, Marcel Moolenaar wrote: >> marcel 2007-03-28 18:26:12 UTC >> >> FreeBSD src repository >> >> Modified files: >> sys/dev/uart uart_core.c >> Log: >> When we match UARTs found during bus-enumeration with UARTs used >> for >> system devices (i.e. console, debug port or keyboard), don't stop >> after the first match. Find them all and keep track of the last. >> The reason for this change is that the low-level console is always >> added to the list of system devices first, with other devices added >> later. Since new devices are added to the list at the head, we have >> the console always at the end. When a debug port is using the same >> UART as the console, we would previously mark the "newbus" UART as >> a debug port instead of as a console. This would later result in a >> panic because no "newbus" device was associated with the console. >> By matching all possible system devices we would mark the "newbus" >> UART as a console and not as a debug port. >> While it is arguably better to be able to mark a "newbus" UART as >> both console and debug port, this fix is lightweight and allows >> a single UART to be used as the console as well as a debug port >> with only the aesthetic bug of not telling the user about it also >> being a debug port. >> > > I am rather ignorant about such things, but is there any security risk > in having an "undocumented" debug port? There's no security issue. The user/administrator has to configure the machine and/or kernel before there will be a UART-based debug port. The kernel will announce when uart is used as a debug port. There's just a particular case when the uart port in question will not announce that it's the debug port. FYI, -- Marcel Moolenaar xcllnt@mac.com