From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:36747) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLGTJ-0005K9-Tc for qemu-devel@nongnu.org; Mon, 08 Oct 2012 12:46:29 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TLGTI-0003GD-QD for qemu-devel@nongnu.org; Mon, 08 Oct 2012 12:46:25 -0400 Received: from goliath.siemens.de ([192.35.17.28]:28208) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TLGTI-0003G0-GU for qemu-devel@nongnu.org; Mon, 08 Oct 2012 12:46:24 -0400 Message-ID: <5073035A.7070800@siemens.com> Date: Mon, 08 Oct 2012 18:46:18 +0200 From: Jan Kiszka MIME-Version: 1.0 References: <506F1934.5000002@siemens.com> <506F207A.70805@siemens.com> <5072782E.9090707@siemens.com> <5072EEB7.2070408@redhat.com> <5072F125.3010204@siemens.com> <5072FF12.3020201@redhat.com> In-Reply-To: <5072FF12.3020201@redhat.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] versatile: Push lsi initialization to the end List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: Peter Maydell , qemu-devel , Stefan Hajnoczi On 2012-10-08 18:28, Paolo Bonzini wrote: > Il 08/10/2012 18:02, Peter Maydell ha scritto: >>>> It's not (only) about a missing event for the serial frontend, it's also >>>> about a spurious open event to the monitor. That generates unwanted >>>> output during startup. >> Right, so whatever's sending that event needs not to do so until >> creation of the machine is complete. Sending events randomly >> halfway through init is a recipe for problems... > > So we now have proof that using bottom halves outside the block layer > was a bad idea. Thanks Jan. :) > > If Stefan goes on with the AioContext idea, we can have separate > AioContexts for qemu_bh_new on one side and for block devices on the > other, so that qemu_bh_new bottom halves won't fire just because > something is calling the block layer. > > In the meanwhile, qemu_char could use a QEMUTimer expiring in the past > instead of a bottom half. Sounds "beautiful", waiting to break when we leave like this and start playing with the timer subsystem ;). But I guess it's best for now. Let me have a look... Jan -- Siemens AG, Corporate Technology, CT RTC ITP SDP-DE Corporate Competence Center Embedded Linux