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 B095BC3600C for ; Tue, 8 Apr 2025 11:59:48 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u27bX-0000lU-Pu; Tue, 08 Apr 2025 07:58:59 -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 1u27bU-0000l6-4o for qemu-devel@nongnu.org; Tue, 08 Apr 2025 07:58:56 -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 1u27bR-0001h1-Bu for qemu-devel@nongnu.org; Tue, 08 Apr 2025 07:58:54 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744113531; h=from:from: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=2IMIUKH1VC1WHLNHlnHnpdMZ8XiechGzp7dOYcy6oZY=; b=hfW1otlwFHtbD37c8TovRmd/61cndHY8jZuRklrSgAeZLCxPnvM8U3zfH+q+gXUhtCT2xM 4IWGwztkfyHYZVtZ7dEA0Hw7s3T2u21dps5g4K7gFxpWUFHzGMdg7qLT2weFNTbsW92399 umZKbtFvPmWd/n9BkSwZvLsutHEGym0= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-472-Xt5UOaaSPF-WHKg49hx8BA-1; Tue, 08 Apr 2025 07:58:48 -0400 X-MC-Unique: Xt5UOaaSPF-WHKg49hx8BA-1 X-Mimecast-MFC-AGG-ID: Xt5UOaaSPF-WHKg49hx8BA_1744113527 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3B00C18009B1; Tue, 8 Apr 2025 11:58:46 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.7]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CF7B9195609D; Tue, 8 Apr 2025 11:58:45 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id DD75D21E6757; Tue, 08 Apr 2025 13:58:42 +0200 (CEST) From: Markus Armbruster To: Alex =?utf-8?Q?Benn=C3=A9e?= Cc: Mario Fleischmann , qemu-devel@nongnu.org, philmd@linaro.org, christian.boenig@lauterbach.com Subject: Re: [PATCH 00/16] Add Multi-Core Debug (MCD) API support In-Reply-To: <87a58qj3ay.fsf@draig.linaro.org> ("Alex =?utf-8?Q?Benn=C3=A9?= =?utf-8?Q?e=22's?= message of "Tue, 08 Apr 2025 12:33:25 +0100") References: <20250310150510.200607-1-mario.fleischmann@lauterbach.com> <87semkw3qx.fsf@pond.sub.org> <87semjp286.fsf@pond.sub.org> <0736943f-443b-4bfc-8d69-f30f42029d07@lauterbach.com> <87r023m422.fsf@pond.sub.org> <87a58qj3ay.fsf@draig.linaro.org> Date: Tue, 08 Apr 2025 13:58:42 +0200 Message-ID: <87ldsakgp9.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.845, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=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: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Alex Benn=C3=A9e writes: > Markus Armbruster writes: > >> Mario Fleischmann writes: >> >>> Apologies for the line wrapping in yesterday's answer. Should be fixed = now. >>> >>> On 08.04.2025 09:00, Markus Armbruster wrote: [...] >>>> What about providing the MCD interface as a separate QMP-like protocol? >>>> It gets its own QAPI schema, just like for qemu-ga. Simplifies >>>> compiling it out when not needed. >>>> >>>> It gets its own socket, just like the GDB stub. Might reduce >>>> interference between debugging and QMP. >>>>=20 >>>> Thoughts? Alex, Philippe, care to chime in? >>> >>> Sound reasonable to me. Keeping in mind the size of generated QAPI code, >>> an option to `./configure [...] --enable-mcd` is definitely advisable. >> >> Alex, Philippe? > > When I spoke to Mario at DVCon last year I liked the idea of re-using > QMP instead of inventing yet another RPC interface for QEMU. QMP > certainly has nicer properties than the gdbstub which has a very > "organic" and "serial" feel to it. > > Are you suggesting we re-use the machinery but use an entirely separate > socket with just the MCD namespace in it? I don't see that being a > problem as long as we can test it properly in the CI. Yes. "Keep them separate" is only a gut feeling, though. While I pay attention to my gut feelings, I know they can be wrong. I am soliciting opinions.