From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39085) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aUF27-00014H-8r for qemu-devel@nongnu.org; Fri, 12 Feb 2016 09:49:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aUF23-0005hz-HQ for qemu-devel@nongnu.org; Fri, 12 Feb 2016 09:49:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:34292) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aUF23-0005hb-BT for qemu-devel@nongnu.org; Fri, 12 Feb 2016 09:49:15 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id C972D3F3C9 for ; Fri, 12 Feb 2016 14:49:14 +0000 (UTC) Date: Fri, 12 Feb 2016 14:49:11 +0000 From: "Daniel P. Berrange" Message-ID: <20160212144911.GI24725@redhat.com> References: <20160211163539.506a5058@nial.brq.redhat.com> <20160212121526.599e75a6@nial.brq.redhat.com> <20160212111706.GD24725@redhat.com> <56BDD950.5000109@redhat.com> <20160212142723.53e31c6b@nial.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20160212142723.53e31c6b@nial.brq.redhat.com> Subject: Re: [Qemu-devel] broken HMP command: info mtree Reply-To: "Daniel P. Berrange" List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: Paolo Bonzini , qemu-devel@nongnu.org, dgilbert@redhat.com On Fri, Feb 12, 2016 at 02:27:23PM +0100, Igor Mammedov wrote: > On Fri, 12 Feb 2016 14:08:32 +0100 > Paolo Bonzini wrote: > > > On 12/02/2016 12:17, Daniel P. Berrange wrote: > > > On Fri, Feb 12, 2016 at 12:15:26PM +0100, Igor Mammedov wrote: > > >> On Thu, 11 Feb 2016 16:35:39 +0100 > > >> Igor Mammedov wrote: > > >> > > >>> executing 'info mtree' from monitor prompt causes infinite loop > > >>> printing it over and over. > > >>> > > >>> to reproduce build current master adn run: > > >>> > > >>> qemu-system-x86_64 -monitor stdio > > >>> > > >>> and then execute 'info mtree' in monitor prompt > > >> > > >> it bisects to: > > >> > > >> commit 9894dc0cdcc397ee5b26370bc53da6d360a363c2 > > >> Author: Daniel P. Berrange > > >> Date: Tue Jan 19 11:14:29 2016 +0000 > > >> > > >> char: convert from GIOChannel to QIOChannel > > >> > > >> In preparation for introducing TLS support to the TCP chardev > > >> backend, convert existing chardev code from using GIOChannel > > >> to QIOChannel. This simplifies the chardev code by removing > > >> most of the OS platform conditional code for dealing with > > >> file descriptor passing. > > >> > > >> Signed-off-by: Daniel P. Berrange > > >> Message-Id: <1453202071-10289-3-git-send-email-berrange@redhat.com> > > >> Signed-off-by: Paolo Bonzini > > >> > > >> > > >> build with: > > >> ./configure --target-list=x86_64-softmmu --enable-debug > > >> on RHEL72ish host > > >> > > >> monitor output has to be stdio > > > > > > Sigh, so much pain from the chardev code. I'll investigate and send a > > > suitable patch asap. > > > > Hmm, I cannot reproduce this though. > Perhaps I'm affected because my stdout goes via remote ssh session. > > It looks like monitor tries to flush buffer but succeeds only partially > and returns with EAGAIN and on the next flush attempt it tries to > flush the same buffer again from the first byte again Yes, it turned out to need a moderately slow console like a distant ssh connection to trigger the EGAIN situation. I've just sent a patch. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|