From 90186af404ada5a47b875bf3c16d0b02bb023ea0 Mon Sep 17 00:00:00 2001 From: Peter Wu Date: Tue, 8 Dec 2015 12:17:42 +0100 Subject: [PATCH] r8152: fix lockup when runtime PM is enabled 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 Acked-by: Hayes Wang Signed-off-by: David S. Miller --- 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 d9427ca3dba7..2e32c41536ae 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); } -- 2.34.1