From patchwork Tue Apr 12 10:43:15 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wei Liu X-Patchwork-Id: 8809311 Return-Path: X-Original-To: patchwork-qemu-devel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 21A2CC0553 for ; Tue, 12 Apr 2016 10:43:25 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id AE2742035E for ; Tue, 12 Apr 2016 10:43:20 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 189CB20138 for ; Tue, 12 Apr 2016 10:43:16 +0000 (UTC) Received: from localhost ([::1]:46688 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1apvmt-00040o-HW for patchwork-qemu-devel@patchwork.kernel.org; Tue, 12 Apr 2016 06:43:15 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60621) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1apvlc-0001PL-DM for qemu-devel@nongnu.org; Tue, 12 Apr 2016 06:41:57 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1apvlX-00075b-K9 for qemu-devel@nongnu.org; Tue, 12 Apr 2016 06:41:56 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:2787) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1apvlX-000735-G8 for qemu-devel@nongnu.org; Tue, 12 Apr 2016 06:41:51 -0400 X-IronPort-AV: E=Sophos;i="5.24,473,1454976000"; d="scan'208";a="353150967" From: Wei Liu To: Date: Tue, 12 Apr 2016 11:43:15 +0100 Message-ID: <1460457796-1779-3-git-send-email-wei.liu2@citrix.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1460457796-1779-1-git-send-email-wei.liu2@citrix.com> References: <1460457796-1779-1-git-send-email-wei.liu2@citrix.com> MIME-Version: 1.0 X-DLP: MIA1 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 66.165.176.63 Subject: [Qemu-devel] [PATCH v2 2/3] xenfb: move xen_rmb to the correct location X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anthony Perard , Xen-devel , Stefano Stabellini , Wei Liu Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP It should be placed before first time producer and consumer are used. Signed-off-by: Wei Liu --- Cc: Stefano Stabellini Cc: Anthony Perard Backport candidate to our own tree. --- hw/display/xenfb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c index 9866dfd..7f4fad7 100644 --- a/hw/display/xenfb.c +++ b/hw/display/xenfb.c @@ -775,10 +775,10 @@ static void xenfb_handle_events(struct XenFB *xenfb) prod = page->out_prod; out_cons = page->out_cons; + xen_rmb(); if (prod - out_cons > XENFB_OUT_RING_LEN) { return; } - xen_rmb(); /* ensure we see ring contents up to prod */ for (cons = out_cons; cons != prod; cons++) { union xenfb_out_event *event = &XENFB_OUT_RING_REF(page, cons); uint8_t type = event->type;