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 X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8B6A5C43144 for ; Mon, 25 Jun 2018 08:05:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4E1B62559A for ; Mon, 25 Jun 2018 08:05:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4E1B62559A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753182AbeFYIF4 (ORCPT ); Mon, 25 Jun 2018 04:05:56 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:58464 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752589AbeFYIFy (ORCPT ); Mon, 25 Jun 2018 04:05:54 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7B3548315E; Mon, 25 Jun 2018 08:05:53 +0000 (UTC) Received: from gondolin (dhcp-192-215.str.redhat.com [10.33.192.215]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7790411166E2; Mon, 25 Jun 2018 08:05:51 +0000 (UTC) Date: Mon, 25 Jun 2018 10:05:48 +0200 From: Cornelia Huck To: Christian Borntraeger Cc: Guenter Roeck , Martin Schwidefsky , Vasily Gorbik , Heiko Carstens , linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, qemu-s390x , qemu-devel , Thomas Huth Subject: Re: s390 qemu boot failure in -next Message-ID: <20180625100548.64222dad.cohuck@redhat.com> In-Reply-To: <88d9afed-f91d-c320-13c8-9a93fc52b700@de.ibm.com> References: <20180622194736.GA5794@roeck-us.net> <126ac556-0602-b927-58f5-cb5f65a5e0ec@de.ibm.com> <88d9afed-f91d-c320-13c8-9a93fc52b700@de.ibm.com> Organization: Red Hat GmbH MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 25 Jun 2018 08:05:53 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.1]); Mon, 25 Jun 2018 08:05:53 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'cohuck@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 25 Jun 2018 09:27:59 +0200 Christian Borntraeger wrote: > Also adding QEMU. > > On 06/25/2018 09:10 AM, Christian Borntraeger wrote: > > > > > > On 06/22/2018 09:47 PM, Guenter Roeck wrote: > >> Hi, > >> > >> starting with commit 's390/boot: make head.S and als.c be part of the > >> decompressor only' in -next, s390 immages no longer boot in qemu. > >> As far as I can see, the reason is that the command line is no longer > >> passed from qemu to the kernel, which results in a panic because the > >> root file system can not be mounted. > >> > >> Was this change made on purpose ? If so, is there a way to get qemu > >> back to working ? > > > > Certainly not on purpose. > > > > Vasily, I can reproduce this with KVM and an external kernel boot of the vmlinux file (the elf file) > > > > e.g. > > > > qemu-system-s390 -enable-kvm -nographic -kernel vmlinux -append "this string no longer is command line" > > > > The compressed image (bzImage) seems to work fine though. > > > > This seems to be an unfortunate side effect of QEMUs ways to "guess" its Linux (checking for start > > address 0x10000, which is no longer true for the vmlinux file). With the pure vmlinux elf file > > the load address is 0x100000 as there is no unpacker. Do we consider these locations to be an exported interface, or is it just QEMU guessing? > > > > Guenter, can you check if arch/s390/boot/bzImage works for you as a workaround? > > Something like this in QEMU > > diff --git a/hw/s390x/ipl.c b/hw/s390x/ipl.c > index f278036fa7..14153ce880 100644 > --- a/hw/s390x/ipl.c > +++ b/hw/s390x/ipl.c > @@ -187,11 +187,13 @@ static void s390_ipl_realize(DeviceState *dev, Error **errp) > */ > if (pentry == KERN_IMAGE_START || pentry == 0x800) { > ipl->start_addr = KERN_IMAGE_START; > - /* Overwrite parameters in the kernel image, which are "rom" */ > - strcpy(rom_ptr(KERN_PARM_AREA), ipl->cmdline); > } else { > ipl->start_addr = pentry; > } > + if (ipl->cmdline) { > + /* If there is a command line, put it in the right place */ > + strcpy(rom_ptr(KERN_PARM_AREA), ipl->cmdline); > + } Check for the magic Linux string (like in the non-elf case) first? > > if (ipl->initrd) { > ram_addr_t initrd_offset; > > would put the command line in no matter what the start address is. I'm for putting that one in (and backporting it to qemu-stable). It's a bit worrying, though, that our ipl code is so fragile...