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=0.4 required=3.0 tests=DATE_IN_PAST_06_12, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS autolearn=no 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 CBD48C1B0F2 for ; Wed, 20 Jun 2018 06:16:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 763B420652 for ; Wed, 20 Jun 2018 06:16:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 763B420652 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=vmware.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754226AbeFTGQn (ORCPT ); Wed, 20 Jun 2018 02:16:43 -0400 Received: from ex13-edg-ou-001.vmware.com ([208.91.0.189]:14595 "EHLO EX13-EDG-OU-001.vmware.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752871AbeFTGPQ (ORCPT ); Wed, 20 Jun 2018 02:15:16 -0400 Received: from sc9-mailhost2.vmware.com (10.113.161.72) by EX13-EDG-OU-001.vmware.com (10.113.208.155) with Microsoft SMTP Server id 15.0.1156.6; Tue, 19 Jun 2018 23:14:41 -0700 Received: from sc2-haas01-esx0118.eng.vmware.com (sc2-haas01-esx0118.eng.vmware.com [10.172.44.118]) by sc9-mailhost2.vmware.com (Postfix) with ESMTP id A1AA8B0AA2; Tue, 19 Jun 2018 23:15:15 -0700 (PDT) From: Nadav Amit To: Greg Kroah-Hartman CC: Xavier Deguillard , Arnd Bergmann , , Nadav Amit , Subject: [PATCH v3 4/7] vmw_balloon: fix VMCI use when balloon built into kernel Date: Tue, 19 Jun 2018 16:00:27 -0700 Message-ID: <20180619230030.112906-5-namit@vmware.com> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180619230030.112906-1-namit@vmware.com> References: <20180619230030.112906-1-namit@vmware.com> MIME-Version: 1.0 Content-Type: text/plain Received-SPF: None (EX13-EDG-OU-001.vmware.com: namit@vmware.com does not designate permitted sender hosts) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, when all modules, including VMCI and VMware balloon are built into the kernel, the initialization of the balloon happens before the VMCI is probed. As a result, the balloon fails to initialize the VMCI doorbell, which it uses to get asynchronous requests for balloon size changes. The problem can be seen in the logs, in the form of the following message: "vmw_balloon: failed to initialize vmci doorbell" The driver would work correctly but slightly less efficiently, probing for requests periodically. This patch changes the balloon to be initialized using late_initcall() instead of module_init() to address this issue. It does not address a situation in which VMCI is built as a module and the balloon is built into the kernel. Fixes: 48e3d668b790 ("VMware balloon: Enable notification via VMCI") Cc: stable@vger.kernel.org Reviewed-by: Xavier Deguillard Signed-off-by: Nadav Amit --- drivers/misc/vmw_balloon.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/misc/vmw_balloon.c b/drivers/misc/vmw_balloon.c index a7df4c24a28d..e7cfc85f6961 100644 --- a/drivers/misc/vmw_balloon.c +++ b/drivers/misc/vmw_balloon.c @@ -1297,7 +1297,14 @@ static int __init vmballoon_init(void) return 0; } -module_init(vmballoon_init); + +/* + * Using late_initcall() instead of module_init() allows the balloon to use the + * VMCI doorbell even when the balloon is built into the kernel. Otherwise the + * VMCI is probed only after the balloon is initialized. If the balloon is used + * as a module, late_initcall() is equivalent to module_init(). + */ +late_initcall(vmballoon_init); static void __exit vmballoon_exit(void) { -- 2.17.0