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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 304DBC432BE for ; Tue, 24 Aug 2021 17:08:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 192F3619EA for ; Tue, 24 Aug 2021 17:08:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239402AbhHXRJI (ORCPT ); Tue, 24 Aug 2021 13:09:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:46490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239422AbhHXRHC (ORCPT ); Tue, 24 Aug 2021 13:07:02 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 3DDB3619EA; Tue, 24 Aug 2021 16:59:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629824393; bh=OQ4I/BMOYSLVlMvcx9RjcvWe8+VZjWye4MX++2RqPys=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZYPeTDRMTPnnm8qTHLAEo/m78u3wEOT3Me6lvbMDKW2XxhepNThJtBxd1Ya6zIimw ds6WCjhaiEs8xRlvGuXIEWiOh54NWa9ScFztfR/pHzeiWBoCBJ1bvP+wROISINNGIp xtGHEAIQqt1FRjirGAqhAnhiF/bdbP3dDwusKezPUcwKOTvpx2ip2s5MZ6dt+CeJvd EhVsckFGixQdh0qL1G1S+QsBVDd3eh7EgdGXUefYGudl239rNbZ6Y5F6CCpmG9f+6V UuN6FREYgkAo/jMZ8MDJcoy0mdLWfkiPf2XN05LORQCLJHzVR9IunThrH+j9FjONd+ 9aBrDUthMx2bg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Eli Cohen , "Michael S . Tsirkin" , Sasha Levin Subject: [PATCH 5.10 44/98] vdpa/mlx5: Avoid destroying MR on empty iotlb Date: Tue, 24 Aug 2021 12:58:14 -0400 Message-Id: <20210824165908.709932-45-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210824165908.709932-1-sashal@kernel.org> References: <20210824165908.709932-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v5.x/stable-review/patch-5.10.61-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-5.10.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 5.10.61-rc1 X-KernelTest-Deadline: 2021-08-26T16:58+00:00 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Eli Cohen [ Upstream commit 08dbd5660232bede7916d8568003012c1182cc9a ] The current code treats an empty iotlb provdied in set_map() as a special case and destroy the memory region object. This must not be done since the virtqueue objects reference this MR. Doing so will cause the driver unload to emit errors and log timeouts caused by the firmware complaining on busy resources. This patch treats an empty iotlb as any other change of mapping. In this case, mlx5_vdpa_create_mr() will fail and the entire set_map() call to fail. This issue has not been encountered before but was seen to occur in a non-official version of qemu. Since qemu is a userspace program, the driver must protect against such case. Fixes: 94abbccdf291 ("vdpa/mlx5: Add shared memory registration code") Signed-off-by: Eli Cohen Link: https://lore.kernel.org/r/20210811053713.66658-1-elic@nvidia.com Signed-off-by: Michael S. Tsirkin Signed-off-by: Sasha Levin --- drivers/vdpa/mlx5/core/mr.c | 9 --------- 1 file changed, 9 deletions(-) diff --git a/drivers/vdpa/mlx5/core/mr.c b/drivers/vdpa/mlx5/core/mr.c index aa656f57bf5b..32c9925de473 100644 --- a/drivers/vdpa/mlx5/core/mr.c +++ b/drivers/vdpa/mlx5/core/mr.c @@ -454,11 +454,6 @@ out: mutex_unlock(&mr->mkey_mtx); } -static bool map_empty(struct vhost_iotlb *iotlb) -{ - return !vhost_iotlb_itree_first(iotlb, 0, U64_MAX); -} - int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb, bool *change_map) { @@ -466,10 +461,6 @@ int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *io int err = 0; *change_map = false; - if (map_empty(iotlb)) { - mlx5_vdpa_destroy_mr(mvdev); - return 0; - } mutex_lock(&mr->mkey_mtx); if (mr->initialized) { mlx5_vdpa_info(mvdev, "memory map update\n"); -- 2.30.2