From patchwork Thu Mar 10 07:52:11 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 12776007 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21B18C433FE for ; Thu, 10 Mar 2022 07:52:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240160AbiCJHxY (ORCPT ); Thu, 10 Mar 2022 02:53:24 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34560 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240087AbiCJHxX (ORCPT ); Thu, 10 Mar 2022 02:53:23 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 1E1D81323ED for ; Wed, 9 Mar 2022 23:52:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1646898741; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=d/kJbw1ceOFiXhO5YIO+i0r0c+TxsMqa/iGcWfOLU3I=; b=Minv1FdXstaXqnb44YLPJjpzR+M2/UVBfT6TbxAUKmpZFEXQJEXFc4QubEAzjiHE2YMboI FO6vMgjpemZ7fGQ6ph+nxVInZfosH5QFkPjvxIs0Ld+JVy5C+vvN2dGpZs/tO43TvTrZnE 4apT4AySu5o77wE3zx4+6zdflZLe52c= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-48-5l8F3TN-PgeNTt8YBimUDQ-1; Thu, 10 Mar 2022 02:52:17 -0500 X-MC-Unique: 5l8F3TN-PgeNTt8YBimUDQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A65FD51DC; Thu, 10 Mar 2022 07:52:16 +0000 (UTC) Received: from localhost.localdomain (ovpn-13-194.pek2.redhat.com [10.72.13.194]) by smtp.corp.redhat.com (Postfix) with ESMTP id D69437A220; Thu, 10 Mar 2022 07:52:13 +0000 (UTC) From: Jason Wang To: mst@redhat.com Cc: kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jason Wang , Eli Cohen , Anirudh Rayabharam Subject: [PATCH] vhost: allow batching hint without size Date: Thu, 10 Mar 2022 15:52:11 +0800 Message-Id: <20220310075211.4801-1-jasowang@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Commit e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb entries") tries to reject the IOTLB message whose size is zero. But the size is not necessarily meaningful, one example is the batching hint, so the commit breaks that. Fixing this be reject zero size message only if the message is used to update/invalidate the IOTLB. Fixes: e2ae38cf3d91 ("vhost: fix hung thread due to erroneous iotlb entries") Reported-by: Eli Cohen Cc: Anirudh Rayabharam Signed-off-by: Jason Wang Tested-by: Eli Cohen --- drivers/vhost/vhost.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index 082380c03a3e..1768362115c6 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c @@ -1170,7 +1170,9 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev, goto done; } - if (msg.size == 0) { + if ((msg.type == VHOST_IOTLB_UPDATE || + msg.type == VHOST_IOTLB_INVALIDATE) && + msg.size == 0) { ret = -EINVAL; goto done; }