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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 0E09CC433EF for ; Mon, 31 Jan 2022 09:17:11 +0000 (UTC) Received: from localhost ([::1]:56922 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1nESoA-0007RH-1t for qemu-devel@archiver.kernel.org; Mon, 31 Jan 2022 04:17:10 -0500 Received: from eggs.gnu.org ([209.51.188.92]:37340) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nESlO-0005Zy-8X for qemu-devel@nongnu.org; Mon, 31 Jan 2022 04:14:18 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:37984) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1nESlM-0005AJ-CM for qemu-devel@nongnu.org; Mon, 31 Jan 2022 04:14:17 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1643620455; h=from:from:reply-to: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=FhckrskEPNv79M5fE5OkrbvLe7aU7O9I8G8Gpid0TgA=; b=XswgV8Gq50xhTXGne0dJ+FP375DO4DyxqRX2ro9jUNDUHgbExpRSwCDyT0JMV69ePp4adR 6RG1ma93w93nGL2MdXYAO91vX5HtUhmLX1YMbiRbhLAijzOw8ZIk7IwcbDG/rXVA8tcjK/ SLQdUtmYYWEYvG1tIFRZdB/OE770hlk= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-106-Ofhlm_80PFOq4jDo9nEyCA-1; Mon, 31 Jan 2022 04:14:13 -0500 X-MC-Unique: Ofhlm_80PFOq4jDo9nEyCA-1 Received: by mail-wr1-f69.google.com with SMTP id c9-20020adfa709000000b001dde29c3202so4555697wrd.22 for ; Mon, 31 Jan 2022 01:14:13 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:reply-to:subject:to:cc:references:from :message-id:date:user-agent:mime-version:in-reply-to :content-transfer-encoding:content-language; bh=FhckrskEPNv79M5fE5OkrbvLe7aU7O9I8G8Gpid0TgA=; b=zqpJWiv6tTk53bN/j8b6qj0gR2ocJEwrmgMd2UWIkL8a3ZbumPD70X6TC2SzEbNg2p vdV/Bn9fxNqmcQX/lQG891n2Fx2r4SiJG26OP7qhCiAyoAi5KF59zUSWBEdWsXEphTVf H6b8jjORtOHuiduzyOejbwJco46NdEq9BtfSNBKkkla/nzGK7UkjKWVkOcrl92GoqS5h CEi8GpaICSe52hmN/LleuB5B/Ot+BHFuzQ6AkPnNr4cV/v+ndlXm3P/DJprBF+Cs7U4K 9fm1mzwA8k/2K0X+ZPOHPOR1Z+pwwdUVIDEJNvlxrJ8WYDaFzWh/Tu4eL80oju3D3wWe SN8A== X-Gm-Message-State: AOAM532XRD7Xx8D5hLGjA8MG3BwV6p4A0CvcwYbfLvmCRwCLLquZRqjq QbtkYkTcuqSBJT1SVnBfZ3/93AFl2JzftnCPAcYvHj+l+mSuHb5zcRK15yN8yiqTbGKEUfeY84o zssAN0fmYvM6fBVY= X-Received: by 2002:a05:6000:1569:: with SMTP id 9mr16808493wrz.512.1643620452497; Mon, 31 Jan 2022 01:14:12 -0800 (PST) X-Google-Smtp-Source: ABdhPJwxKNp6lstVNx7swOM/i92XbqozMBC5yYW9KOfcjFCvdo5j/jllMMefOA2weVK7TXORoe+pug== X-Received: by 2002:a05:6000:1569:: with SMTP id 9mr16808472wrz.512.1643620452235; Mon, 31 Jan 2022 01:14:12 -0800 (PST) Received: from ?IPv6:2a01:e0a:59e:9d80:527b:9dff:feef:3874? ([2a01:e0a:59e:9d80:527b:9dff:feef:3874]) by smtp.gmail.com with ESMTPSA id v5sm8218279wmh.19.2022.01.31.01.14.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 31 Jan 2022 01:14:11 -0800 (PST) Subject: Re: [PATCH v2 2/4] virtio-iommu: Default to bypass during boot To: Jean-Philippe Brucker References: <20220127142940.671333-1-jean-philippe@linaro.org> <20220127142940.671333-3-jean-philippe@linaro.org> From: Eric Auger Message-ID: <728c6b3f-c0ff-b924-e810-c686d82d789c@redhat.com> Date: Mon, 31 Jan 2022 10:14:10 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20220127142940.671333-3-jean-philippe@linaro.org> Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=eric.auger@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Received-SPF: pass client-ip=170.10.133.124; envelope-from=eric.auger@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -28 X-Spam_score: -2.9 X-Spam_bar: -- X-Spam_report: (-2.9 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.088, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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: , Reply-To: eric.auger@redhat.com Cc: