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=-9.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 1760FC433E2 for ; Tue, 1 Sep 2020 06:28:40 +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 BB2872071B for ; Tue, 1 Sep 2020 06:28:39 +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="ItoegMdY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BB2872071B 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+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57194 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kCzmY-0003Iy-Vd for qemu-devel@archiver.kernel.org; Tue, 01 Sep 2020 02:28:39 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45740) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kCzlj-0002S3-I5 for qemu-devel@nongnu.org; Tue, 01 Sep 2020 02:27:47 -0400 Received: from mail-wm1-x341.google.com ([2a00:1450:4864:20::341]:33065) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1kCzlh-0001ic-CH for qemu-devel@nongnu.org; Tue, 01 Sep 2020 02:27:47 -0400 Received: by mail-wm1-x341.google.com with SMTP id e11so234972wme.0 for ; Mon, 31 Aug 2020 23:27:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=anisinha-ca.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=tuxcbYwpybOb4Ni8MRXT1mk/aPk9jMOeobYxqoeKaEk=; b=ItoegMdYDq9JKd6ZOKJRwqGKKiC/tolhcZwxFWXiWn62GamXVDdY4/+uVO3joIljJ7 uzw129xRxqp9kXfnCk66QEElS96g71DgdBbqfPbcxq1LGzhy+n1XiBsbMbWvpz7/O4Wf m1mITumInmDU5FPm/xAcWqjkRF6hj7ZZlb0gHbH7OOcwptEuDdgTh8lgrm1D+5Hb9HVi 15gp0x3tn0n47WAXeKGWr7IESM1Y5Ja7fAWdacXTHNarTLFE5FCSYNTns+uCEf5HyW59 irmoaDo/hkRZ1OzFxPaCSt/Z5r8vWnxPM1fOGwesOt0b7I41LoSktocftEz6pvQiBlXK Vy2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=tuxcbYwpybOb4Ni8MRXT1mk/aPk9jMOeobYxqoeKaEk=; b=g5+38PZotvh4YKZmqzs10jHIE31km1lA3LYZfnpBenWJq4qdCN6O6CmCuvWBeo6goT ShMlT86es7tcRcJfm6rflshdMScfJJi2sA47pxDUJAmp0z/wtqMMpUPLzCYCrlrx5ELk cWNGFIy014aOsbxX0+1ZpWwxPjWqcxl7+sgHzJTRZGmLgZ5bcUO7S+rFXlrjxpwCSBQm poxsJfYvLfBpcR0w/1lTvgDFRv4PZIU9vhRtRLL9kJREe3jZU1v1rHB8K7Ldoy4Id1NM 0Rfp5zXWK71zmksoE9tWI6aSGmFoBBfiwsG1btoYgWvBa/fE8n086YDIP71AsEkmfjYb wz+A== X-Gm-Message-State: AOAM530aV1d4a4WWqENOGgB22DFmWC2k62tw9SZccdGRv7VHC5z5l8zS XtnGtclfFn1J31QHgtffYgLlU5svuwFX3hpZcqmffw== X-Google-Smtp-Source: ABdhPJwdm4fqDC4Tga1FGGsAaap4+kT8BG6vxiCaHsn4UqGX3kwmit5CapORGTvrkf5fRQTc05kEKLDPD8LteUyT/Aw= X-Received: by 2002:a1c:e256:: with SMTP id z83mr182833wmg.137.1598941663618; Mon, 31 Aug 2020 23:27:43 -0700 (PDT) MIME-Version: 1.0 References: <20200827133954.2118749-1-mst@redhat.com> <20200827133954.2118749-7-mst@redhat.com> <20200827194115.673f94de@imammedo-mac> <20200828114907.42961cd3@redhat.com> In-Reply-To: From: Ani Sinha Date: Tue, 1 Sep 2020 11:57:32 +0530 Message-ID: Subject: Re: [PULL 06/13] Introduce a new flag for i440fx to disable PCI hotplug on the root bus To: Julia Suvorova Content-Type: text/plain; charset="UTF-8" Received-SPF: none client-ip=2a00:1450:4864:20::341; envelope-from=ani@anisinha.ca; helo=mail-wm1-x341.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: Peter Maydell , "Michael S. Tsirkin" , QEMU Developers , Aleksandar Markovic , Igor Mammedov , =?UTF-8?Q?Philippe_Mathieu=2DDaud=C3=A9?= , Aurelien Jarno Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Fri, Aug 28, 2020 at 6:40 PM Julia Suvorova wrote: > > On Fri, Aug 28, 2020 at 11:53 AM Ani Sinha wrote: > > > > > > Ani > > On Aug 28, 2020, 15:19 +0530, Igor Mammedov , wrote: > > > > On Thu, 27 Aug 2020 23:29:34 +0530 > > > > Ani Sinha wrote: > > > > > > On Thu, Aug 27, 2020 at 11:11 PM Igor Mammedov wrote: > > > > > > On Thu, 27 Aug 2020 09:40:34 -0400 > > > > "Michael S. Tsirkin" wrote: > > > > > > From: Ani Sinha > > > > > > 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 > > > > Message-Id: <20200821165403.26589-1-ani@anisinha.ca> > > > > Reviewed-by: Michael S. Tsirkin > > > > Signed-off-by: Michael S. Tsirkin > > > > > > > > Tested-by: Igor Mammedov > > > > Reviewed-by: Igor Mammedov > > > > A glitch in scripts? > > > > I didn't review nor tested this (v8) version > > > > > > oops! I am so eager to get this done and dusted :) > > > > it's merged now, > > > > > > Wait it merged without your review? > > Yeah, not only added into the pull request, but actually merged. > > > > > can you add a test case for it please? > > > > > > You can use test_acpi_piix4_tcg_bridge() as model. > > > > See header comment at the top of bios-tables-test.c > > > > for how to prepare and submit testcase. > > > > > > Will get on it. > > Also, while the whole approach seems good to me, it leaves the hotplug > registers initialized (see build_piix4_pci_hotplug()), even if both > root and bridges hotplug are disabled. Which you can exploit by > writing something like this to the io registers: > > outl 0xae10 0 > outl 0xae08 your_slot > > And because of these quite interesting lines the device will be > successfully unplugged: > > static PCIBus *acpi_pcihp_find_hotplug_bus(AcpiPciHpState *s, int bsel) > { > ... > /* Make bsel 0 eject root bus if bsel property is not set, > * for compatibility with non acpi setups. > * TODO: really needed? > */ > if (!bsel && !find.bus) { > find.bus = s->root; > } > return find.bus; > } > I have sent a patch to address this. Please review. > Could you please cover both issues in the follow-up patches? Also julia, looking at the code, should we also set pm->pcihp_io_len to 0 as well in case where bridge and pci bus 0 hotplugs are both disabled? This is because I see: /* reserve PCIHP resources */ if (pm->pcihp_io_len) { which we do not want to do if PCI hotplug is disabled altogether? > > Best regards, Julia Suvorova. > > > > > > > > > --- > > > > include/hw/acpi/pcihp.h | 2 +- > > > > hw/acpi/pcihp.c | 23 ++++++++++++++++++++++- > > > > hw/acpi/piix4.c | 5 ++++- > > > > 3 files changed, 27 insertions(+), 3 deletions(-) > > > > > > 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; > > > > > > 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(), > > > > > > > > >