CFT: Realtek network driver update

Daniel Bilik ddb at
Fri Feb 24 01:34:50 PST 2017

On Fri, 24 Feb 2017 09:43:31 +0800
Sepherosa Ziehau <sepherosa at> wrote:

>> Second problem is more tough (or weird, I'd say), and AFAICT is
>> related to txcsum. New re(4) with txcsum turned on (which is default)
>> seems to create, under some circumstances, malformed UDP packets.
> Can you try this patch?
> It's a quick test.

Quick test has succeeded. :) The patch that disables m_devpad() call
has solved the issue: openvpn connection is initiated even with txcsum
enabled, and I don't see any side effects or network misbehaviour. Thank
you very much. :-)

>  BTW, can you give me the dmesg output related to
> re(4)?

Sure, dmesg(8) and pciconf(8) outputs are attached.

>  Tcpdump output would be helpful, if the patch did not fix your
> issue.

Though the patch did fix it, I have dumps for both "good" and "bad" UDP
packets. I'll send them to you privately, just FYI.

Thank you once again.

-------------- next part --------------
re0: <RealTek 8111/8168 PCIe Gigabit Ethernet> port 0xe000-0xe0ff mem 0xd0600000-0xd0603fff,0xd0604000-0xd0604fff irq 18 at device 0.0 on pci3
re0: MAC version 0x4c000000, MACFG 56, support MSI
re0: bus speed 125MHz
re0: MAC address: d0:50:99:4f:bc:50
-------------- next part --------------
re0 at pci0:3:0:0:	class=0x020000 card=0x81681849 chip=0x816810ec rev=0x11 hdr=0x00
    vendor     = 'Realtek Semiconductor Co., Ltd.'
    device     = 'RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller'
    class      = network
    subclass   = ethernet

More information about the Users mailing list