From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1h0ihV-0002hY-UR for barebox@lists.infradead.org; Mon, 04 Mar 2019 08:11:55 +0000 Date: Mon, 4 Mar 2019 09:11:51 +0100 From: Sascha Hauer Message-ID: <20190304081151.y6ulieh6tzubicro@pengutronix.de> References: <3429d555-f746-f248-af2f-7e41022cf055@rempel-privat.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <3429d555-f746-f248-af2f-7e41022cf055@rempel-privat.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: Loading Barebox to RAM To: Oleksij Rempel Cc: Patrick Schneider , "barebox@lists.infradead.org" On Sat, Mar 02, 2019 at 03:36:51PM +0100, Oleksij Rempel wrote: > Hi, > > Am 02.03.19 um 13:49 schrieb Patrick Schneider: > > Hey guys, > > I have a question about a way of "emergency flashing" the device. > > So I have a fully operational linux system with barebox as bootloader. In production environment I have no access to the serial console but I have a USB OTG port. > > For security reasons I don't want USB active in my "normal" barebox environment, so it's off by config. > > For support, to gain access to a barebox and bootloader functionality is there a way to load another barebox (with usb active) from linux userspace into RAM and start/reboot into that? > > Have a nice weekend! > > Let me rephrase: you disabled every thing in a bootloader which can be > accessed only locally and provided functional to nuke complete system > from linux which can be accessed locally and remotely? > I assume, it would make sense to review the thread model of this project. > > Any way. "is it possible to run barebox from linux", the answer would > be: theoretically it should be possible to do it from kexec. I never > tried it before. I tried it on ARM and it used to work. Of course you need a barebox that doesn't try to bringup the SDRAM you are currently running at, but most code in barebox tests the PC being outside SDRAM before setting it up. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox