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=-6.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS 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 20C37C433E0 for ; Thu, 4 Jun 2020 10:59:06 +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 D65BA2075B for ; Thu, 4 Jun 2020 10:59:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="YvEtvVhp" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D65BA2075B 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]:57944 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jgnaT-0006Os-4R for qemu-devel@archiver.kernel.org; Thu, 04 Jun 2020 06:59:05 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:39574) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jgnZb-0005rp-IH for qemu-devel@nongnu.org; Thu, 04 Jun 2020 06:58:11 -0400 Received: from us-smtp-1.mimecast.com ([205.139.110.61]:52738 helo=us-smtp-delivery-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1jgnZa-0003Kc-OG for qemu-devel@nongnu.org; Thu, 04 Jun 2020 06:58:11 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1591268290; 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=x61v8BL2rn2n2NvMG5XCrSCx80JZbq2ZYsYCyAZBfTY=; b=YvEtvVhp6N6ILydm6aQaBSOHm9Te6qc9/4p4+s9lEw08UtFEZtygb8I3wBKf2eba1xWnw3 HWkVTvPvRN0252R5GET1Jsb3o8b/2sTeo5ES6o45Syn3roX+WVjchFORxcf+DA7/MveI4R icSbo0viVlZenSCXI0aYxPt7RTuooZU= 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-70-Zt5yf4k6P1CegT4HMYCyNA-1; Thu, 04 Jun 2020 06:58:08 -0400 X-MC-Unique: Zt5yf4k6P1CegT4HMYCyNA-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 9E8B91800D42 for ; Thu, 4 Jun 2020 10:58:07 +0000 (UTC) Received: from localhost (unknown [10.40.208.51]) by smtp.corp.redhat.com (Postfix) with ESMTP id 037AF5C48E; Thu, 4 Jun 2020 10:57:59 +0000 (UTC) Date: Thu, 4 Jun 2020 12:57:55 +0200 From: Igor Mammedov To: Julia Suvorova Subject: Re: [PATCH] hw/pci/pcie: Move hot plug capability check to pre_plug callback Message-ID: <20200604125755.12944ac4@redhat.com> In-Reply-To: <20200601162934.842648-1-jusual@redhat.com> References: <20200601162934.842648-1-jusual@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=205.139.110.61; envelope-from=imammedo@redhat.com; helo=us-smtp-delivery-1.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/06/04 01:08:38 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] 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_H2=-0.001, SPF_PASS=-0.001 autolearn=_AUTOLEARN 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: "Michael S. Tsirkin" , qemu-devel@nongnu.org, Markus Armbruster Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Mon, 1 Jun 2020 18:29:34 +0200 Julia Suvorova wrote: > Check for hot plug capability earlier to avoid removing devices attached > during the initialization process. > > Run qemu with an unattached drive: > -drive file=$FILE,if=none,id=drive0 \ > -device pcie-root-port,id=rp0,slot=3,bus=pcie.0,hotplug=off > Hotplug a block device: > device_add virtio-blk-pci,id=blk0,drive=drive0,bus=rp0 > If hotplug fails on plug_cb, drive0 will be deleted. > > Signed-off-by: Julia Suvorova > --- > Hard to say if it's a bug or generally acceptable behaviour, but seems like > hotplug_handler_plug should never fail. _unplug shouldn't fail the rest are allowed to, but it's hard to unwind intialization cleanly to _plug stage so if it's possible to do checks at _pre_plug time (i.e. before device's realize() is called) we should do so. Acked-by: Igor Mammedov > > hw/pci/pcie.c | 19 +++++++++++-------- > 1 file changed, 11 insertions(+), 8 deletions(-) > > diff --git a/hw/pci/pcie.c b/hw/pci/pcie.c > index f50e10b8fb..5b9c022d91 100644 > --- a/hw/pci/pcie.c > +++ b/hw/pci/pcie.c > @@ -407,6 +407,17 @@ static void pcie_cap_slot_plug_common(PCIDevice *hotplug_dev, DeviceState *dev, > void pcie_cap_slot_pre_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, > Error **errp) > { > + PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev); > + uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap; > + uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP); > + > + /* Check if hot-plug is disabled on the slot */ > + if (dev->hotplugged && (sltcap & PCI_EXP_SLTCAP_HPC) == 0) { > + error_setg(errp, "Hot-plug failed: unsupported by the port device '%s'", > + DEVICE(hotplug_pdev)->id); > + return; > + } > + > pcie_cap_slot_plug_common(PCI_DEVICE(hotplug_dev), dev, errp); > } > > @@ -415,7 +426,6 @@ void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, > { > PCIDevice *hotplug_pdev = PCI_DEVICE(hotplug_dev); > uint8_t *exp_cap = hotplug_pdev->config + hotplug_pdev->exp.exp_cap; > - uint32_t sltcap = pci_get_word(exp_cap + PCI_EXP_SLTCAP); > PCIDevice *pci_dev = PCI_DEVICE(dev); > > /* Don't send event when device is enabled during qemu machine creation: > @@ -431,13 +441,6 @@ void pcie_cap_slot_plug_cb(HotplugHandler *hotplug_dev, DeviceState *dev, > return; > } > > - /* Check if hot-plug is disabled on the slot */ > - if ((sltcap & PCI_EXP_SLTCAP_HPC) == 0) { > - error_setg(errp, "Hot-plug failed: unsupported by the port device '%s'", > - DEVICE(hotplug_pdev)->id); > - return; > - } > - > /* To enable multifunction hot-plug, we just ensure the function > * 0 added last. When function 0 is added, we set the sltsta and > * inform OS via event notification.