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