lvivier@redhat.com, thuth@redhat.com, mst@redhat.com, cohuck@redhat.com, qemu-devel@nongnu.org, pasic@linux.ibm.com, pbonzini@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 1/27/22 3:29 PM, Jean-Philippe Brucker wrote: > Currently the virtio-iommu device must be programmed before it allows > DMA from any PCI device. This can make the VM entirely unusable when a > virtio-iommu driver isn't present, for example in a bootloader that > loads the OS from storage. > > Similarly to the other vIOMMU implementations, default to DMA bypassing > the IOMMU during boot. Add a "boot-bypass" property, defaulting to true, > that lets users change this behavior. > > Replace the VIRTIO_IOMMU_F_BYPASS feature, which didn't support bypass > before feature negotiation, with VIRTIO_IOMMU_F_BYPASS_CONFIG. > > Signed-off-by: Jean-Philippe Brucker Reviewed-by: Eric Auger Eric > --- > include/hw/virtio/virtio-iommu.h | 1 + > hw/virtio/virtio-iommu.c | 51 +++++++++++++++++++++++++++++--- > hw/virtio/trace-events | 4 ++- > 3 files changed, 51 insertions(+), 5 deletions(-) > > diff --git a/include/hw/virtio/virtio-iommu.h b/include/hw/virtio/virtio-iommu.h > index e2339e5b72..84391f8448 100644 > --- a/include/hw/virtio/virtio-iommu.h > +++ b/include/hw/virtio/virtio-iommu.h > @@ -58,6 +58,7 @@ struct VirtIOIOMMU { > GTree *domains; > QemuMutex mutex; > GTree *endpoints; > + bool boot_bypass; > }; > > #endif > diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c > index aa9c16a17b..ec02029bb6 100644 > --- a/hw/virtio/virtio-iommu.c > +++ b/hw/virtio/virtio-iommu.c > @@ -24,6 +24,7 @@ > #include "hw/qdev-properties.h" > #include "hw/virtio/virtio.h" > #include "sysemu/kvm.h" > +#include "sysemu/reset.h" > #include "qapi/error.h" > #include "qemu/error-report.h" > #include "trace.h" > @@ -728,8 +729,7 @@ static IOMMUTLBEntry virtio_iommu_translate(IOMMUMemoryRegion *mr, hwaddr addr, > .perm = IOMMU_NONE, > }; > > - bypass_allowed = virtio_vdev_has_feature(&s->parent_obj, > - VIRTIO_IOMMU_F_BYPASS); > + bypass_allowed = s->config.bypass; > > sid = virtio_iommu_get_bdf(sdev); > > @@ -831,13 +831,37 @@ static void virtio_iommu_get_config(VirtIODevice *vdev, uint8_t *config_data) > out_config->domain_range.start = cpu_to_le32(dev_config->domain_range.start); > out_config->domain_range.end = cpu_to_le32(dev_config->domain_range.end); > out_config->probe_size = cpu_to_le32(dev_config->probe_size); > + out_config->bypass = dev_config->bypass; > > trace_virtio_iommu_get_config(dev_config->page_size_mask, > dev_config->input_range.start, > dev_config->input_range.end, > dev_config->domain_range.start, > dev_config->domain_range.end, > - dev_config->probe_size); > + dev_config->probe_size, > + dev_config->bypass); > +} > + > +static void virtio_iommu_set_config(VirtIODevice *vdev, > + const uint8_t *config_data) > +{ > + VirtIOIOMMU *dev = VIRTIO_IOMMU(vdev); > + struct virtio_iommu_config *dev_config = &dev->config; > + const struct virtio_iommu_config *in_config = (void *)config_data; > + > + if (in_config->bypass != dev_config->bypass) { > + if (!virtio_vdev_has_feature(vdev, VIRTIO_IOMMU_F_BYPASS_CONFIG)) { > + virtio_error(vdev, "cannot set config.bypass"); > + return; > + } else if (in_config->bypass != 0 && in_config->bypass != 1) { > + virtio_error(vdev, "invalid config.bypass value '%u'", > + in_config->bypass); > + return; > + } > + dev_config->bypass = in_config->bypass; > + } > + > + trace_virtio_iommu_set_config(in_config->bypass); > } > > static uint64_t virtio_iommu_get_features(VirtIODevice *vdev, uint64_t f, > @@ -963,6 +987,19 @@ static int virtio_iommu_set_page_size_mask(IOMMUMemoryRegion *mr, > return 0; > } > > +static void virtio_iommu_system_reset(void *opaque) > +{ > + VirtIOIOMMU *s = opaque; > + > + trace_virtio_iommu_system_reset(); > + > + /* > + * config.bypass