From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4491DEE14D0 for ; Wed, 6 Sep 2023 20:19:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244286AbjIFUTL (ORCPT ); Wed, 6 Sep 2023 16:19:11 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44322 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233587AbjIFUTJ (ORCPT ); Wed, 6 Sep 2023 16:19:09 -0400 Received: from torres.zugschlus.de (torres.zugschlus.de [IPv6:2a01:238:42bc:a101::2:100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4FE7919A3; Wed, 6 Sep 2023 13:19:02 -0700 (PDT) Received: from mh by torres.zugschlus.de with local (Exim 4.96) (envelope-from ) id 1qdyzG-006ZTz-1m; Wed, 06 Sep 2023 22:18:54 +0200 Date: Wed, 6 Sep 2023 22:18:54 +0200 From: Marc Haber To: Tony Lindgren Cc: Sean Christopherson , Bagas Sanjaya , linux-kernel@vger.kernel.org, Linux Regressions , Linux KVM , Paolo Bonzini Subject: Re: Linux 6.5 speed regression, boot VERY slow with anything systemd related Message-ID: References: <20230901122431.GU11676@atomide.com> <20230906152616.GE11676@atomide.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230906152616.GE11676@atomide.com> User-Agent: Mutt/2.2.9 (2022-11-12) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 06, 2023 at 06:26:16PM +0300, Tony Lindgren wrote: > * Marc Haber [230906 14:41]: > > With my tools I have found out that it really seems to be related to the > > CPU of the host. I have changed my VM definition to "copy host CPU > > configuration to VM" in libvirt and have moved this very VM (image and > > settings) to hosts with a "Ryzen 5 Pro 4650G" and to an "Intel Xeon > > E3-1246" where they work flawlessly, while on both APUs I have available > > ("AMD G-T40E" and "AMD GX-412TC SOC") the regression in 6.5 shows. And > > if I boot other VMs on the APUs with 6.5 the issue comes up. It is a > > clear regression since going back to 4.6's serial code solves the issue > > on the APUs. > > Not sure why the CPU matters here.. Neither am I. > One thing to check is if you have these in your .config: > > CONFIG_SERIAL_CORE=y > CONFIG_SERIAL_CORE_CONSOLE=y That's affirmative. Otherwise, I think that serial console wouldn't work at all, but I get early kernel messages just fine and even at normal speed. > Or do you maybe have CONFIG_SERIAL_CORE=m as loadable module? Negative. Greetings Marc -- ----------------------------------------------------------------------------- Marc Haber | "I don't trust Computers. They | Mailadresse im Header Leimen, Germany | lose things." Winona Ryder | Fon: *49 6224 1600402 Nordisch by Nature | How to make an American Quilt | Fax: *49 6224 1600421