Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756089AbbLHLSA (ORCPT ); Tue, 8 Dec 2015 06:18:00 -0500 Received: from lekensteyn.nl ([178.21.112.251]:39050 "EHLO lekensteyn.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754562AbbLHLR6 (ORCPT ); Tue, 8 Dec 2015 06:17:58 -0500 From: Peter Wu To: Hayes Wang , "David S . Miller" , linux-usb@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Lu Baolu Subject: [PATCH v2] r8152: fix lockup when runtime PM is enabled Date: Tue, 8 Dec 2015 12:17:42 +0100 Message-Id: <1449573462-28417-1-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: 3162 Lines: 90 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_enable in the resume during open function (netif_running is true when open is called, IFF_UP is set after a successful open; netif_running is false when close is called, but IFF_UP is then still set). 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 --- v2: moved rtl_runtime_suspend_enable from close to rtl8152_suspend Tested with the scenario from https://lkml.kernel.org/r/20151208111008.GA18728@al (added debug prints to verify the suspend/resume moments) --- drivers/net/usb/r8152.c | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-) diff --git a/drivers/net/usb/r8152.c b/drivers/net/usb/r8152.c index d9427ca..2e32c41 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, @@ -3124,12 +3113,6 @@ static int rtl8152_close(struct net_device *netdev) } else { mutex_lock(&tp->control); - /* The autosuspend may have been enabled and wouldn't - * be disable when autoresume occurs, because the - * netif_running() would be false. - */ - rtl_runtime_suspend_enable(tp, false); - tp->rtl_ops.down(tp); mutex_unlock(&tp->control); @@ -3512,7 +3495,7 @@ static int rtl8152_resume(struct usb_interface *intf) netif_device_attach(tp->netdev); } - if (netif_running(tp->netdev)) { + if (netif_running(tp->netdev) && tp->netdev->flags & IFF_UP) { if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) { rtl_runtime_suspend_enable(tp, false); clear_bit(SELECTIVE_SUSPEND, &tp->flags); @@ -3532,6 +3515,8 @@ static int rtl8152_resume(struct usb_interface *intf) } usb_submit_urb(tp->intr_urb, GFP_KERNEL); } else if (test_bit(SELECTIVE_SUSPEND, &tp->flags)) { + if (tp->netdev->flags & IFF_UP) + rtl_runtime_suspend_enable(tp, false); clear_bit(SELECTIVE_SUSPEND, &tp->flags); } -- 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/