>Number:         29596
>Category:       kern
>Synopsis:       wm0: wm_tx_offload: packet headers did not fit in first mbuf, packet dropped
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 04 14:39:00 +0000 2005
>Originator:     YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
>Release:        NetBSD 2.99.14
>Organization:

>Environment:
	
	
System: NetBSD kaeru 2.99.14 NetBSD 2.99.14 (build.kaeru) #218: Fri Mar 4 16:42:09 JST 2005 takashi@kaeru:/home/takashi/work/kernel/build.kaeru i386
Architecture: i386
Machine: i386
>Description:
	after i recently replaced an fxp(4) card with a wm(4) card
	on my nat box (and did s/fxp0/wm0/g in some config files,)
	most (if not all) of nat'ed packets start being discarded with
	the following message.

wm0: wm_tx_offload: packet headers did not fit in first mbuf, packet dropped

>How-To-Repeat:
	"ifconfig wm0 ip4csum" and use pf?

	ext_if="wm0"
	table <natinside> const { 10/8, 192.168/16 }
	nat on $ext_if from <natinside> to any -> ($ext_if)
>Fix:
	workaround: ifconfig wm0 -ip4csum

>Unformatted: