From de658a195ee23ca6aaffe197d1d2ea040beea0a2 Mon Sep 17 00:00:00 2001 From: Grant Grundler Date: Tue, 19 Jan 2021 17:12:08 -0800 Subject: net: usb: cdc_ncm: don't spew notifications RTL8156 sends notifications about every 32ms. Only display/log notifications when something changes. This issue has been reported by others: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1832472 https://lkml.org/lkml/2020/8/27/1083 ... [785962.779840] usb 1-1: new high-speed USB device number 5 using xhci_hcd [785962.929944] usb 1-1: New USB device found, idVendor=0bda, idProduct=8156, bcdDevice=30.00 [785962.929949] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=6 [785962.929952] usb 1-1: Product: USB 10/100/1G/2.5G LAN [785962.929954] usb 1-1: Manufacturer: Realtek [785962.929956] usb 1-1: SerialNumber: 000000001 [785962.991755] usbcore: registered new interface driver cdc_ether [785963.017068] cdc_ncm 1-1:2.0: MAC-Address: 00:24:27:88:08:15 [785963.017072] cdc_ncm 1-1:2.0: setting rx_max = 16384 [785963.017169] cdc_ncm 1-1:2.0: setting tx_max = 16384 [785963.017682] cdc_ncm 1-1:2.0 usb0: register 'cdc_ncm' at usb-0000:00:14.0-1, CDC NCM, 00:24:27:88:08:15 [785963.019211] usbcore: registered new interface driver cdc_ncm [785963.023856] usbcore: registered new interface driver cdc_wdm [785963.025461] usbcore: registered new interface driver cdc_mbim [785963.038824] cdc_ncm 1-1:2.0 enx002427880815: renamed from usb0 [785963.089586] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected [785963.121673] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected [785963.153682] cdc_ncm 1-1:2.0 enx002427880815: network connection: disconnected ... This is about 2KB per second and will overwrite all contents of a 1MB dmesg buffer in under 10 minutes rendering them useless for debugging many kernel problems. This is also an extra 180 MB/day in /var/logs (or 1GB per week) rendering the majority of those logs useless too. When the link is up (expected state), spew amount is >2x higher: ... [786139.600992] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected [786139.632997] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink [786139.665097] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected [786139.697100] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink [786139.729094] cdc_ncm 2-1:2.0 enx002427880815: network connection: connected [786139.761108] cdc_ncm 2-1:2.0 enx002427880815: 2500 mbit/s downlink 2500 mbit/s uplink ... Chrome OS cannot support RTL8156 until this is fixed. Signed-off-by: Grant Grundler Reviewed-by: Hayes Wang Link: https://lore.kernel.org/r/20210120011208.3768105-1-grundler@chromium.org Signed-off-by: Jakub Kicinski --- include/linux/usb/usbnet.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include') diff --git a/include/linux/usb/usbnet.h b/include/linux/usb/usbnet.h index 88a7673894d5..cfbfd6fe01df 100644 --- a/include/linux/usb/usbnet.h +++ b/include/linux/usb/usbnet.h @@ -81,6 +81,8 @@ struct usbnet { # define EVENT_LINK_CHANGE 11 # define EVENT_SET_RX_MODE 12 # define EVENT_NO_IP_ALIGN 13 + u32 rx_speed; /* in bps - NOT Mbps */ + u32 tx_speed; /* in bps - NOT Mbps */ }; static inline struct usb_driver *driver_of(struct usb_interface *intf) -- cgit v1.2.3