From 5de96355d7d7ebd8d4ee396392bfba93367eb9dd Mon Sep 17 00:00:00 2001 From: Kai-Heng Feng Date: Tue, 22 Sep 2020 10:15:44 +0800 Subject: [PATCH] igb: Report speed and duplex as unknown when device is runtime suspended stable inclusion from linux-4.19.129 commit 9fb0eb3d31c06d8dd550f0452979c3c3e9787759 -------------------------------- commit 165ae7a8feb53dc47fb041357e4b253bfc927cf9 upstream. igb device gets runtime suspended when there's no link partner. We can't get correct speed under that state: $ cat /sys/class/net/enp3s0/speed 1000 In addition to that, an error can also be spotted in dmesg: [ 385.991957] igb 0000:03:00.0 enp3s0: PCIe link lost Since device can only be runtime suspended when there's no link partner, we can skip reading register and let the following logic set speed and duplex with correct status. The more generic approach will be wrap get_link_ksettings() with begin() and complete() callbacks. However, for this particular issue, begin() calls igb_runtime_resume() , which tries to rtnl_lock() while the lock is already hold by upper ethtool layer. So let's take this approach until the igb_runtime_resume() no longer needs to hold rtnl_lock. CC: stable Suggested-by: Alexander Duyck Signed-off-by: Kai-Heng Feng Tested-by: Aaron Brown Signed-off-by: Jeff Kirsher Signed-off-by: Greg Kroah-Hartman Signed-off-by: Yang Yingliang Signed-off-by: Li Aichun Reviewed-by: guodeqing Signed-off-by: Yang Yingliang --- drivers/net/ethernet/intel/igb/igb_ethtool.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c index 50954e444985..2e17625e6c35 100644 --- a/drivers/net/ethernet/intel/igb/igb_ethtool.c +++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c @@ -143,7 +143,8 @@ static int igb_get_link_ksettings(struct net_device *netdev, u32 speed; u32 supported, advertising; - status = rd32(E1000_STATUS); + status = pm_runtime_suspended(&adapter->pdev->dev) ? + 0 : rd32(E1000_STATUS); if (hw->phy.media_type == e1000_media_type_copper) { supported = (SUPPORTED_10baseT_Half | -- GitLab