From patchwork Fri Aug 14 00:07:03 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: KY Srinivasan X-Patchwork-Id: 7011391 Return-Path: X-Original-To: patchwork-linux-scsi@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 DA425C05AC for ; Thu, 13 Aug 2015 22:41:37 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1388820445 for ; Thu, 13 Aug 2015 22:41:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0BE2D20444 for ; Thu, 13 Aug 2015 22:41:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754296AbbHMWlW (ORCPT ); Thu, 13 Aug 2015 18:41:22 -0400 Received: from p3plsmtps2ded01.prod.phx3.secureserver.net ([208.109.80.58]:39388 "EHLO p3plsmtps2ded01.prod.phx3.secureserver.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752698AbbHMWlV (ORCPT ); Thu, 13 Aug 2015 18:41:21 -0400 Received: from linuxonhyperv.com ([72.167.245.219]) by p3plsmtps2ded01.prod.phx3.secureserver.net with : DED : id 4NhE1r0154kklxU01NhEY6; Thu, 13 Aug 2015 15:41:15 -0700 x-originating-ip: 72.167.245.219 Received: by linuxonhyperv.com (Postfix, from userid 507) id DA02019025C; Thu, 13 Aug 2015 17:07:04 -0700 (PDT) From: "K. Y. Srinivasan" To: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, ohering@suse.com, jbottomley@parallels.com, hch@infradead.org, linux-scsi@vger.kernel.org, apw@canonical.com, vkuznets@redhat.com, jasowang@redhat.com Cc: Dexuan Cui , "K. Y. Srinivasan" Subject: [PATCH 1/1] Drivers: hv: vmbus: fix init_vp_index() for reloading hv_netvsc Date: Thu, 13 Aug 2015 17:07:03 -0700 Message-Id: <1439510823-16280-1-git-send-email-kys@microsoft.com> X-Mailer: git-send-email 1.7.4.1 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, 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 From: Dexuan Cui This fixes the recent commit 3b71107d73b16074afa7658f3f0fcf837aabfe24: Drivers: hv: vmbus: Further improve CPU affiliation logic Without the fix, reloading hv_netvsc hangs the guest. Signed-off-by: Dexuan Cui Signed-off-by: K. Y. Srinivasan --- drivers/hv/channel_mgmt.c | 17 +++++++++++++++++ 1 files changed, 17 insertions(+), 0 deletions(-) diff --git a/drivers/hv/channel_mgmt.c b/drivers/hv/channel_mgmt.c index 3ab4753..8a4105c 100644 --- a/drivers/hv/channel_mgmt.c +++ b/drivers/hv/channel_mgmt.c @@ -204,6 +204,8 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) spin_lock_irqsave(&vmbus_connection.channel_lock, flags); list_del(&channel->listentry); spin_unlock_irqrestore(&vmbus_connection.channel_lock, flags); + + primary_channel = channel; } else { primary_channel = channel->primary_channel; spin_lock_irqsave(&primary_channel->lock, flags); @@ -211,6 +213,14 @@ void hv_process_channel_removal(struct vmbus_channel *channel, u32 relid) primary_channel->num_sc--; spin_unlock_irqrestore(&primary_channel->lock, flags); } + + /* + * We need to free the bit for init_vp_index() to work in the case + * of sub-channel, when we reload drivers like hv_netvsc. + */ + cpumask_clear_cpu(channel->target_cpu, + &primary_channel->alloced_cpus_in_node); + free_channel(channel); } @@ -457,6 +467,13 @@ static void init_vp_index(struct vmbus_channel *channel, const uuid_le *type_gui continue; } + /* + * NOTE: in the case of sub-channel, we clear the sub-channel + * related bit(s) in primary->alloced_cpus_in_node in + * hv_process_channel_removal(), so when we reload drivers + * like hv_netvsc in SMP guest, here we're able to re-allocate + * bit from primary->alloced_cpus_in_node. + */ if (!cpumask_test_cpu(cur_cpu, &primary->alloced_cpus_in_node)) { cpumask_set_cpu(cur_cpu,