[Bug 205050] VLAN_MTU required by smsc driver

[bugzilla-noreply at freebsd.org]

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=205050

            Bug ID: 205050
           Summary: VLAN_MTU required by smsc driver
           Product: Base System
           Version: 11.0-CURRENT
          Hardware: arm
                OS: Any
            Status: New
          Severity: Affects Only Me
          Priority: ---
         Component: kern
          Assignee: freebsd-bugs at FreeBSD.org
          Reporter: rpp at ci.com.au

Created attachment 163881
  --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=163881&action=edit
patch to sys/dev/usb/net/if_smsc.c

When setting up VLANs on a Raspberry Pi ethernet port, the MTU drops from 1500
to 1496 bytes. The MTU should remain at 1500, extending the frame size as per
IEEE 802.3.  Adding IFCAP_VLAN_MTU to the if_capabilities field in the smsc
driver solves the problem.  The datasheet for the LAN9512 chip, section 3.2.3
states that the chip supports the extended frame.  Trivial patch attached.

-- 
You are receiving this mail because:
You are the assignee for the bug.