From owner-cvs-src@FreeBSD.ORG Wed Mar 28 21:47:23 2007 Return-Path: <owner-cvs-src@FreeBSD.ORG> 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 DA72C16A401 for <cvs-src@freebsd.org>; Wed, 28 Mar 2007 21:47:23 +0000 (UTC) (envelope-from minimarmot@gmail.com) Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.248]) by mx1.freebsd.org (Postfix) with ESMTP id 9774313C45E for <cvs-src@freebsd.org>; Wed, 28 Mar 2007 21:47:23 +0000 (UTC) (envelope-from minimarmot@gmail.com) Received: by an-out-0708.google.com with SMTP id c24so2836562ana for <cvs-src@freebsd.org>; Wed, 28 Mar 2007 14:47:23 -0700 (PDT) DKIM-Signature: a=rsa-sha1; c=relaxed/relaxed; d=gmail.com; s=beta; h=domainkey-signature:received:received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=aIemjqZ+aauTKJaasQdU8lJEkvjsjlnQkqW5h6OYw1HPJ37cEjuF5qi/RN0e5rPb2i2PI1kIBIJXp4Bw8Umaiu+1x3oAIwjApmVcH6+WFdpP4QvSplkL1dfdOIKM4C7cnzkR7w/UtC0+mXjK+/LlV+dQaBYuFD7lMsDdGKYSAXQ= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=beta; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=EypA4H13f80jP/waK/MshIYJ9c/OapIeojxLzG4RhXmODyg3gtzbmt4QRMi6lDkXbzw+ywypM960iZZQ9CILygSbRWBEMa0Nsp2jDZ3EVQPImujGjwm3WkCcNy3HPlQTpTjI2CoGXmoQt8Mhw0Zy4BZUDweTFR/+Elpfz2QK2cc= Received: by 10.100.35.17 with SMTP id i17mr652830ani.1175116791810; Wed, 28 Mar 2007 14:19:51 -0700 (PDT) Received: by 10.100.241.6 with HTTP; Wed, 28 Mar 2007 14:19:51 -0700 (PDT) Message-ID: <47d0403c0703281419n22d73ba0u528df488bc8afc8b@mail.gmail.com> Date: Wed, 28 Mar 2007 16:19:51 -0500 From: "Ben Kaduk" <minimarmot@gmail.com> To: "Marcel Moolenaar" <marcel@freebsd.org> In-Reply-To: <200703281826.l2SIQDTN060321@repoman.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <200703281826.l2SIQDTN060321@repoman.freebsd.org> Cc: cvs-src@freebsd.org, 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 <cvs-src.freebsd.org> List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src>, <mailto:cvs-src-request@freebsd.org?subject=unsubscribe> List-Archive: <http://lists.freebsd.org/pipermail/cvs-src> List-Post: <mailto:cvs-src@freebsd.org> List-Help: <mailto:cvs-src-request@freebsd.org?subject=help> List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/cvs-src>, <mailto:cvs-src-request@freebsd.org?subject=subscribe> X-List-Received-Date: Wed, 28 Mar 2007 21:47:23 -0000 On 3/28/07, Marcel Moolenaar <marcel@freebsd.org> 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? I am under the impression that debug ports can do such things as break to the debugger and access arbitrary memory, which a console is not guaranteed to be able to do. -Ben Kaduk [snip]