From patchwork Fri Aug 21 16:54:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ani Sinha X-Patchwork-Id: 11729991 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 97F4614F6 for ; Fri, 21 Aug 2020 16:54:43 +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 6B34920738 for ; Fri, 21 Aug 2020 16:54:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=anisinha-ca.20150623.gappssmtp.com header.i=@anisinha-ca.20150623.gappssmtp.com header.b="ClF6DJRI" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6B34920738 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=anisinha.ca Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Received: from localhost ([::1]:60932 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k9AJO-00086r-Nh for patchwork-qemu-devel@patchwork.kernel.org; Fri, 21 Aug 2020 12:54:42 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45010) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k9AIy-0007ft-Mv for qemu-devel@nongnu.org; Fri, 21 Aug 2020 12:54:16 -0400 Received: from mail-pl1-x643.google.com ([2607:f8b0:4864:20::643]:41999) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1k9AIw-0003kw-GX for qemu-devel@nongnu.org; Fri, 21 Aug 2020 12:54:16 -0400 Received: by mail-pl1-x643.google.com with SMTP id f5so1131492plr.9 for ; Fri, 21 Aug 2020 09:54:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=anisinha-ca.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id; bh=14wpluU6NR6qwHDAbZG/4NWjd1z9J0dR1pJdUmBacr0=; b=ClF6DJRI92wTejCQWtSoWzI8Uhz/6Zn4YP2XdQXq3T2e1fxNi1obHkdxHYSVI2URUO z1TvXtIgDhGC5uGGTmNhEhdmmReizEiwxgPigAe/o/dXWq6f/QyORYvo/Ce6fNSoK1xU waM3PBBcfG4ljkVezVIMRaRQH0q0B/JOeLVpHVzXY1At1tnL38749HjzoUE/Y5Lduw3e QH0/01YjQuwoSkQj3sdZhm2tMEFq40YU+41p+RbCo7YkAT9ksi92rRfytQns1ozKG3Nu svyBDeo1pmpzfCkrgVU10CGjESGk1B9onGbR3g9cVJXdM+rY7b3zCtg5m11lojPVFE54 YIWQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=14wpluU6NR6qwHDAbZG/4NWjd1z9J0dR1pJdUmBacr0=; b=PTar7Yt0LdzLiyaghrytJznELTZKcKqhn7c1J9U9D93uvbFj3l/Al2Dy1Uh45lFrJ1 QtUz1PWnCY+q1JoS2JEd6Nd+2G9HXNfReep5JnPWGDFRZPZkvVmFgSDII7IGglyh7/N1 nHsd62sRIX5Z5phpeU0T2mEwNXP3y6TOzjG3rn9dCXYq+XZPUDqhXxbhrO0JlY4L0ZBs yIFQQ8isK9eiSq1ce8fafFqA9030tyWwB/18r32/hhRzcCAzWV0qFpu6/fqswWTX+YNw JD25f76EdoLiBvchLKcE8Uw/yPIGyb6g+ZE96bLIKp7OfjS8XS7awYOuRDVPM3D3xR4S eAGw== X-Gm-Message-State: AOAM533PgdzphCsWCUOOsoF7usAWsFMzFUpmuLwrdfdLEpsFr6bFFl14 fuWKoa1SnTJJyhni8W5ylrN7RYC1/2UHfSJZ X-Google-Smtp-Source: ABdhPJzZv2ucdGWYyijfrMlngk+LXpCb8k8LWNSL+F4KLF/Ku7H52sK0e7R7qqquQZfDfMEYJ4NXrQ== X-Received: by 2002:a17:902:221:: with SMTP id 30mr3106665plc.222.1598028851887; Fri, 21 Aug 2020 09:54:11 -0700 (PDT) Received: from localhost.localdomain ([115.96.123.214]) by smtp.googlemail.com with ESMTPSA id u15sm2420085pje.42.2020.08.21.09.54.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 21 Aug 2020 09:54:11 -0700 (PDT) From: Ani Sinha To: qemu-devel@nongnu.org Subject: [PATCH V8] Introduce a new flag for i440fx to disable PCI hotplug on the root bus Date: Fri, 21 Aug 2020 22:24:03 +0530 Message-Id: <20200821165403.26589-1-ani@anisinha.ca> X-Mailer: git-send-email 2.17.1 Received-SPF: none client-ip=2607:f8b0:4864:20::643; envelope-from=ani@anisinha.ca; helo=mail-pl1-x643.google.com X-detected-operating-system: by eggs.gnu.org: No matching host in p0f cache. That's all we know. X-Spam_score_int: -18 X-Spam_score: -1.9 X-Spam_bar: - X-Spam_report: (-1.9 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham 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: "Michael S. Tsirkin" , Aleksandar Markovic , Ani Sinha , Igor Mammedov , =?utf-8?q?Philippe_Mathieu-Daud=C3=A9?