Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756237AbbLGQ66 (ORCPT ); Mon, 7 Dec 2015 11:58:58 -0500 Received: from lekensteyn.nl ([178.21.112.251]:51304 "EHLO lekensteyn.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753663AbbLGQ65 (ORCPT ); Mon, 7 Dec 2015 11:58:57 -0500 From: Peter Wu To: "David S . Miller" , hayeswang , linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Lu Baolu Subject: [PATCH] r8152: fix lockup when runtime PM is enabled Date: Mon, 7 Dec 2015 17:58:40 +0100 Message-Id: <1449507520-10671-1-git-send-email-peter@lekensteyn.nl> X-Mailer: git-send-email 2.6.3 X-Spam-Score: 0.0 (/) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2403 Lines: 69 When an interface is brought up which was previously suspended (via runtime PM), it would hang. This happens because napi_disable is called before napi_enable. Solve this by avoiding napi_disable before the device is fully up. While at it, remove WORK_ENABLE check from rtl8152_open (introduced with the original change) because it cannot happen: - After this patch, runtime resume will not set it during rtl8152_open. - When link is up, rtl8152_open is not called. - When link is down during system/auto suspend/resume, it is not set. Fixes: 41cec84cf285 ("r8152: don't enable napi before rx ready") Link: https://lkml.kernel.org/r/20151205105912.GA1766@al Signed-off-by: Peter Wu --- drivers/net/usb/r8152.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index d9427ca..b8b083e 100644 --- a/drivers/net/usb/r8152.c +++ b/drivers/net/usb/r8152.c @@ -3067,17 +3067,6 @@ static int rtl8152_open(struct net_device *netdev) mutex_lock(&tp->control); - /* The WORK_ENABLE may be set when autoresume occurs */ - if (test_bit(WORK_ENABLE, &tp->flags)) { - clear_bit(WORK_ENABLE, &tp->flags); - usb_kill_urb(tp->intr_urb); - cancel_delayed_work_sync(&tp->schedule); - - /* disable the tx/rx, if the workqueue has enabled them. */ - if (netif_carrier_ok(netdev)) - tp->rtl_ops.disable(tp); - } - tp->rtl_ops.up(tp); rtl8152_set_speed(tp, AUTONEG_ENABLE, @@ -3516,11 +3505,13 @@ static int rtl8152_resume(struct usb_interface *intf) if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) { rtl_runtime_suspend_enable(tp, false); clear_bit(SELECTIVE_SUSPEND, &tp->flags); - napi_disable(&tp->napi); - set_bit(WORK_ENABLE, &tp->flags); - if (netif_carrier_ok(tp->netdev)) - rtl_start_rx(tp); - napi_enable(&tp->napi); + if (tp->netdev->flags & IFF_UP) { + napi_disable(&tp->napi); + set_bit(WORK_ENABLE, &tp->flags); + if (netif_carrier_ok(tp->netdev)) + rtl_start_rx(tp); + napi_enable(&tp->napi); + } } else { tp->rtl_ops.up(tp); rtl8152_set_speed(tp, AUTONEG_ENABLE, -- 2.6.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/