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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CBFB8C433FE for ; Wed, 10 Nov 2021 15:27:35 +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 2A8896103A for ; Wed, 10 Nov 2021 15:27:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 2A8896103A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:41432 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mkpVe-0000OC-7K for qemu-devel@archiver.kernel.org; Wed, 10 Nov 2021 10:27:34 -0500 Received: from eggs.gnu.org ([209.51.188.92]:38312) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mkpU8-0007iz-Om for qemu-devel@nongnu.org; Wed, 10 Nov 2021 10:26:01 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:30040) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mkpU5-0004WR-AO for qemu-devel@nongnu.org; Wed, 10 Nov 2021 10:25:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1636557956; 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: in-reply-to:in-reply-to:references:references; bh=zN6Q2dIzPyQXOgBHquEJ+ixG2wGCctiCvyXRCyputow=; b=NdPZquBchFfru5KkSGuccuFF3ej3+Aw1GAC1DG12cJOnEacmfngHdPIbzMQgq+DgxhBstA HYnot4h6/7vVJh7DtOhR68E3D0POFSJOjQEsBuLGHRrLPiOWqCWbZX5jC8OkY1h+hVS4zZ wXUI8rau10oEzBS8H2i2G6c79wDvC50= Received: from mail-oo1-f72.google.com (mail-oo1-f72.google.com [209.85.161.72]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-363-ri9l2xeDOyWGP0bGdQ8Tiw-1; Wed, 10 Nov 2021 10:25:53 -0500 X-MC-Unique: ri9l2xeDOyWGP0bGdQ8Tiw-1 Received: by mail-oo1-f72.google.com with SMTP id r22-20020a4ad4d6000000b002bb8cc2ea41so1308928oos.4 for ; Wed, 10 Nov 2021 07:25:52 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=zN6Q2dIzPyQXOgBHquEJ+ixG2wGCctiCvyXRCyputow=; b=FqeG2ArAvfY5ByCpSSXT9iPjx+U5IAkKVLvjqBhDOE8L1HQENw1F06cifOZlyPkpM+ 0Ryn0mufVBBOP77w/kKGp1RtBnN+KIk2tNsDli9WPk0Jmh+PmWPk3QYE3c4ag/k6yzuv 7Rcl6bXD8ikq9YLGeXmrCQKkliP8484t5EaprlbG4lmYM9tCUgk+n4XLXAhjBXa1+Trs wvDiobWaPpMVw8fT6qazNF3M+v0ExxlMqFHxTxkZegb5n6Y+EBVk4rZ7d0375Yr22RrO r6eCiEXmV9VKH1A1iaFAG0h7DthS5YvUw5WTFhieumORWF6PrRMVShrxAoAkpRsz0t1a 2A4g== X-Gm-Message-State: AOAM532eywg+kT/OZ6V892l7S2egSvU60nMuI5ya8OC44fLI0CeZzLBW vMKIaCtgf3EVI6LkQvnM6sTpqAqpQxrnD/tlan75ezG9R5yzL8mgGcpTKU6p8EMv9Wn10BzFkEO sbOFL46gRyOfe9EVwWk9h36Yp27hmMvI= X-Received: by 2002:a05:6830:19c5:: with SMTP id p5mr49466otp.195.1636557952250; Wed, 10 Nov 2021 07:25:52 -0800 (PST) X-Google-Smtp-Source: ABdhPJyuzfaydRdKn0DYubZH7NymDYxfZZAqmlFPbqC2fqBDPxl51nPjRB0bSp4vyPCLZVPN7GBcaY6Py66uCxR8aaY= X-Received: by 2002:a05:6830:19c5:: with SMTP id p5mr49429otp.195.1636557951761; Wed, 10 Nov 2021 07:25:51 -0800 (PST) MIME-Version: 1.0 References: <20211110053014.489591-1-jusual@redhat.com> <20211110053014.489591-5-jusual@redhat.com> <20211110011557-mutt-send-email-mst@kernel.org> <20211110145759.6570170e@redhat.com> In-Reply-To: <20211110145759.6570170e@redhat.com> From: Julia Suvorova Date: Wed, 10 Nov 2021 16:25:40 +0100 Message-ID: Subject: Re: [PATCH 4/5] hw/i386/acpi-build: Deny control on PCIe Native Hot-plug in _OSC To: Igor Mammedov Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=jsuvorov@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Received-SPF: pass client-ip=170.10.129.124; envelope-from=jsuvorov@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=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: , Cc: Ani Sinha , Marcel Apfelbaum , Gerd Hoffmann , QEMU Developers , "Michael S. Tsirkin" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Nov 10, 2021 at 2:58 PM Igor Mammedov wrote: > > On Wed, 10 Nov 2021 02:21:34 -0500 > "Michael S. Tsirkin" wrote: > > > On Wed, Nov 10, 2021 at 06:30:13AM +0100, Julia Suvorova wrote: > > > There are two ways to enable ACPI PCI Hot-plug: > > > > > > * Disable the Hot-plug Capable bit on PCIe slots. > > > > > > This was the first approach which led to regression [1-2], as > > > I/O space for a port is allocated only when it is hot-pluggable, > > > which is determined by HPC bit. > > > > > > * Leave the HPC bit on and disable PCIe Native Hot-plug in _OSC > > > method. > > > > > > This removes