is sticky across device reset, but should be restored on > + * system reset > + */ > + s->config.bypass = s->boot_bypass; > +} > + > static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) > { > VirtIODevice *vdev = VIRTIO_DEVICE(dev); > @@ -988,9 +1025,9 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) > virtio_add_feature(&s->features, VIRTIO_IOMMU_F_INPUT_RANGE); > virtio_add_feature(&s->features, VIRTIO_IOMMU_F_DOMAIN_RANGE); > virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MAP_UNMAP); > - virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS); > virtio_add_feature(&s->features, VIRTIO_IOMMU_F_MMIO); > virtio_add_feature(&s->features, VIRTIO_IOMMU_F_PROBE); > + virtio_add_feature(&s->features, VIRTIO_IOMMU_F_BYPASS_CONFIG); > > qemu_mutex_init(&s->mutex); > > @@ -1001,6 +1038,8 @@ static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) > } else { > error_setg(errp, "VIRTIO-IOMMU is not attached to any PCI bus!"); > } > + > + qemu_register_reset(virtio_iommu_system_reset, s); > } > > static void virtio_iommu_device_unrealize(DeviceState *dev) > @@ -1008,6 +1047,8 @@ static void virtio_iommu_device_unrealize(DeviceState *dev) > VirtIODevice *vdev = VIRTIO_DEVICE(dev); > VirtIOIOMMU *s = VIRTIO_IOMMU(dev); > > + qemu_unregister_reset(virtio_iommu_system_reset, s); > + > g_hash_table_destroy(s->as_by_busptr); > if (s->domains) { > g_tree_destroy(s->domains); > @@ -1164,6 +1205,7 @@ static const VMStateDescription vmstate_virtio_iommu = { > > static Property virtio_iommu_properties[] = { > DEFINE_PROP_LINK("primary-bus", VirtIOIOMMU, primary_bus, "PCI", PCIBus *), > + DEFINE_PROP_BOOL("boot-bypass", VirtIOIOMMU, boot_bypass, true), > DEFINE_PROP_END_OF_LIST(), > }; > > @@ -1180,6 +1222,7 @@ static void virtio_iommu_class_init(ObjectClass *klass, void *data) > vdc->unrealize = virtio_iommu_device_unrealize; > vdc->reset = virtio_iommu_device_reset; > vdc->get_config = virtio_iommu_get_config; > + vdc->set_config = virtio_iommu_set_config; > vdc->get_features = virtio_iommu_get_features; > vdc->set_status = virtio_iommu_set_status; > vdc->vmsd = &vmstate_virtio_iommu_device; > diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events > index f7ad6be5fb..a5102eac9e 100644 > --- a/hw/virtio/trace-events > +++ b/hw/virtio/trace-events > @@ -89,9 +89,11 @@ virtio_mmio_setting_irq(int level) "virtio_mmio setting IRQ %d" > > # virtio-iommu.c > virtio_iommu_device_reset(void) "reset!" > +virtio_iommu_system_reset(void) "system reset!" > virtio_iommu_get_features(uint64_t features) "device supports features=0x%"PRIx64 > virtio_iommu_device_status(uint8_t status) "driver status = %d" > -virtio_iommu_get_config(uint64_t page_size_mask, uint64_t start, uint64_t end, uint32_t domain_start, uint32_t domain_end, uint32_t probe_size) "page_size_mask=0x%"PRIx64" input range start=0x%"PRIx64" input range end=0x%"PRIx64" domain range start=%d domain range end=%d probe_size=0x%x" > +virtio_iommu_get_config(uint64_t page_size_mask, uint64_t start, uint64_t end, uint32_t domain_start, uint32_t domain_end, uint32_t probe_size, uint8_t bypass) "page_size_mask=0x%"PRIx64" input range start=0x%"PRIx64" input range end=0x%"PRIx64" domain range start=%d domain range end=%d probe_size=0x%x bypass=0x%x" > +virtio_iommu_set_config(uint8_t bypass) "bypass=0x%x" > virtio_iommu_attach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d" > virtio_iommu_detach(uint32_t domain_id, uint32_t ep_id) "domain=%d endpoint=%d" > virtio_iommu_map(uint32_t domain_id, uint64_t virt_start, uint64_t virt_end, uint64_t phys_start, uint32_t flags) "domain=%d virt_start=0x%"PRIx64" virt_end=0x%"PRIx64 " phys_start=0x%"PRIx64" flags=%d"