From owner-svn-src-head@freebsd.org Fri Aug 5 08:57:52 2016 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id BC5B6BAE7BA; Fri, 5 Aug 2016 08:57:52 +0000 (UTC) (envelope-from sephe@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 8BB5D1731; Fri, 5 Aug 2016 08:57:52 +0000 (UTC) (envelope-from sephe@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id u758vpGN074775; Fri, 5 Aug 2016 08:57:51 GMT (envelope-from sephe@FreeBSD.org) Received: (from sephe@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id u758vpRi074774; Fri, 5 Aug 2016 08:57:51 GMT (envelope-from sephe@FreeBSD.org) Message-Id: <201608050857.u758vpRi074774@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: sephe set sender to sephe@FreeBSD.org using -f From: Sepherosa Ziehau Date: Fri, 5 Aug 2016 08:57:51 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r303764 - head/sys/dev/hyperv/vmbus X-SVN-Group: head MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Aug 2016 08:57:52 -0000 Author: sephe Date: Fri Aug 5 08:57:51 2016 New Revision: 303764 URL: https://svnweb.freebsd.org/changeset/base/303764 Log: hyperv/vmbus: Only make sure the TX bufring will not be closed. KVP can write data, whose size is > 1/2 TX bufring size. MFC after: 1 week Sponsored by: Microsoft OSTC Differential Revision: https://reviews.freebsd.org/D7414 Modified: head/sys/dev/hyperv/vmbus/vmbus_brvar.h Modified: head/sys/dev/hyperv/vmbus/vmbus_brvar.h ============================================================================== --- head/sys/dev/hyperv/vmbus/vmbus_brvar.h Fri Aug 5 06:23:06 2016 (r303763) +++ head/sys/dev/hyperv/vmbus/vmbus_brvar.h Fri Aug 5 08:57:51 2016 (r303764) @@ -74,8 +74,12 @@ struct sysctl_oid; static __inline int vmbus_txbr_maxpktsz(const struct vmbus_txbr *tbr) { - /* 1/2 data size */ - return (tbr->txbr_dsize / 2); + /* + * - 64 bits for the trailing start index (- sizeof(uint64_t)). + * - The rindex and windex can't be same (- 1). See + * the comment near vmbus_bufring.br_{r,w}index. + */ + return (tbr->txbr_dsize - sizeof(uint64_t) - 1); } void vmbus_br_sysctl_create(struct sysctl_ctx_list *ctx,