the (future) ability of hot-plugging switches with PCIe > > > Native hotplug since ACPI PCI Hot-plug only works with cold-plugged > > > bridges. If the user wants to explicitely use this feature, they can > > > disable ACPI PCI Hot-plug with: > > > --global ICH9-LPC.acpi-pci-hotplug-with-bridge-support=off > > > > > > Change the bit in _OSC method so that the OS selects ACPI PCI Hot-plug > > > instead of PCIe Native. > > > > > > [1] https://gitlab.com/qemu-project/qemu/-/issues/641 > > > [2] https://bugzilla.redhat.com/show_bug.cgi?id=2006409 > > > > > > Signed-off-by: Julia Suvorova > > > --- > > > hw/i386/acpi-build.c | 12 ++++++++---- > > > 1 file changed, 8 insertions(+), 4 deletions(-) > > > > > > diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c > > > index a3ad6abd33..a2f92ab32b 100644 > > > --- a/hw/i386/acpi-build.c > > > +++ b/hw/i386/acpi-build.c > > > @@ -1337,7 +1337,7 @@ static void build_x86_acpi_pci_hotplug(Aml *table, uint64_t pcihp_addr) > > > aml_append(table, scope); > > > } > > > > > > -static Aml *build_q35_osc_method(void) > > > +static Aml *build_q35_osc_method(bool acpi_pcihp) > > > { > > > Aml *if_ctx; > > > Aml *if_ctx2; > > > @@ -1345,6 +1345,7 @@ static Aml *build_q35_osc_method(void) > > > Aml *method; > > > Aml *a_cwd1 = aml_name("CDW1"); > > > Aml *a_ctrl = aml_local(0); > > > + const uint64_t hotplug = acpi_pcihp ? 0x1E : 0x1F; > > > > drop this variable and open-code at use point below. > > As it is the comment is misplaced. > > Also a slightly better way to write this: > > 0x1E | (acpi_pcihp ? 0x0 : 0x1) > > > > > > > > > > > > method = aml_method("_OSC", 4, AML_NOTSERIALIZED); > > > aml_append(method, aml_create_dword_field(aml_arg(3), aml_int(0), "CDW1")); > > > > So what acpi_pcihp does is enable/disable native pcie hotplug. > > How about we call the option exactly that? > > > > > > > @@ -1359,8 +1360,9 @@ static Aml *build_q35_osc_method(void) > > > /* > > > * Always allow native PME, AER (no dependencies) > > > * Allow SHPC (PCI bridges can have SHPC controller) > > > + * Disable PCIe Native Hot-plug if ACPI PCI Hot-plug is enabled. > > > */ > > > - aml_append(if_ctx, aml_and(a_ctrl, aml_int(0x1F), a_ctrl)); > > > + aml_append(if_ctx, aml_and(a_ctrl, aml_int(hotplug), a_ctrl)); > > > > > > > using the variable hotplug just made things confusing, > > open-coding will be clearer. > > > > > > > if_ctx2 = aml_if(aml_lnot(aml_equal(aml_arg(1), aml_int(1)))); > > > /* Unknown revision */ > > > @@ -1449,7 +1451,7 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, > > > aml_append(dev, aml_name_decl("_CID", aml_eisaid("PNP0A03"))); > > > aml_append(dev, aml_name_decl("_ADR", aml_int(0))); > > > aml_append(dev, aml_name_decl("_UID", aml_int(pcmc->pci_root_uid))); > > > - aml_append(dev, build_q35_osc_method()); > > > + aml_append(dev, build_q35_osc_method(pm->pcihp_bridge_en)); > > > aml_append(sb_scope, dev); > > > if (mcfg_valid) { > > > aml_append(sb_scope, build_q35_dram_controller(&mcfg)); > > > > One of the complaints of libvirt people was that the > > name is confusing. It seems to say whether to describe bridges > > in ACPI but it also disables native hotplug, but only for PCIe. > > > > Maybe we should address this with flags saying whether to enable each of > > acpi,pcie,shpc hotplug separately... > > yep, mask with field defines would be better, > but I'd hold off such change to post 6.2 time. > > > > > > @@ -1565,7 +1567,9 @@ build_dsdt(GArray *table_data, BIOSLinker *linker, > > > if (pci_bus_is_express(bus)) { > > > aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A08"))); > > > aml_append(dev, aml_name_decl("_CID", aml_eisaid("PNP0A03"))); > > > - aml_append(dev, build_q35_osc_method()); > > > > > + /* Expander bridges do not have ACPI PCI Hot-plug enabled */ > > > + aml_append(dev, build_q35_osc_method(false)); > > this's it not obvious, why PXBs aren't capable of ACPI PCI Hot-plug? Lack of support from the original patchset. > > > } else { > > > aml_append(dev, aml_name_decl("_HID", aml_eisaid("PNP0A03"))); > > > } > > > -- > > > 2.31.1 > > >