= , Aurelien Jarno Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" We introduce a new global flag 'acpi-root-pci-hotplug' for i440fx with which we can turn on or off PCI device hotplug on the root bus. This flag can be used to prevent all PCI devices from getting hotplugged or unplugged from the root PCI bus. This feature is targetted mostly towards Windows VMs. It is useful in cases where some hypervisor admins want to deploy guest VMs in a way so that the users of the guest OSes are not able to hot-eject certain PCI devices from the Windows system tray. Laine has explained the use case here in detail: https://www.redhat.com/archives/libvir-list/2020-February/msg00110.html Julia has resolved this issue for PCIE buses with the following commit: 530a0963184e57e71a5b538 ("pcie_root_port: Add hotplug disabling option") This commit attempts to introduce similar behavior for PCI root buses used in i440fx machine types (although in this case, we do not have a per-slot capability to turn hotplug on or off). Usage: -global PIIX4_PM.acpi-root-pci-hotplug=off By default, this option is enabled which means that hotplug is turned on for the PCI root bus. The previously existing flag 'acpi-pci-hotplug-with-bridge-support' for PCI-PCI bridges remain as is and can be used along with this new flag to control PCI hotplug on PCI bridges. This change has been tested using a Windows 2012R2 server guest image and also with a Windows 2019 server guest image on a Ubuntu 18.04 host using the latest master qemu from upstream. Signed-off-by: Ani Sinha --- hw/acpi/pcihp.c | 23 ++++++++++++++++++++++- hw/acpi/piix4.c | 5 ++++- include/hw/acpi/pcihp.h | 2 +- 3 files changed, 27 insertions(+), 3 deletions(-) Change Log: V7..V8: Cosmetic. Removed extra new line in the patch. Rebased to latest upstream master and retested with both versions of Windows. diff --git a/hw/acpi/pcihp.c b/hw/acpi/pcihp.c index 9e31ab2da4..39b1f74442 100644 --- a/hw/acpi/pcihp.c +++ b/hw/acpi/pcihp.c @@ -104,6 +104,24 @@ static void acpi_set_pci_info(void) } } +static void acpi_pcihp_disable_root_bus(void) +{ + static bool root_hp_disabled; + PCIBus *bus; + + if (root_hp_disabled) { + return; + } + + bus = find_i440fx(); + if (bus) { + /* setting the hotplug handler to NULL makes the bus non-hotpluggable */ + qbus_set_hotplug_handler(BUS(bus), NULL); + } + root_hp_disabled = true; + return; +} + static void acpi_pcihp_test_hotplug_bus(PCIBus *bus, void *opaque) { AcpiPciHpFind *find = opaque; @@ -209,8 +227,11 @@ static void acpi_pcihp_update(AcpiPciHpState *s) } } -void acpi_pcihp_reset(AcpiPciHpState *s) +void acpi_pcihp_reset(AcpiPciHpState *s, bool acpihp_root_off) { + if (acpihp_root_off) { + acpi_pcihp_disable_root_bus(); + } acpi_set_pci_info(); acpi_pcihp_update(s); } diff --git a/hw/acpi/piix4.c b/hw/acpi/piix4.c index 26bac4f16c..e6163bb6ce 100644 --- a/hw/acpi/piix4.c +++ b/hw/acpi/piix4.c @@ -78,6 +78,7 @@ typedef struct PIIX4PMState { AcpiPciHpState acpi_pci_hotplug; bool use_acpi_hotplug_bridge; + bool use_acpi_root_pci_hotplug; uint8_t disable_s3; uint8_t disable_s4; @@ -324,7 +325,7 @@ static void piix4_pm_reset(DeviceState *dev) pci_conf[0x5B] = 0x02; } pm_io_space_update(s); - acpi_pcihp_reset(&s->acpi_pci_hotplug); + acpi_pcihp_reset(&s->acpi_pci_hotplug, !s->use_acpi_root_pci_hotplug); } static void piix4_pm_powerdown_req(Notifier *n, void *opaque) @@ -635,6 +636,8 @@ static Property piix4_pm_properties[] = { DEFINE_PROP_UINT8(ACPI_PM_PROP_S4_VAL, PIIX4PMState, s4_val, 2), DEFINE_PROP_BOOL("acpi-pci-hotplug-with-bridge-support", PIIX4PMState, use_acpi_hotplug_bridge, true), + DEFINE_PROP_BOOL("acpi-root-pci-hotplug", PIIX4PMState, + use_acpi_root_pci_hotplug, true), DEFINE_PROP_BOOL("memory-hotplug-support", PIIX4PMState, acpi_memory_hotplug.is_enabled, true), DEFINE_PROP_END_OF_LIST(), diff --git a/include/hw/acpi/pcihp.h b/include/hw/acpi/pcihp.h index 8bc4a4c01d..02f4665767 100644 --- a/include/hw/acpi/pcihp.h +++ b/include/hw/acpi/pcihp.h @@ -67,7 +67,7 @@ void acpi_pcihp_device_unplug_request_cb(HotplugHandler *hotplug_dev, Error **errp); /* Called on reset */ -void acpi_pcihp_reset(AcpiPciHpState *s); +void acpi_pcihp_reset(AcpiPciHpState *s, bool acpihp_root_off); extern const VMStateDescription vmstate_acpi_pcihp_pci_status;