From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753321AbcEML4t (ORCPT ); Fri, 13 May 2016 07:56:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57326 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753124AbcEMLzh (ORCPT ); Fri, 13 May 2016 07:55:37 -0400 From: Vitaly Kuznetsov To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, devel@linuxdriverproject.org, Haiyang Zhang , "K. Y. Srinivasan" , "Lino Sanfilippo" Subject: [PATCH net-next v2 5/6] hv_netvsc: synchronize netvsc_change_mtu()/netvsc_set_channels() with netvsc_remove() Date: Fri, 13 May 2016 13:55:24 +0200 Message-Id: <1463140525-27338-6-git-send-email-vkuznets@redhat.com> In-Reply-To: <1463140525-27338-1-git-send-email-vkuznets@redhat.com> References: <1463140525-27338-1-git-send-email-vkuznets@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 13 May 2016 11:55:37 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When netvsc device is removed during mtu change or channels setup we get into troubles as both paths are trying to remove the device. Synchronize them with start_remove flag and rtnl lock. Signed-off-by: Vitaly Kuznetsov --- drivers/net/hyperv/netvsc_drv.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c index 7325d69..6a69b5c 100644 --- a/drivers/net/hyperv/netvsc_drv.c +++ b/drivers/net/hyperv/netvsc_drv.c @@ -759,7 +759,7 @@ static int netvsc_set_channels(struct net_device *net, int ret = 0; bool recovering = false; - if (!nvdev || nvdev->destroy) + if (net_device_ctx->start_remove || !nvdev || nvdev->destroy) return -ENODEV; num_chn = nvdev->num_chn; @@ -907,7 +907,7 @@ static int netvsc_change_mtu(struct net_device *ndev, int mtu) u32 num_chn; int ret = 0; - if (nvdev == NULL || nvdev->destroy) + if (ndevctx->start_remove || !nvdev || nvdev->destroy) return -ENODEV; if (nvdev->nvsp_version >= NVSP_PROTOCOL_VERSION_2) @@ -1445,7 +1445,12 @@ static int netvsc_remove(struct hv_device *dev) ndev_ctx = netdev_priv(net); net_device = ndev_ctx->nvdev; + /* Avoid racing with netvsc_change_mtu()/netvsc_set_channels() + * removing the device. + */ + rtnl_lock(); ndev_ctx->start_remove = true; + rtnl_unlock(); cancel_delayed_work_sync(&ndev_ctx->dwork); cancel_work_sync(&ndev_ctx->work); -- 2.5.5