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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id DEF8EC46CA1 for ; Mon, 18 Sep 2023 12:09:09 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qiD3E-0005oR-0R; Mon, 18 Sep 2023 08:08:28 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qiD3A-0005oE-OW for qemu-devel@nongnu.org; Mon, 18 Sep 2023 08:08:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qiD37-0001A3-JL for qemu-devel@nongnu.org; Mon, 18 Sep 2023 08:08:24 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1695038899; 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:in-reply-to:in-reply-to: references:references; bh=GcjX/yqa0XsH/V2A0bXbw5v8EYCuR0cJVt9GrD+omTw=; b=GJGCvDAojvqcKmCUmjrD0PwFFZScnWhgbv2maWk/gluai7K3t3TylANjUm/+ZtfDJ21i5Y 5AfHz5/36QLsmO65FcezxQZ7wfhl+oMDrU/C8HXMDIKqca1MFEifFvyi9xOPC7if45E1uo DjWMI2rUp5wFZrfpmuT+1RjezHDxy6A= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-540-70VGz_asMWK7KFLCNAXW0g-1; Mon, 18 Sep 2023 08:08:14 -0400 X-MC-Unique: 70VGz_asMWK7KFLCNAXW0g-1 Received: from smtp.corp.redhat.com (int-mx10.intmail.prod.int.rdu2.redhat.com [10.11.54.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id B13DE85A5BD; Mon, 18 Sep 2023 12:08:13 +0000 (UTC) Received: from redhat.com (unknown [10.42.28.114]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B4AEE492B05; Mon, 18 Sep 2023 12:08:12 +0000 (UTC) Date: Mon, 18 Sep 2023 13:08:10 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Stephen Brennan Cc: qemu-devel@nongnu.org, linux-debuggers@vger.kernel.org, =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Omar Sandoval , Thomas Huth Subject: Re: [PATCH v2 qemu 3/3] dump: Add qmp argument "reassembled" Message-ID: References: <20230914010315.945705-1-stephen.s.brennan@oracle.com> <20230914010315.945705-4-stephen.s.brennan@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20230914010315.945705-4-stephen.s.brennan@oracle.com> User-Agent: Mutt/2.2.9 (2022-11-12) X-Scanned-By: MIMEDefang 3.1 on 10.11.54.10 Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, Sep 13, 2023 at 06:03:15PM -0700, Stephen Brennan wrote: > This can be used from QMP command line as "-R" to mirror the > corresponding flag for makedumpfile. This enables the kdump_reassembled > flag introduced in the previous patch. > > Signed-off-by: Stephen Brennan > --- > dump/dump-hmp-cmds.c | 8 +++++++- > dump/dump.c | 12 +++++++++++- > hmp-commands.hx | 7 +++++-- > qapi/dump.json | 14 +++++++++++++- > 4 files changed, 36 insertions(+), 5 deletions(-) > diff --git a/qapi/dump.json b/qapi/dump.json > index 4ae1f722a9..9cc7c3ea93 100644 > --- a/qapi/dump.json > +++ b/qapi/dump.json > @@ -69,6 +69,18 @@ > # to dump all guest's memory, please specify the start @begin and > # @length > # > +# @reassembled: if false (the default), the kdump output formats will use the > +# "makedumpfile flattened" variant of the format, which is less broadly > +# compatible with analysis tools. The flattened dump can be reassembled > +# after the fact using the command "makedumpfile -R". If true, Qemu > +# attempts to generate the standard kdump format. This requires a > +# seekable file as output -- if the output file is not seekable, then > +# the flattened format is still generated. The standard format is more > +# broadly compatible with debugging tools, but generating it requires a > +# seekable output file descriptor, and could use more system memory due > +# to page cache utilization. This should be left unspecified for non-kdump > +# output formats. > +# > # @format: if specified, the format of guest memory dump. But non-elf > # format is conflict with paging and filter, ie. @paging, @begin > # and @length is not allowed to be specified with non-elf @format > @@ -89,7 +101,7 @@ > { 'command': 'dump-guest-memory', > 'data': { 'paging': 'bool', 'protocol': 'str', '*detach': 'bool', > '*begin': 'int', '*length': 'int', > - '*format': 'DumpGuestMemoryFormat'} } > + '*reassembled': 'bool', '*format': 'DumpGuestMemoryFormat'} } The 'reassembled' flag is changing the meaning of 3 out of the 5 'format' enum values. IMHO, we should just be adding new formats instead of changing the meaning of existing formats. It is a shame we have the current 'kdump' naming prefix, but we're stuck with that for backwards compat, we need a new prefix. I'd suggest 'kdump-raw'. eg # # @DumpGuestMemoryFormat: # # An enumeration of guest-memory-dump's format. # # @elf: elf format # # @kdump-zlib: makedumpfile flattened, kdump-compressed format with zlib-compressed # # @kdump-lzo: makedumpfile flattened, kdump-compressed format with lzo-compressed # # @kdump-snappy: makedumpfile flattened, kdump-compressed format with snappy-compressed # # @kdump-raw-zlib: raw assembled kdump-compressed format with zlib-compressed (since 8.2) # # @kdump-raw-lzo: raw assembled kdump-compressed format with lzo-compressed (since 8.2) # # @kdump-raw-snappy: raw assembled kdump-compressed format with snappy-compressed (since 8.2) # # @win-dmp: Windows full crashdump format, can be used instead of ELF # converting (since 2.13) # # Since: 2.0 ## { 'enum': 'DumpGuestMemoryFormat', 'data': [ 'elf', 'kdump-zlib', 'kdump-lzo', 'kdump-snappy', 'kdump-raw-zlib', 'kdump-raw-lzo', 'kdump-raw-snappy', 'win-dmp' ] } With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|