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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 B5BA7C433E0 for ; Wed, 17 Mar 2021 10:39:05 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 543FB64F01 for ; Wed, 17 Mar 2021 10:39:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 543FB64F01 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44396 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lMTZw-0003LQ-A9 for qemu-devel@archiver.kernel.org; Wed, 17 Mar 2021 06:39:04 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35846) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMTYi-0002ho-Av for qemu-devel@nongnu.org; Wed, 17 Mar 2021 06:37:48 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:40744) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lMTYg-0000GR-PF for qemu-devel@nongnu.org; Wed, 17 Mar 2021 06:37:48 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615977466; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=NXe/aI00IfjQ+oW9XAtpH0jcpcz9cqfW4moJoURMAFc=; b=OVPCkhFuvi7FfcTLOZgQJyVhsiWNugnPTsz6qPGUegMar5TbsIlhjHTZOhCGzojB4C7KlZ W9SHc8CHrKK5qKF+SvgkB2WatvursDqmSLAv6ACvWRn1YrsMLwjhdAlpBOnUmHYehZqU5p wcpvg6Xs5F3WnP3Ws863XnM9O0pe1CI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-225-UuuLZ4Q0PlqkCWSR6SqQHQ-1; Wed, 17 Mar 2021 06:37:44 -0400 X-MC-Unique: UuuLZ4Q0PlqkCWSR6SqQHQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A5C9C190A7A2; Wed, 17 Mar 2021 10:37:42 +0000 (UTC) Received: from [10.64.54.49] (vpn2-54-49.bne.redhat.com [10.64.54.49]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C4BC16C330; Wed, 17 Mar 2021 10:37:36 +0000 (UTC) Subject: Re: [PATCH] hw/char/pl011: Fix clock migration failure To: Peter Maydell References: <20210317044441.112313-1-gshan@redhat.com> From: Gavin Shan Message-ID: <73a30558-469e-8ef0-02b2-aaaaa2449cda@redhat.com> Date: Wed, 17 Mar 2021 21:37:32 +1100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.0 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=gshan@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=gshan@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -29 X-Spam_score: -3.0 X-Spam_bar: --- X-Spam_report: (-3.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.25, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Gavin Shan Cc: Luc Michel , QEMU Developers , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= , qemu-arm , Shan Gavin , Paolo Bonzini , =?UTF-8?Q?Marc-Andr=c3=a9_Lureau?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Hi Peter, On 3/17/21 8:09 PM, Peter Maydell wrote: > On Wed, 17 Mar 2021 at 04:44, Gavin Shan wrote: >> >> There is a added clock to trace buad rate change since v5.2.0 by >> commit aac63e0e6ea3 ("hw/char/pl011: add a clock input"). The added >> clock causes migration failure. For example, migration from v5.2.0 >> to v5.1.0 can fail with the following error messages: >> >> qemu-system-aarch64: error while loading state for instance 0x0 \ >> of device 'pl011' >> qemu-system-aarch64: load of migration failed: No such file or \ >> directory >> >> This fixes the issue by reporting the baud rate change at post load >> time so that the clock won't be migrated by sub-section to avoid the >> migration failure. >> >> Cc: qemu-stable@nongnu.org >> Fixes: aac63e0e6ea3 ("hw/char/pl011: add a clock input") >> Signed-off-by: Gavin Shan >> --- >> hw/char/pl011.c | 22 +++++++++------------- >> 1 file changed, 9 insertions(+), 13 deletions(-) >> >> diff --git a/hw/char/pl011.c b/hw/char/pl011.c >> index c5621a195f..401bd28536 100644 >> --- a/hw/char/pl011.c >> +++ b/hw/char/pl011.c >> @@ -322,20 +322,20 @@ static const MemoryRegionOps pl011_ops = { >> .endianness = DEVICE_NATIVE_ENDIAN, >> }; >> >> -static const VMStateDescription vmstate_pl011_clock = { >> - .name = "pl011/clock", >> - .version_id = 1, >> - .minimum_version_id = 1, >> - .fields = (VMStateField[]) { >> - VMSTATE_CLOCK(clk, PL011State), >> - VMSTATE_END_OF_LIST() >> - } >> -}; >> +static int pl011_post_load(void *opaque, int version_id) >> +{ >> + PL011State *s = PL011(opaque); >> + >> + pl011_trace_baudrate_change(s); >> + >> + return 0; >> +} >> >> static const VMStateDescription vmstate_pl011 = { >> .name = "pl011", >> .version_id = 2, >> .minimum_version_id = 2, >> + .post_load = pl011_post_load, >> .fields = (VMStateField[]) { >> VMSTATE_UINT32(readbuff, PL011State), >> VMSTATE_UINT32(flags, PL011State), >> @@ -355,10 +355,6 @@ static const VMStateDescription vmstate_pl011 = { >> VMSTATE_INT32(read_trigger, PL011State), >> VMSTATE_END_OF_LIST() >> }, >> - .subsections = (const VMStateDescription * []) { >> - &vmstate_pl011_clock, >> - NULL >> - } >> }; > > Doesn't dropping the subsection break migration compat ? > It's why this patch needs to be backported to stable branches. In that way, we won't have migration compatible issue. Thanks, Gavin