From patchwork Mon Dec 14 10:05:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kurz X-Patchwork-Id: 11971731 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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 62F7CC4361B for ; Mon, 14 Dec 2020 10:09:17 +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 88E25225A9 for ; Mon, 14 Dec 2020 10:09:16 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 88E25225A9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kaod.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52974 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kokn5-0007YM-E1 for qemu-devel@archiver.kernel.org; Mon, 14 Dec 2020 05:09:15 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:36552) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kokk7-0004Qo-Pd for qemu-devel@nongnu.org; Mon, 14 Dec 2020 05:06:11 -0500 Received: from us-smtp-delivery-44.mimecast.com ([207.211.30.44]:22887) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kokk3-0006vE-I3 for qemu-devel@nongnu.org; Mon, 14 Dec 2020 05:06:11 -0500 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-279-jOogFDbZNR-yYZPVccP1cw-1; Mon, 14 Dec 2020 05:05:54 -0500 X-MC-Unique: jOogFDbZNR-yYZPVccP1cw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BB303800D55; Mon, 14 Dec 2020 10:05:52 +0000 (UTC) Received: from bahia.lan (ovpn-114-254.ams2.redhat.com [10.36.114.254]) by smtp.corp.redhat.com (Postfix) with ESMTP id 7EE8971CB4; Mon, 14 Dec 2020 10:05:51 +0000 (UTC) Subject: [PATCH REPOST] spapr: Allow memory unplug to always succeed From: Greg Kurz To: qemu-devel@nongnu.org Date: Mon, 14 Dec 2020 11:05:50 +0100 Message-ID: <160794035064.23292.17560963281911312439.stgit@bahia.lan> User-Agent: StGit/0.21 MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: kaod.org Received-SPF: softfail client-ip=207.211.30.44; envelope-from=groug@kaod.org; helo=us-smtp-delivery-44.mimecast.com X-Spam_score_int: -11 X-Spam_score: -1.2 X-Spam_bar: - X-Spam_report: (-1.2 / 5.0 requ) BAYES_00=-1.9, SPF_HELO_NONE=0.001, SPF_SOFTFAIL=0.665 autolearn=no 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: , Cc: qemu-ppc@nongnu.org, Greg Kurz , David Gibson Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" It is currently impossible to hot-unplug a memory device between machine reset and CAS. (qemu) device_del dimm1 Error: Memory hot unplug not supported for this guest This limitation was introduced in order to provide an explicit error path for older guests that didn't support hot-plug event sources (and thus memory hot-unplug). The linux kernel has been supporting these since 4.11. All recent enough guests are thus capable of handling the removal of a memory device at all time, including during early boot. Lift the limitation for the latest machine type. This means that trying to unplug memory from a guest that doesn't support it will likely just do nothing and the memory will only get removed at next reboot. Such older guests can still get the existing behavior by using an older machine type. Signed-off-by: Greg Kurz --- This patch was initially posted before the compat machine types for 6.0 got merged upstream. During the same period, David was also transitioning from github to gitlab, and the patch didn't applied cleanly. Now it does. Just reposting it unchanged for convenience. --- hw/ppc/spapr.c | 6 +++++- hw/ppc/spapr_events.c | 3 ++- include/hw/ppc/spapr.h | 1 + 3 files changed, 8 insertions(+), 2 deletions(-) diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c index dee48a0043bb..481c800a5a33 100644 --- a/hw/ppc/spapr.c +++ b/hw/ppc/spapr.c @@ -4051,7 +4051,8 @@ static void spapr_machine_device_unplug_request(HotplugHandler *hotplug_dev, SpaprMachineClass *smc = SPAPR_MACHINE_CLASS(mc); if (object_dynamic_cast(OBJECT(dev), TYPE_PC_DIMM)) { - if (spapr_ovec_test(sms->ov5_cas, OV5_HP_EVT)) { + if (!smc->pre_6_0_memory_unplug || + spapr_ovec_test(sms->ov5_cas, OV5_HP_EVT)) { spapr_memory_unplug_request(hotplug_dev, dev, errp); } else { /* NOTE: this means there is a window after guest reset, prior to @@ -4537,8 +4538,11 @@ DEFINE_SPAPR_MACHINE(6_0, "6.0", true); */ static void spapr_machine_5_2_class_options(MachineClass *mc) { + SpaprMachineClass *smc = SPAPR_MACHINE_CLASS(mc); + spapr_machine_6_0_class_options(mc); compat_props_add(mc->compat_props, hw_compat_5_2, hw_compat_5_2_len); + smc->pre_6_0_memory_unplug = true; } DEFINE_SPAPR_MACHINE(5_2, "5.2", false); diff --git a/hw/ppc/spapr_events.c b/hw/ppc/spapr_events.c index 3f37b49fd8ad..6aedd988b3d0 100644 --- a/hw/ppc/spapr_events.c +++ b/hw/ppc/spapr_events.c @@ -658,7 +658,8 @@ static void spapr_hotplug_req_event(uint8_t hp_id, uint8_t hp_action, /* we should not be using count_indexed value unless the guest * supports dedicated hotplug event source */ - g_assert(spapr_ovec_test(spapr->ov5_cas, OV5_HP_EVT)); + g_assert(!SPAPR_MACHINE_GET_CLASS(spapr)->pre_6_0_memory_unplug || + spapr_ovec_test(spapr->ov5_cas, OV5_HP_EVT)); hp->drc_id.count_indexed.count = cpu_to_be32(drc_id->count_indexed.count); hp->drc_id.count_indexed.index = diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h index e0f10f252c08..06a5b4259f20 100644 --- a/include/hw/ppc/spapr.h +++ b/include/hw/ppc/spapr.h @@ -139,6 +139,7 @@ struct SpaprMachineClass { hwaddr rma_limit; /* clamp the RMA to this size */ bool pre_5_1_assoc_refpoints; bool pre_5_2_numa_associativity; + bool pre_6_0_memory_unplug; bool (*phb_placement)(SpaprMachineState *spapr, uint32_t index, uint64_t *buid, hwaddr *pio,