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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_GIT 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 37FFBC169C4 for ; Mon, 11 Feb 2019 07:52:05 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 DED3120811 for ; Mon, 11 Feb 2019 07:52:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DED3120811 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from lists.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 43ydKb0VWDzDqNX for ; Mon, 11 Feb 2019 18:52:03 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=ozlabs.ru (client-ip=107.173.13.209; helo=ozlabs.ru; envelope-from=aik@ozlabs.ru; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=ozlabs.ru Received: from ozlabs.ru (ozlabs.ru [107.173.13.209]) by lists.ozlabs.org (Postfix) with ESMTP id 43ydGV3mx8zDqNC for ; Mon, 11 Feb 2019 18:49:22 +1100 (AEDT) Received: from fstn1-p1.ozlabs.ibm.com (localhost [IPv6:::1]) by ozlabs.ru (Postfix) with ESMTP id 59F58AE80013; Mon, 11 Feb 2019 02:49:19 -0500 (EST) From: Alexey Kardashevskiy To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH kernel] vfio/spapr_tce: Skip unsetting already unset table Date: Mon, 11 Feb 2019 18:49:17 +1100 Message-Id: <20190211074917.125723-1-aik@ozlabs.ru> X-Mailer: git-send-email 2.17.1 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Alexey Kardashevskiy , Alex Williamson , kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, David Gibson Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" VFIO TCE IOMMU v2 owns IOMMU tables so when detach a IOMMU group from a container, we need to unset those from a group so we call unset_window() so do we unconditionally. We also unset tables when removing a DMA window via the VFIO_IOMMU_SPAPR_TCE_REMOVE ioctl. The window removal checks if the table actually exists (hidden inside tce_iommu_find_table()) but the group detaching does not so the user may see duplicating messages: pci 0009:03 : [PE# fd] Removing DMA window #0 pci 0009:03 : [PE# fd] Removing DMA window #1 pci 0009:03 : [PE# fd] Removing DMA window #0 pci 0009:03 : [PE# fd] Removing DMA window #1 At the moment this is not a problem as the second invocation of unset_window() writes zeroes to the HW registers again and exits early as there is no table. Signed-off-by: Alexey Kardashevskiy --- When doing VFIO PCI hot unplug, first we remove the DMA window and set container->tables[num] - this is a first couple of messages. Then we detach the group and then we see another couple of the same messages which confused myself. --- drivers/vfio/vfio_iommu_spapr_tce.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/vfio/vfio_iommu_spapr_tce.c b/drivers/vfio/vfio_iommu_spapr_tce.c index c424913..8dbb270 100644 --- a/drivers/vfio/vfio_iommu_spapr_tce.c +++ b/drivers/vfio/vfio_iommu_spapr_tce.c @@ -1235,7 +1235,8 @@ static void tce_iommu_release_ownership_ddw(struct tce_container *container, } for (i = 0; i < IOMMU_TABLE_GROUP_MAX_TABLES; ++i) - table_group->ops->unset_window(table_group, i); + if (container->tables[i]) + table_group->ops->unset_window(table_group, i); table_group->ops->release_ownership(table_group); } -- 2.17.1