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=-1.0 required=3.0 tests=DATE_IN_PAST_03_06, DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 E6413C31E40 for ; Mon, 12 Aug 2019 13:55:58 +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 B146920684 for ; Mon, 12 Aug 2019 13:55:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=gibson.dropbear.id.au header.i=@gibson.dropbear.id.au header.b="bBJGZ3/t" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B146920684 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=gibson.dropbear.id.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:45740 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hxAnl-00006A-W8 for qemu-devel@archiver.kernel.org; Mon, 12 Aug 2019 09:55:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57918) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hxAmS-0006fp-QZ for qemu-devel@nongnu.org; Mon, 12 Aug 2019 09:54:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hxAmR-00005K-Dg for qemu-devel@nongnu.org; Mon, 12 Aug 2019 09:54:36 -0400 Received: from bilbo.ozlabs.org ([2401:3900:2:1::2]:47087 helo=ozlabs.org) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hxAmL-0008Qd-C0; Mon, 12 Aug 2019 09:54:29 -0400 Received: by ozlabs.org (Postfix, from userid 1007) id 466cld5WCgz9sPL; Mon, 12 Aug 2019 23:54:21 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=gibson.dropbear.id.au; s=201602; t=1565618061; bh=WgEiA2bYSoYo1c+YVtUVqwKW3af/hSyQnnzpCRq/SrA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bBJGZ3/t7i/EZwLzbf4eb7ls2oRUoKmE+xRciukNM6aDtGvfoSuL0ijgw5h5kZwYi HrWkq8g4sEHrnXWxh/wtZ+XRZUz4IXug91xrFQC4fPf9KzcFmKB9L0QIQKiHCCFeSq yjLJuX0SRMoHxUZpFLLKIIBAI3A4TfAlEc2/vHD0= Date: Mon, 12 Aug 2019 20:36:33 +1000 From: David Gibson To: =?iso-8859-1?Q?C=E9dric?= Le Goater Message-ID: <20190812103633.GL3947@umbus.fritz.box> References: <20190729145654.14644-1-damien.hedde@greensocs.com> <20190729145654.14644-6-damien.hedde@greensocs.com> <20190731060533.GD2032@umbus.fritz.box> <51aa7e6d-3568-8485-4b67-a598a24a1f3d@greensocs.com> <20190808064810.GE5465@umbus.fritz.box> <4fa2ecbe-d81e-5285-822e-28f984aed77c@kaod.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="CgTrtGVSVGoxAIFj" Content-Disposition: inline In-Reply-To: <4fa2ecbe-d81e-5285-822e-28f984aed77c@kaod.org> User-Agent: Mutt/1.12.1 (2019-06-15) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2401:3900:2:1::2 Subject: Re: [Qemu-devel] [PATCH v3 05/33] Switch to new api in qdev/bus 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: , Cc: fam@euphon.net, peter.maydell@linaro.org, walling@linux.ibm.com, dmitry.fleytman@gmail.com, mst@redhat.com, mark.cave-ayland@ilande.co.uk, qemu-devel@nongnu.org, kraxel@redhat.com, edgar.iglesias@xilinx.com, hare@suse.com, qemu-block@nongnu.org, david@redhat.com, pasic@linux.ibm.com, borntraeger@de.ibm.com, marcandre.lureau@redhat.com, thuth@redhat.com, ehabkost@redhat.com, alistair@alistair23.me, qemu-s390x@nongnu.org, qemu-arm@nongnu.org, jsnow@redhat.com, rth@twiddle.net, Damien Hedde , berrange@redhat.com, cohuck@redhat.com, mark.burton@greensocs.com, qemu-ppc@nongnu.org, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" --CgTrtGVSVGoxAIFj Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Aug 09, 2019 at 01:39:46PM +0200, C=E9dric Le Goater wrote: >=20 > >>> So.. is this change in the device_reset() signature really necessary? > >>> Even if there are compelling reasons to handle warm reset in the new > >>> API, that doesn't been you need to change device_reset() itself from > >>> its established meaning of a cold (i.e. as per power cycle) reset. > >>> Warm resets are generally called in rather more specific circumstances > >>> (often under guest software direction) so it seems likely that users > >>> would want to engage with the new reset API directly. Or we could > >>> just create a device_warm_reset() wrapper. That would also avoid the > >>> bare boolean parameter, which is not great for readability (you have > >>> to look up the signature to have any idea what it means). > >> > >> I've added device_reset_cold/warm wrapper functions to avoid having to > >> pass the boolean parameter. it seems I forgot to use them in qdev.c > >> I suppose, like you said, we could live with > >> + no function with the boolean parameter > >> + device_reset doing cold reset > >> + device_reset_warm (or device_warm_reset) for the warm version > >=20 > > Ok, good. > >=20 > > I'm afraid the whole series still makes me pretty uncomfortable, > > though, since the whole "warm reset" concept still seems way to vague > > to me. >=20 > Isn't the reset after the CAS negotiation sequence between the hypervisor > and the pseries machine some sort of warm reset driven by SW ? Yes.. and? The fact that something as messy as CAS can come under the category of warm reset only re-inforces that what a warm reset is isn't really well defined. [That said, in the case of CAS, I'd really like it if we can change things to avoid the pseudo-reset and just rewrite the dt instead. The sorta-reboot causes us problems with -no-reboot and with disabling the SLOF autoboot flag] --=20 David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson --CgTrtGVSVGoxAIFj Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEEdfRlhq5hpmzETofcbDjKyiDZs5IFAl1RQTEACgkQbDjKyiDZ s5KUyxAAu2TiBsf0j9fE+XbZL0oHDdf3cZwxK+R8IIX+KPxmoWrx3uWJ0eYKKj2y K2hO9fJQvJPxfs615SuVOy684MkEGldNyItKe/2kVaBS78H17hTFQDKmEVp9uZgx gO5Z1CcBeVRcPTqUvSBn87ZpaehcmD0ZZDacFus3giMeReQz/nbhH78sAnLmrPdY Yblmeq/7+kSbMhFtSh7g7tPtoK4OepkNfhVTWogeX9TymuGsS5+NiQZUPPNlCxnC JtLlhLskFe24JMA5rt8IC/E6KPEvwr6ieR0Hdk4PeGBeI4BfqlZzAwcOrVyuy0x4 C3aQtq6XuVyKLAXdENyb5C+tY7r6Yo/ZwjOpC/byFprsCN/E0qamx1RU6uaadvIz zTgzYKVpwY7H/hmVQgWUzD2ucJ6tv3umN5/cqc4CFurfEOuKw/3+ypN0hsT9P0ro QJfv//NsrpbXZ5yqebszEfla9bxVMR8Zk/osMIvtpdx+2XKezRh8C75K82umpwwy bTd1oibYJ8dsOK644hjb9f7ctWz9CuLa+H1moS40VZa49ny1gW6wW8E1euUCFwdH n1J+uHkNHT4/ifrLN00kIFV/t7CNHk9HuXjFE5etWnQcAKlQjWpDjwpbxUGI1w5Y U/m1uRsXBPgA72cGHp1DJvdAaeZ0outw4GjbFE+QM1nd16izQG8= =56Xh -----END PGP SIGNATURE----- --CgTrtGVSVGoxAIFj--