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 B82ABC433F5 for ; Mon, 18 Oct 2021 11:38:04 +0000 (UTC) Received: from smtp2.osuosl.org (smtp2.osuosl.org [140.211.166.133]) (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 6173A6103D for ; Mon, 18 Oct 2021 11:38:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 6173A6103D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp2.osuosl.org (Postfix) with ESMTP id 2B821403F0; Mon, 18 Oct 2021 11:38:04 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp2.osuosl.org ([127.0.0.1]) by localhost (smtp2.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id qBvtVpphZJUY; Mon, 18 Oct 2021 11:38:03 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp2.osuosl.org (Postfix) with ESMTPS id CCA6C403ED; Mon, 18 Oct 2021 11:38:02 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id AE479C000F; Mon, 18 Oct 2021 11:38:02 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [IPv6:2605:bc80:3010::136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 87825C000D; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 75CD6608C7; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HQmhc-FfIy_L; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by smtp3.osuosl.org (Postfix) with ESMTPS id E31456059B; Mon, 18 Oct 2021 11:38:00 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 5DBB8450; Mon, 18 Oct 2021 13:37:56 +0200 (CEST) Date: Mon, 18 Oct 2021 13:37:55 +0200 From: "joro@8bytes.org" To: "Tian, Kevin" Subject: Re: [PATCH 0/5] iommu/virtio: Add identity domains Message-ID: References: <20211013121052.518113-1-jean-philippe@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Cc: Jean-Philippe Brucker , "mst@redhat.com" , "jasowang@redhat.com" , "virtualization@lists.linux-foundation.org" , "iommu@lists.linux-foundation.org" , "Boeuf, Sebastien" , "will@kernel.org" X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Thu, Oct 14, 2021 at 03:00:38AM +0000, Tian, Kevin wrote: > I saw a concept of deferred attach in iommu core. See iommu_is_ > attach_deferred(). Currently this is vendor specific and I haven't > looked into the exact reason why some vendor sets it now. Just > be curious whether the same reason might be applied to virtio-iommu. The reason for attach_deferred is kdump support, where the IOMMU driver needs to keep the mappings from the old kernel until the device driver of the new kernel takes over. Regards, Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu 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 059B2C433EF for ; Mon, 18 Oct 2021 11:38:05 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (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 A4DE461077 for ; Mon, 18 Oct 2021 11:38:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org A4DE461077 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id 739E1404F6; Mon, 18 Oct 2021 11:38:04 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id A5_zxGQA5Plq; Mon, 18 Oct 2021 11:38:03 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by smtp4.osuosl.org (Postfix) with ESMTPS id 334AE404E4; Mon, 18 Oct 2021 11:38:03 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id DA038C000D; Mon, 18 Oct 2021 11:38:02 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [IPv6:2605:bc80:3010::136]) by lists.linuxfoundation.org (Postfix) with ESMTP id 87825C000D; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 75CD6608C7; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id HQmhc-FfIy_L; Mon, 18 Oct 2021 11:38:01 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 X-Greylist: from auto-whitelisted by SQLgrey-1.8.0 Received: from theia.8bytes.org (8bytes.org [IPv6:2a01:238:4383:600:38bc:a715:4b6d:a889]) by smtp3.osuosl.org (Postfix) with ESMTPS id E31456059B; Mon, 18 Oct 2021 11:38:00 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 5DBB8450; Mon, 18 Oct 2021 13:37:56 +0200 (CEST) Date: Mon, 18 Oct 2021 13:37:55 +0200 From: "joro@8bytes.org" To: "Tian, Kevin" Subject: Re: [PATCH 0/5] iommu/virtio: Add identity domains Message-ID: References: <20211013121052.518113-1-jean-philippe@linaro.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: Cc: Jean-Philippe Brucker , "mst@redhat.com" , "virtualization@lists.linux-foundation.org" , "eric.auger@redhat.com" , "iommu@lists.linux-foundation.org" , "Boeuf, Sebastien" , "will@kernel.org" X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On Thu, Oct 14, 2021 at 03:00:38AM +0000, Tian, Kevin wrote: > I saw a concept of deferred attach in iommu core. See iommu_is_ > attach_deferred(). Currently this is vendor specific and I haven't > looked into the exact reason why some vendor sets it now. Just > be curious whether the same reason might be applied to virtio-iommu. The reason for attach_deferred is kdump support, where the IOMMU driver needs to keep the mappings from the old kernel until the device driver of the new kernel takes over. Regards, Joerg _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization