From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1ZyNrM-0003v1-5L for user-mode-linux-devel@lists.sourceforge.net; Mon, 16 Nov 2015 17:46:32 +0000 Received: from userp1040.oracle.com ([156.151.31.81]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1ZyNrL-0007kP-AB for user-mode-linux-devel@lists.sourceforge.net; Mon, 16 Nov 2015 17:46:32 +0000 References: <5649A525.9010404@oracle.com> <5649C186.7080106@nod.at> <5649C2D9.90407@oracle.com> <564A1339.8010607@nod.at> From: Vegard Nossum Message-ID: <564A166A.5080504@oracle.com> Date: Mon, 16 Nov 2015 18:46:18 +0100 MIME-Version: 1.0 In-Reply-To: <564A1339.8010607@nod.at> List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: user-mode-linux-devel-bounces@lists.sourceforge.net Subject: Re: [uml-devel] WARNING: CPU: 0 PID: 908 at include/linux/thread_info.h:128 sigsuspend+0xab/0xc0() To: Richard Weinberger , Jeff Dike Cc: user-mode-linux-devel@lists.sourceforge.net On 11/16/2015 06:32 PM, Richard Weinberger wrote: > Am 16.11.2015 um 12:49 schrieb Vegard Nossum: >> On 11/16/2015 12:44 PM, Richard Weinberger wrote: >>> Am 16.11.2015 um 10:43 schrieb Vegard Nossum: >>>> Starting UML like this: >>>> >>>> ./vmlinux rootfstype=hostfs rw ignore_console_loglevel con=xterm init=/bin/bash >>>> >>>> Results in unpredictable behaviour, most of the time an xterm flashes on >>>> my screen but the process aborts with only "Aborted" on the console >>>> where I ran the command, sometimes the xterm remains there but frozen, >>>> sometimes the xterm spews this warning non-stop: >>> >>> Hmm, is this a new regression? >>> I bet it only happens with con=xterm, right? >> >> It's the first UML kernel I compile in a few years, so I don't know if >> it's old or new, sorry. >> >> Yes, only con=xterm triggers this. > > /me found some odd stuff. > > arch/um/drivers/chan_user.c tries to call sigsuspend() on the host side. > But sadly the kernel has also a function with the same name. > So, chan_user.c calls into the UML kernel instead of the host. > This seems to work by accident but confuses the Linux signal logic > and you trigger from time to time the WARN_ON(). > > From a quick look, the kernel sigsuspend() has no users except in the same > object file. So we can mark it static and UML calls the real one. > > Does the attached patch help? > I'm sure we need more work as this clearly never worked as expected. :-( Perfect, with your patch xterm works every time. (With the earlyprintk tip you gave earlier, I was also able to use con0=pts -- con0=pty doesn't seem to find any host devices, but that's probably expected.) Thanks a lot! Vegard ------------------------------------------------------------------------------ Presto, an open source distributed SQL query engine for big data, initially developed by Facebook, enables you to easily query your data on Hadoop in a more interactive manner. Teradata is also now providing full enterprise support for Presto. Download a free open source copy now. http://pubads.g.doubleclick.net/gampad/clk?id=250295911&iu=/4140 _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel