From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52787) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fAydW-00050G-7x for qemu-devel@nongnu.org; Tue, 24 Apr 2018 10:09:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fAydR-0007Ta-9F for qemu-devel@nongnu.org; Tue, 24 Apr 2018 10:09:38 -0400 Date: Tue, 24 Apr 2018 16:09:11 +0200 From: Cornelia Huck Message-ID: <20180424160911.22a238bb.cohuck@redhat.com> In-Reply-To: <87f6ba73-2ded-06f2-c68f-d8ef4be50edf@redhat.com> References: <1524570294-23058-1-git-send-email-thuth@redhat.com> <87f6ba73-2ded-06f2-c68f-d8ef4be50edf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [RFC PATCH] hw/s390x: Allow to configure the consoles with the "-serial" parameter List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Thomas Huth Cc: Christian Borntraeger , qemu-s390x@nongnu.org, qemu-devel@nongnu.org, David Hildenbrand , Eduardo Habkost , Marcel Apfelbaum , Paolo Bonzini On Tue, 24 Apr 2018 16:02:59 +0200 Thomas Huth wrote: > On 24.04.2018 13:49, Christian Borntraeger wrote: > > > > > > On 04/24/2018 01:44 PM, Thomas Huth wrote: > >> The consoles ("sclpconsole" and "sclplmconsole") can only be configured > >> with "-device" and "-chardev" so far. Other machines use the convenience > >> option "-serial" to configure the default consoles, too, even for virtual > >> consoles like spapr-vty on the pseries machine. So let's support this > >> option on s390x, too, so we can easily enable the serial console here > >> again with "-nodefaults", for example. Also map the second -serial > >> option to the "sclplmconsole", so that there is now an easy way to > >> configure this second console on s390x, too. > >> Additionally, the new code is also smaller than the old one and we have > >> less s390x-specific code in vl.c :-) > > > > Can you show some new example command lines? > > Sure. I'm mainly using this together with nodefaults: > > qemu-system-s390x -no-shutdown -nographic -nodefaults -serial mon:stdio > > That's way easier than typing: > > qemu-system-s390x -no-shutdown -nographic -nodefaults \ > -chardev stdio,id=c1,mux=on -device sclpconsole,chardev=c1 \ > -mon chardev=c1 What, you don't like typing complicated command lines? :) > > Another example: You only want to see the QEMU monitor on stdio, but not > the serial output, without using -nodefaults (i.e. you still want to > have the other default devices). AFAIK that's pretty impossible with the > current code. But once you've got this patch applied, you can do: > > qemu-system-s390x -no-shutdown -nographic -serial none > > And to view the sclplm console, you can now simply do: > > qemu-system-s390x -no-shutdown -nographic -serial null -serial mon:stdio Looks cool. Maybe add some of the examples to the patch description? > > > I read that as "the current command lines continue to work". Correct? > > Right. I was a little bit afraid that this might break migration, but I > gave it a quick check and it still seems to work fine here. > "info qom-tree" and "info qtree" at the HMP monitor show slightly > different output, though ... not sure whether that's critical or not? What looks different? If we still send/expect the same kind of information, it should not have any impact, I guess.